HomeMy WebLinkAboutStaff Report 8586
City of Palo Alto (ID # 8586)
City Council Staff Report
Report Type: Consent Calendar Meeting Date: 11/13/2017
City of Palo Alto Page 1
Summary Title: Vulnerable Buildings Seismic Risk Assessment Study
Title: Direct Staff to Return to Policy and Services Committee With
Amendments to the Municipal Code for the Regulation of Seismic Vulnerable
Buildings (Continued From October 16, 2017)
From: City Manager
Lead Department: Development Services Department
Recommendation
Unless council directs otherwise, staff intends to take the existing research and findings on
seismically vulnerable buildings completed to date (explained in this report and attachments)
and start the process of drafting updates to local regulations, policies, and procedures including
an analysis of any potential CEQA requirements. Staff will be returning to Council for request to
enter into a new contract(s) for technical services and then work with the Policy and Services
Committee and ultimately the City Council to review revised language, options, and
implications associated with modifications to seismic compliance in our municipal code.
Background
This work was completed per direction given by the City Council in 2014, in response to the
Napa Valley earthquake. Staff has been working in collaboration with a multi-stakeholder group
made up of other city departments and external interest groups along with support from a
technical consultant to review our exposure to seismic hazards. We have developed the
following findings.
In 1986, the City Council adopted the Seismic Hazards and Identification Program, codified in
the Palo Alto Municipal Code, to establish a mandatory evaluation and reporting program
including incentives for property owners to voluntarily upgrade their structurally deficient
buildings. Three categories of buildings are addressed in that ordinance:
1. Category I Buildings: Buildings constructed of unreinforced masonry (URM), except for
those smaller than 1,900 square feet with six or fewer occupants. These buildings are
located in the Downtown Commercial area.
2. Category II Buildings: Buildings constructed prior to January 1, 1935, containing one
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hundred (100) or more occupants.
3. Category III Buildings: Buildings constructed prior to August 1, 1976, containing three
hundred (300) or more occupants.
On September 15, 2014, several weeks after August 24, 2014 Napa Valley earthquake, the City
Council received an update from the Office of Emergency Services regarding the Threats and
Hazard Identification Risk Assessment report. During the study session, City Council suggested
that the Policy and Services Committee:
1. Identify and prioritize buildings that pose potential risks in earthquakes, including soft story
buildings and other types of construction.
2. Review and summarize best practices from other government agencies regarding
prioritization of various seismically vulnerable buildings, including retrofit incentives and
requirements.
3. Review current or pending State legislation related to soft-story buildings and other
structurally deficient buildings.
On December 9, 2014 the Council’s Policy and Services Committee recommended the City
Council authorize a Request for Proposal to prepare an update to the City’s Seismic Hazards
Identification Program and update the inventory of structurally deficient buildings in the multi-
family, commercial and industrial areas of the city, categorizing building typologies to include:
1. URM, 2. Soft-Story, 3. Tilt-Up Construction, 4. Non-ductile Concrete, and 5. Steel Moment
Frame.
On August 17, 2015, City Council approved a contract with Rutherford + Chekene to complete a
study and provide recommendations for improvement of City’s Seismic Program. On April 17,
2017, staff advanced a comprehensive information report to City Council including the results
of the Rutherford + Chekene report.
Discussion
The April 17, 2017 staff report (attached) is a thorough analysis including a 34 page staff
summary of the Rutherford + Chekene’s 110 page report. The Rutherford + Chekene report is
also attached however any non-pertinent appendixes have been removed to save paper. All
documents related to the study and previous staff reports are located on the City’s website:
http://www.cityofpaloalto.org/gov/depts/ds/srmag.asp.
In addition to the support from our consultant, staff convened a Seismic Risk Management
Advisory Group (SRMAG). The group consisted of residents, experienced contractors, property
owners and local advocates. Six meetings were held, led by the Rutherford + Chekene and
included staff from Building, Planning, Fire, Office of Emergency Services, and Public Works.
The intent of the SRMAG process was not to gain consensus or ratify any particuarly policy
proposal, but rather to gauge community interest, clarify alternative directions, and highlight
City of Palo Alto Page 3
key issues that need to be addressed moving forward.
The SRMAG expressed little to no support for leaving the status quo program unchanged.
Strong support did exist for: 1. Taking action to resolve buildings (through retrofit or
demolition) already in the program, particularly URM buildings, 2. Addressing more building
types, particularly soft story wood-frame, and 3. Utilizing a variety of disclosure measures and
potentially some incentives. All presentations and minutes from the meetings are also available
on the aforementioned website. Attachment A summarizes policy options that came out of the
Seismic Risk Assessment, as presented to staff and discussed by the SRMAG.
Staff intends to take action on recommendations provided to the Council on provided on April
17, 2017 in Staff Report 7095.
Program Options:
1. Status quo;
2. Increase number of building types regulated, but retrofit remains voluntary;
3. Increase number of building types regulated with additional disclosure measures
incorporated;
4. Increase number of building types regulated, some building types have voluntary retrofit
and a few building types have mandatory retrofit, with enforcement by a trigger threshold
when the building is sold or undergoes substantial renovation;
5. Increase number of building types regulated, retrofits for some categories are voluntary and
a few categories are mandatory, with enforcement by a fixed timeline;
6. Increase number of building types regulated, but more categories are required to have
mandatory retrofits.
Building Types:
In an effort to more accurately capture the diverse range of existing building types the study
suggested staff consider the expansion of the existing building types to include four additional
types. Attachment A is a summary table indicating the category, approximate number of
buildings in each category, the building type, date of construction, occupant levels, threshold
elements, deadlines and potential incentives.
1. Existing: Category I Buildings: Buildings constructed of unreinforced masonry (except for
those smaller than 1,900 square feet with six (6) or fewer occupants). These buildings are
located in the Downtown Commercial area.
2. Existing: Category II Buildings: Buildings constructed prior to January 1, 1935, containing
one hundred (100) or more occupants.
3. Existing: Category III Buildings: Buildings constructed prior to August 1, 1976, containing
three hundred (300) or more occupants.
4. Proposed: Category IV Buildings: Buildings constructed of soft-story wood frame, prior to
1977.
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5. Proposed: Category V Buildings: Building constructed of tilt-up, prior to 1998.
6. Proposed: Category VI Buildings: Building constructed of soft-story concrete, prior to 1977.
7. Proposed: Category VII Buildings: Buildings constructed of steel moment frame, prior to
1998.
Types of Disclosure Measures
Another outcome of the study and stakeholder engagement resulted in the identification of
potential ways to disclose the seismic vulnerability of a building. Attachment B is a table
describing the disclosures listed below with their description, examples of use, advantages, and
disadvantages. Given that staff has to further define and verify the current inventory of
vulnerable buildings and assess community, business and economic implications, having all
measures available will be helpful.
1. Mandatory disclosure at the time of sale
2. Recorded notice on deed
3. Public listing of affected properties
4. External signage
5. Tenant notification
6. Earthquake performance rating system
Types of Incentives
The study conducted by the team of staff, stakeholders and technical consultant revealed a
range of incentives that could be used in seeking compliance with a proposed seismic retrofit
ordinance. Attachment C is a table describing the incentives listed below with their
description, examples of use, advantages, and disadvantages. Going forward staff intents to
explore the following incentives as we review options and draft an ordinance that will be
reviewed by the Policy and Services Committee and back to the City Council.
1. Expedited Planning Entitlement
2. Density or Intensity Bonuses, such as Floor-to-Area Ratio (FAR) bonuses
3. Exemptions for Non-Conformities
4. Zoning Incentives
5. Condominium Conversion Assistance
6. Exemption from Future Retrofit Requirements
7. Transfer of Development Rights (TDR’s)
8. Permission to add units (such as in soft-story wood frame apartment construction)
9. Expedited Building Permitting
10. Technical Assistance
Summary of Seismic Risk Assessment Study Key Findings
Due the volume and depth of information provided in the April 17, 2017 staff report as well as
the Seismic Risk Assessment Study, staff and our consultant have prepared the following key
findings. For a more detailed understanding of these findings staff recommends the City Council
City of Palo Alto Page 5
and community read the April 17, 2017 staff report and the Seismic Risk Assessment Study.
1. Thirty years later, Palo Alto’s existing mandatory evaluation, voluntary retrofit program has
been largely successful at addressing buildings with URM load-bearing walls.
2. The modest scope of the existing program and lessons learned from seismic events since
the program was adopted, means that we now believe there are vulnerable building types
that have not been addressed. Five additional categories were identified from the Risk
Assessment Study as meeting the criteria of being potentially hazardous and having a
meaningful presence in Palo Alto. The decision whether to include some or all of these five
categories in an expanded seismic retrofit program is an important policy decision. Based
on an initial review, there are approximately 635 buildings located throughout the City,
both residential and commercial uses, that may fall into these categories.
3. If no action is taken, losses in these buildings from a large nearby seismic event may be
significant, on the order of $2 billion. That estimate does not include lives lost, economic
disruption, loss of housing, emergency services costs, displacement or other effects.
4. Estimated losses could be reduced by up to one third to one half if all the identified
vulnerable structures were retrofitted. For all five additional categories recommended for
consideration, analysis of protype retrofitting strategies showed high likelihood of being
cost-effective. In other words, losses avoided will exceed retrofit costs, in some categories
by fourfold or more. This does not suggest that all of the retrofits would necessarily be
financially feasible for current building owners, particularly in the absence of incentives
and/or favorable financing terms.
5. Over the past ten years, an increasing number of California cities have expanded their
seismic mitigation programs to address one or more of the five additional vulnerable
building types identified in the Risk Assessment. In particular, five Bay Area cities (San
Leandro, Fremont, Berkeley, Oakland and San Francisco) have well-established mandatory
retrofit programs for soft-story wood frame buildings, which are typically multi-family
residential or mixed use. Cities with newer programs include Los Angeles and West
Hollywood. Several cities have also implemented or are actively considering ordinances for
tilt-up and older concrete structures.
6. Most programs package together a variety of policy features and timelines that differ by
building type(s) and priority tiers. Education, notification and appeal, evaluation, permit
application and retrofit deadlines are implemented in phases during an overall timeframe
ranging from two to 25 years. A variety of incentives can also be offered for some or all
affected owners, but in fact, very few cities offer any kind of significant financial assistance
beyond fee waivers.
Resource Impact
Implementation of future City Council action and development of an expanded Seismic Hazards
and Identification program and ordinance would result in additional costs to private property
owners. Attachment D is a table of financing tools provide by Rutherford + Chekene. Staff is not
seeking Council input at this stage. Upon returning to Policy and Services Committee, staff will
provide recommendations for possible financing strategies.
City of Palo Alto Page 6
Staff time from Development Services, Planning and Community Environment, Fire, Office of
Emergency Services, and Public Works departments will continue to be needed. Additionally,
consulting services to further define and verify the current inventory of vulnerable buildings;
assess community, business and economic implications; and to determine scope of updates to
local regulations, policies and procedures will be required. Staff will return to the Council for
authorization to enter into a new contract(s) for technical services including potentially CEQA
compliance and will work with the Policy and Services Committee to review options,
implications and ultimately draft a new ordinance that will come before the City Council for
approval.
Environmental Review
No environment review is necessary under California Environmental Quality Act (CEQA) at this
time, as staff is continuing to collect information for City Council action. Staff will conduct the
appropriate level of environmental assessment may be required prior to adoption of updates to
the City’s Seismic program.
Attachments:
Attachment A - Program Options and Building Types
Attachment B - Types of Disclosure Approaches
Attachment C - Types of Policy Incentives
Attachment D - Types of Financial Tools
Attachment E - 4-17-17 Staff Report
Attachment F - Seismic Risk Assessment Study by Rutherford + Chekene
Palo Alto Seismic Risk Assessment Study December 21, 2016
Final Report Page 4
Summary of Recommended Policy Directions from the Seismic Risk Management Program Advisory Group
Category Approx.
Number
Building
Type
Date of
Construction
Occupants Evaluation
Report
Voluntary,
Triggered, or
Mandatory
Retrofit1
Deadlines for Evaluation Report and
Retrofit Construction (years)2
Disclosure Potential Incentives
Current Program (Potential Revision in Italics)
I 10 Un-
reinforced
masonry
NA Over 6
(and over
1,900 sf)
Required Mandatory Report: Expired
Construction: 2-4
Website
listing and
tenant
notification
Fee waiver, expedited
permitting, FAR bonus/
transfer of development
rights (TDR) II 4 Any Before 1/1/35 Over 100 Required Voluntary or
Triggered
Report: Expired
Construction
• Voluntary: Not required
• Triggered: At sale or renovation
III 9 Any Before 8/1/76 Over 300 Required Voluntary or
Triggered
Expanded Program
IV 294 Soft-story
wood
frame
Before 1977 Any Required Triggered or
Mandatory
Report: 2-4
Construction
• Triggered: At sale or renovation
• Mandatory: 4-6
Same as
above
Fee waiver, expedited
permitting, TDR, parking
exemptions, permission to
add units
V 99 Tilt-up Before 1998 Any Required Triggered or
Mandatory
Report: 2-4
Construction
• Triggered: At sale or renovation
• Mandatory: 4-6
Same as
above
Same as Categories I, II and
III
VI 37 Soft-story
concrete
Before 1977 Any Required Voluntary,
Triggered or
Mandatory
Report: 2-4
Construction
• Voluntary: Not required
• Triggered: At sale or renovation
• Mandatory: 6-8
Same as
above
Same as Categories I, II and
III
VII 35 Steel
moment
frame
Before 1998 Any Required Voluntary,
Triggered or
Mandatory
VIII TBD Other older
nonductile
concrete
Before 1977 Any Not rec. at
this time
Not
recommended
at this time
Report: NA
Construction: NA
NA NA
1Voluntary: Retrofit is voluntary.
Triggered: Retrofit is triggered when the building is sold or undergoes substantial renovation.
Mandatory: Retrofit is required per a fixed timeline.
2Deadlines provide a potential range. Timelines would vary depending on tiers or priority groupings of different subcategories.
Attachment A
Seismic Risk Assessment Study December 21, 2016
Final Report Page 56
Table 4: Description of disclosure approaches used in local earthquake risk reduction programs.
Name Description Examples of Use Advantages Costs, Issues or Concerns
Mandatory Disclosure
at Time of Sale
Sellers of property are required
to disclose features that could
relate to earthquake
performance.
California Earthquake
Fault Zone disclosure;
Sellers of pre-1960
homes are required to
fill out to the best of
their knowledge and
provide buyers with
Residential
Earthquake Hazards
Report.
Empowers buyers to be
aware of any known
existing hazard issues.
Anecdotally, many buyers do
not pay enough attention to
these disclosures, which occur
during emotional, busy
decisionmaking periods. They
may not seek expert
information to interpret the
reported information. It is also
possible that sellers shirk on
the disclosure requirements if
buyers do not know that they
are supposed to receive them.
Difficult to enforce.
Recorded Notice on
Deed
Jurisdictions can record on the
property title or deed the fact
that the building is subject to
additional requirements
related to its earthquake
vulnerable status.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Relatively low cost for
jurisdictions to implement.
Empowers buyers but also
mortgage companies to be
aware of any known
existing hazard issues.
Anecdotally, it is not clear how
many buyers or mortgage
companies pay attention to
these notices. Such notices are
primarily effective only at time
of sale or refinance.
Attachment B
Table 4 (continued)
Seismic Risk Assessment Study December 21, 2016
Final Report Page 57
Name Description Examples of Use Advantages Costs, Issues or Concerns
Public Listing of
Affected Properties
Jurisdictions that operate web
sites to describe their
programs can feature a full list
of property addresses,
potentially also including also
the compliance status of the
property. In general, owner
names are not listed, though
that information is available if
a member of the public
searched for it separately.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Relatively low cost for
jurisdictions to implement.
Could be used by tenants
and buyers when
searching for properties,
thus empowering well-
informed market
negotiations over pricing.
Website information needs to
be updated on a regular basis
in order to be perceived as fair
and useful. Public lists work
better if the property
addresses are searchable,
rather than static (e.g., on a
pdf).
External Signage Jurisdictions that operate web
sites to describe their
programs can feature a full list
of property addresses,
potentially also including the
compliance status of the
property. Some lists are
searchable, while others are
static.
California state
requires a sign on all
URM buildings. Similar
signage has been
required since 2007
on soft-story wood
frame buildings in the
City of Berkeley.
Advocates argue that signs
are justified based on the
public's right to know. The
physical presence and
repeated viewing of
signage may make the
issue more salient for
visitors, employees, lease
holders, and owners alike.
Owners may view the signs as
stigmatizing or threatening to
property value or business
revenues, but anecdotally, it is
not clear how much visitors,
employees, residents, and
other users of a building pay
attention to signage when
entering or leaving a property.
Attachment B
Table 4 (continued)
Seismic Risk Assessment Study December 21, 2016
Final Report Page 58
Name Description Examples of Use Advantages Costs, Issues or Concerns
Tenant Notification Owners are required to present
straightforward, standardized
information about the listed
status of the property. Some
jurisdictions require proof of
notification (e.g., tenant
signature) to be returned and
kept on file with the city.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Tenant notification may be
more influential than
signage because it is
personalized and the
information is delivered at
a useful time in that
person's decision process.
Advocates claim that
tenant notification is
justified based on the
public's right to know.
To be effective, tenant
notification should be required
to occur well before the
potential tenant is ready to
sign the lease.
Earthquake
Performance Rating
Systems
Owners can be either
encouraged or required to
have their building rated on a
standardized scale that
classifies expected building
performance in an earthquake
in an easier to understand
format, for instance from one
to five stars. Viable rating
systems exist for many building
types.
The City of Los
Angeles in 2015
officially launched a
voluntary effort to
encourage owners to
rate their properties
using the US
Resiliency Council
system and pledged to
rate its own public
buildings as well.
Rating system use is
common for institutions
like universities and
hospitals. Mechanisms for
implementing
performance ratings for
commercial use have
recently matured and are
now viable. Ratings have
the potential to inform
owner, renter and buyer
decisions, creating a
market effect.
Obtaining a rating potentially
adds cost to a design project.
Ratings systems such as USRC’s
are relatively new and not yet
widely implemented.
Attachment B
Policy Incentives Used in Local Earthquake Risk Reduction Programs.
Type of Incentive Description Examples of Use Advantages Costs, Issues or Concerns
Density or Intensity
Bonuses
Specific increases in the
maximum allowable
building density or
intensity to help offset
the added costs of
seismic upgrades.
Palo Alto’s Floor Area Ratio
bonus program.
Owners that invest in a retrofit
can expand their projects in
order to increase future
revenue.
Typically,feasible only in areas
of high growth. Sometimes
controversial because of
potential community impacts
such as increased traffic, parking
needs, and rental rates.
Exemptions for Non‐
Conformities
Relief from timelines or
waivers of required work
such as fire resistance
upgrades and sprinklers,
Title 24 energy analysis
and upgrades, parking,
setback or other current
code measures that
would otherwise be
triggered by the size of
the project being
undertaken for projects
involving qualifying
retrofit work.
None identified.Offering relief from what may
be expensive rehabilitation of
nonconforming uses can make
seismic retrofits easier to design
and more affordable.
May be viewed as an excessive
concession to owners among
some members of the public.
Attachment C
Type of Incentive Description Examples of Use Advantages Costs, Issues or Concerns
Zoning Incentives Specific concessions
regarding encroachment
into setbacks, increased
allowable floor/area
ratios (FAR), height
limits, or onsite parking
requirements to help
offset the added costs of
seismic upgrades.
Since 1986, Palo Alto
allowed owners of included
buildings in the downtown
area to expand the floor
area if the owner
performed seismic
upgrades. Buildings were
also exempted from onsite
parking requirements and
fees for offsite parking.
Useful when bond financing
options are prohibitively costly
or not much more attractive
than private credit terms. Most
likely to work when zoning plans
in the community generally call
for limited to no growth. Costs
to the city are mainly in the
form of technical and design
cost review of proposed
projects.
Similarly‐situated properties
must be treated alike so as to
avoid claims of "spot zoning."
Citizens may object to special
treatment for work that could
be seen as essential anyhow.
Not likely to work in locations
with little development pressure
or where the community favors
growth.
Condominium
Conversion Assistance
Process expediting for
condo conversion for
properties that
seismically retrofit.
None identified.In jurisdictions where condo
conversation rates are capped
or allocated by lottery, offering
priority to buildings that retrofit
could be an effective tool to
promote seismic upgrading of
multifamily buildings.
May negatively impact other
housing affordability goals. Only
available to owners that can
afford it, unless accompanied by
other assistance programs.
Exemption from Future
Retrofit Requirements
Relief from imposition of
future retrofit
requirements for a
certain period following
completion of qualifying
seismic work.
The City of Berkeley offered
a 15‐year exemption from
future retrofit requirements
for soft‐story wood frame
properties that did a retrofit
concurrent with its
mandatory evaluation
program.
This can motivate owners to
complete retrofit work sooner
rather than later in order to
reduce uncertainty about future
city policies, and allows owners
to better anticipate business
expenses over a longer term.
The jurisdiction could not easily
impose new regulation on
exempted properties, even if
such policies became warranted
by new technologies or
knowledge.
Attachment C
Type of Incentive Description Examples of Use Advantages Costs, Issues or Concerns
Transfer of Development
Rights (TDR)
TDR allow owners to
transfer unused
development rights that
are comparable to the
value of the retrofit to
another site.
Very commonly used for
historic preservation,
including in Palo Alto.
Useful when the use of the
building in question is not likely
to generate added value to
justify the costs of the retrofit
work. This is most useful when
retrofit costs can be particularly
high and there are natural or
regulatory use restrictions.
Careful analysis of construction
costs is necessary to avoid
situations of under‐ or over‐
compensation.
Expedited Permits,
Inspections, and Reviews
Prioritization,
expediting, or bypassing
of certain internal
protocols for over the
counter permits and
inspection processes for
projects involving
seismic retrofit work.
Several Bay Area cities have
anecdotally stated that this
is their internal policy, but
no official records of such
were identified.
This can relieve the burden of
time and hassle for owners in
getting permits and inspections,
which are a significant source of
cost and uncertainty for owners
during retrofit projects.
Requires flexibility on the part of
city staff and plan check
consultants.
Technical Assistance Case‐management style
assistance for owners
and/or engineers during
the process of obtaining
financing, complying,
permitting, and carrying
out retrofit projects. This
is different than
engineering advice
about how to resolve
specific technical issues
of design.
Cities such as Berkeley have
found it necessary to
maintain additional staff to
operate their mitigation
programs. A significant
portion of their staff time is
devoted to owner and
engineer consultation.
Knowledgeable staff can help
owners navigate complex issues
such as investigating and
applying for incentives (if
offered), following guidelines, or
addressing the necessary
standards.
Labor costs to the city for
additional staff. Difficulty
sustaining project funding and
staff continuity over time.
Attachment C
Financial Tools Used in Local Earthquake Risk Reduction Programs.
Financial Tools Description Examples of Use Advantages Costs, Issues or Concerns
General Obligation or
Special District Bonds
Direct provision of funds
for qualifying retrofit
work based on voter
approval of issuance of
new municipal or state
debt to be repaid by
taxation.
This mechanism is
commonly used for seismic
improvements to
infrastructure, but also has
been used in URM building
programs and for retrofit of
historic properties. One
URM example is the city of
Long Beach, which offered
11.3% interest financing to
participating members of a
Special District created for
URM building owners.
Once passed, this type of
funding can be distributed over
time as provided for in the
approved wording.
Must be approved by two thirds
of voters, which sets a high bar
even if there is significant public
support. Jurisdictions must
administer the allocation of
funds and have at times not
been able to use all of it. Owner
education about the provisions
of the program is critical.
Owners of highly leveraged
buildings and buildings in
depressed areas may be unable
to meet prerequisite loan‐to‐
value ratio criteria. Retrofits are
generally not revenue‐
generating improvements upon
which financing can be
leveraged.
Grants Direct provision of funds
for qualifying retrofit
work.
CEA's Earthquake Brace &
Bolt program for single
family homes.
Some sources exist for city‐scale
projects or privately‐owned
buildings, such as FEMA Pre‐
Disaster Mitigation Grants.
Limited sources exist. Programs
can be difficult to manage
administratively. Fairness
concerns exist over which
owners can benefit.
Attachment D
Financial Tools Description Examples of Use Advantages Costs, Issues or Concerns
Property‐Assessed
Financing Loans
Also known as a
Property Assessed Clean
Energy (PACE) program,
this works as a loan to
an individual property
owner, transferrable to
future owners, where
the upfront costs of
qualifying work are
repaid over a period of
approximately 20 years
through the owner's
property tax
assessment.
San Francisco's PACE
program.
Provides an upfront way for
owners to access private capital
to afford retrofit projects. The
loan can be paid off over time
through higher rents or at future
sale, as well as being
transferrable to future owners.
Administratively complex for
both jurisdictions and owners.
Challenges include setting up
this complex financing
instrument which has heavy
involvement of third parties,
barriers to owners that want to
refinance, and barriers to the
transfer of a PACE‐financed
properties to a new owner.
Owners may not need it if
affordable regular market
capital is available. Lenders may
resist allowing an additional
lien.
Tax Credits Waiver of a portion of a
business, parcel, or
income tax for a number
of years to encourage
owners to retrofit.
Although vetoed by the
Governor, the legislature of
California passed AB 428 in
2015, which would have
offered up to 30% credit for
qualifying retrofit costs.
The funding source can be
outside the local jurisdiction,
and depending on the clarity of
program requirements, owners
can count on the funds as part
of planning their project.
Owners would need to be aware
of the credit and verify
qualifying work and complete all
follow up documentation.
Mostly benefits owners already
intending to retrofit and those
with more financial and business
sophistication.
Attachment D
Financial Tools Description Examples of Use Advantages Costs, Issues or Concerns
Real Estate Transfer Tax
Rebates
Building owners can
apply for a rebate of a
fraction (usually 1/3, up
to a cap) of the amount
of the transfer tax owed
to the city for a property
at sale for any qualifying
seismic improvement
expenditures made
within a certain period
before or after transfer
of title.
This policy has existed in
Berkeley since 1991 for
residential dwellings up to
four units and in San
Francisco since 2008 for
properties worth $5 million
or more.
In Berkeley, the program was
immediately popular and
eventually highly influential in
increasing support for other
earthquake policies because it
touched so many community
members and firmly established
a tone that the city takes seismic
risk seriously and will put its
“money where its mouth is.”
About half the single‐family
homes and one third of the
smaller rental buildings in
Berkeley have claimed the
credit, leading to widespread
community awareness of
seismic safety issues.
The jurisdiction forgoes tax
revenue. Anecdotally in
Berkeley, city officials had no
easy way to assess the quality of
work done. Some experts
suspect that some of the funds
went to incomplete or
improperly done retrofits.
Waivers or Reductions of
Building Department
Fees
Full waivers, fixed,or
percentage‐based
reductions of building
permit fee reductions.
The Jurisdictions of San
Francisco, Berkeley, and
Alameda have offered flat
or waived plan check fees
as an incentive for owners
to retrofit their buildings.
Oakland currently offers a
flat permit fee of $250 for
owners of qualified single‐
family residences to
perform seismic retrofits.
Modestly reduces the cost of a
retrofit project. Easy for city to
implement. Perceived by
owners as a significant gesture
of good will by owners, who
may feel it is "the least the city
could do."
This measure has direct loss of
revenue implications for the
jurisdiction.
Attachment D
Financial Tools Description Examples of Use Advantages Costs, Issues or Concerns
Pass Through of Retrofit
Costs to Tenants
For residential
properties in
jurisdictions with rent
control laws in place,
owners who seismically
retrofit their buildings
could be allowed to pass
through all or a fraction
the costs of these
retrofits to renters in
rent‐controlled units,
amortized over a
particular time period
such as 10 years.
Berkeley is 100% pass‐
through, San Francisco is
50%, and Oakland is %75.
Perceived as fair by owners
because tenants that benefit
most from the retrofit work pay
a share of it. Owners can use
this anticipated source of
revenue as a basis for securing a
loan.
Tenants with fixed or low
incomes might suffer hardship
with the added costs, although
hardship provisions can lessen
those effects.
Special District or
Historic Designation Tax
Reductions
Creation of Mello‐Roos,
Mills Act, historic or
other special districts
that are then eligible for
special loans, grants, or
tax credits.
For URM buildings, the
jurisdictions of St. Helena
and West Hollywood used
Mello‐Roos funding.
Provides a clear way for a local
jurisdiction to provide direct
funding or special financing
rates for privately‐owned
vulnerable properties.
Can be difficult for jurisdictions
to initiate and carry out. Owners
must join the special district at
the outset or will be left out of
future funding availability.
Attachment D
City of Palo Alto (ID # 7095)
City Council Staff Report
Report Type: Informational Report Meeting Date: 4/17/2017
City of Palo Alto Page 1
Summary Title: Palo Alto Seismic Risk Assessment Study Results
Title: Palo Alto Seismic Risk Assessment Study Results
From: City Manager
Lead Department: Development Services Department
RECOMMENDATION
This is an Informational Report, no City Council action is required at this time. Staff
recommends that the City Council review the Seismic Risk Assessment Study prepared by
Rutherford + Chekene, structural engineers. The study includes input from City of Palo Alto’s
Seismic Risk Management Advisory Group. Once Council is familiar with this study, staff will
prepare to return for a study session and direction.
EXECUTIVE SUMMARY
This informational item is intended to give the City Council advance background for an
upcoming study session related to a Seismic Risk Assessment Study of vulnerable building
construction in Palo Alto. In 2014, following the 6.0 magnitude earthquake in August 2014 in
the Napa Valley and the Office of Emergency Service’s Threats and Hazard Identification and
Risk Assessment Report, the Council directed staff to identify and prioritize buildings that pose
a potential seismic hazard in Palo Alto; review ‘best practices’ used by other communities for
addressing retrofit of seismically vulnerable buildings; and review current and pending State
legislation addressing these building types.
Rutherford + Chekene was selected to perform a comprehensive assessment of the expected
performance of the City’s building stock in potential earthquakes, including a community
engagement effort to help identify resiliency goals and associated mitigation policies and
programs. Specific details about the report can be found in this staff report and attached
consultant report. (Attachments B)
In this staff report, staff has summarized the outcome of the Seismic Risk Assessment and the
Advisory Group’s input on revisions to consider for the City’s Building and Zoning Ordinances.
Some of the study recommendations have significant policy and cost implications that will
require further study and Council review. All of these recommendations are discussed in this
staff report and in the detailed technical reports attached. (Attachments B and G)
Attachment E
City of Palo Alto Page 2
Next steps following council study session on this matter may include public outreach to
educate the community on vulnerable buildings. Staff, with the help of consultants, will review
potential incentives for retrofits and policies to minimize displacement of existing uses and
tenants. Staff would return to the Council with a recommendation to revise the current seismic
mitigation ordinance based on findings and community feedback. To be effective, there will
need to be a plan for staffing the program. Finally, during the study session staff will also
discuss potential policy implications such as displacement of existing building uses and tenants,
incentives for voluntary building retrofits, and the effects these benefits might have on
construction.
BACKGROUND
On September 15, 2014, the City Council directed staff to work with the Policy and Services
Committee to address the following:
A. Identification and prioritization of buildings that pose a potential hazard in an
earthquake, including soft-story buildings and other types of construction
B. Review of "best practices" from other cities regarding prioritization of various
seismically vulnerable buildings, including retrofit incentives and requirements
C. Review of current or pending State legislation related to soft-story buildings and other
structurally deficient buildings
Two events precipitated the Council’s direction: (1) the 6.0 magnitude earthquake on August
24, 2014, in Napa Valley and (2) the City Council’s review of the Office of Emergency Service’s
Threats and Hazard Identification and Risk Assessment report on September 15, 2014, which
identified over 130 seismically vulnerable buildings. (Attachment C)
<http://www.cityofpaloalto.org/civicax/filebank/documents/43866>
Current Code Provisions, Building Identification and Prioritization
In 1986, the City Council adopted the Seismic Hazards and Identification Program codified at
PAMC Section 16.42. (Attachment A) This ordinance established a mandatory evaluation
and reporting program and created incentives for property owners primarily in the
Downtown area to voluntarily upgrade their structurally deficient buildings. Three
categories of buildings were identified, including:
1. Category I Buildings: Buildings constructed of unreinforced masonry (except for those
smaller than 1,900 square feet with six (6) or fewer occupants). These buildings are
located in the Downtown Commercial area.
2. Category II Buildings: Buildings constructed prior to January 1, 1935, containing one
hundred (100) or more occupants.
3. Category III Buildings: Buildings constructed prior to August 1, 1976, containing three
hundred (300) or more occupants.
Attachment E
City of Palo Alto Page 3
The categories used in 1986 were developed by a citizens’ committee, reviewed by staff and
the Policy and Services Committee, and adopted by the City Council. These categories were
created to record known URM buildings and other potentially structurally deficient buildings
with relatively high numbers of occupants.
This program identified 89 buildings and was successful in two significant ways. One
hundred percent (100%) of the property owners complied with the ordinance and submitted
engineering reports detailing structural deficiencies and recommendations to strengthen
structures to alleviate the threat of collapse. Further, approximately seventy-four percent
(74%), or sixty-six buildings, were strengthened, demolished, or proposed to be demolished.
See (Attachment D) for current status of all inventoried properties.
Part of this success may be attributed to incentives that allowed upfront engineering report
costs be applied toward permit fees and the ability for property owners in the Downtown
Commercial (CD) district to add up to 2,500 square feet of new floor area, or twenty-five
percent (25%) of the existing building area, whichever is greater, to the site without having
to provide additional parking. This floor area bonus could be used onsite or transferred to
another owner or property in the Downtown Commercial district. Approximately twenty-
one (21) property owners took advantage of this incentive.
Despite its successes, twenty-three (23) buildings identified from that original inventory
remain vulnerable. Further, there are other building types in the City that were not
surveyed prior to adoption of the 1986 ordinance. For example, problems with soft story
wood-frame construction were documented following the 1994 Northridge Earthquake,
which resulted in changes to construction industry standards a few years later.
In 2003, the Collaborative for Disaster Mitigation at San Jose State University completed an
“Inventory of Soft-First Story Multi-Family Dwellings in Santa Clara County.” According to
the report, the City of Palo Alto had 130 soft story multi-family buildings including 1,263
residential units housing 3,158 occupants.
Other construction types of concern that were not surveyed in 1986 include non-ductile
concrete buildings, older steel moment frame buildings, and older concrete tilt-up buildings,
in addition to soft story wood-frame construction.
The City’s existing ordinance requires annual reporting to the City Council on the status of
the program. This reporting appears to have ended in 2004 for unknown reasons. More
recently, the City Council adopted an ordinance (Attachment E - update to ORD 5356)
modifying the seismic incentive so that parking must now be provided if an owner seeks to
add 2,500 square feet or 25% of the total building area in the CD District.
Policy and Services Recommendation and Council Authorization
On December 9, 2014, the Policy and Services Committee of the Palo Alto City Council
Attachment E
City of Palo Alto Page 4
recommended the City Council authorize a Request for Proposal (RFP) to develop
information for use in updating the City’s Seismic Hazards Identification Program (Ordinance
3666). See Staff Report 5293 “Discussion of Updating the Seismic Safety Chapter of the
Municipal Code for Hazardous Buildings” (Attachment D). The City Council approved the
recommendation and an RFP was prepared. A consulting team led by Rutherford + Chekene
was selected to:
A. Develop summarize relevant state and local seismic mitigation legislation
B. Obtain detailed information on Palo Alto’s existing building stock
C. Develop conceptual retrofits for vulnerable building types
D. Make loss estimates of expected damage to current and retrofitted building
E. Work with a City advisory group to develop policy recommendations for
consideration by the Council.
A stakeholder Advisory Group was convened and was an essential element in discussing
earthquake risks in Palo Alto’s existing building stock prepared by the consultant team and in
reviewing policy alternatives. Members included people with a range of relevant expertise
and interests, including interested citizens, earthquake risk and engineering experts, local
developers and owners, and representatives of various community groups. City
departments also participated in the Advisory Group, including Building, Planning, Fire,
Office of Emergency Services, and Public Works. See Attachment F for a list of Advisory
Group members.
City Policy Implications
Currently, the City is in the process of updating its Comprehensive Plan. In its Goal
statements, this document expresses the community’s vision for its future. Further, in its
policies, the Plan defines the appropriate actions to implement the vision. The Seismic Risk
Assessment Study’s findings and its guiding conclusions informed by the Seismic Risk
Management Advisory Group are integral to several key elements of the Comprehensive
Plan: the Safety Element, the Housing Element, and the approach to, and needs for,
coordinated Community Emergency Services. Policies being considered in the
Comprehensive Plan Safety Element support regular review and update of the City’s seismic
retrofit regulations.
Although focused on multiple family and commercial structures, the seismic risk assessment
identifies both the type of seismically vulnerable structures and the geographic areas in the
community that will be most affected by a major earthquake. To gage the impact, the study
looked at the cost of retrofitting each type of structure. It also evaluated the community
impact of the aftermath of a major earthquake in terms of loss of property and effect on the
City’s economy.
Palo Alto is currently participating with the other cities in the County in updating the State
and Federally mandated five-year update of the Santa Clara County Local Hazard Mitigation
Attachment E
City of Palo Alto Page 5
Plan (Santa Clara LHMP) as required by the Federal Disaster Mitigation Act of 2000. This
plan is required before Palo Alto can request FEMA assistance following a natural disaster.
The Local Hazard Mitigation Plan focuses on community mitigations to fire, flood and
earthquake events.
The data in the Seismic Risk Assessment Study will be useful as a tool to inform the Santa
Clara LHMP about the City’s needs in the event of a major earthquake. The Council’s
subsequent direction on revising of the City’s seismic renovation requirements will be
integrated into Palo Alto’s mitigations outlined in the Santa Clara LHMP plan.
The Seismic Risk Assessment Study and its implementation have important implications for
both City and emergency planning policy. First and foremost, the study provides valuable
information for the development of the City’s long range planning policy expressed in the
Comprehensive Plan in areas of community safety, housing, and coordination of community
services, which also includes community education and neighborhood volunteers. It also
provides information that can be used to refine the community’s vision regarding its
residents’ wellbeing and improve its preparedness for a major seismic event by addressing
risk to loss of life and property associated with vulnerable building types. The information
can also improve the community’s ability to recover from a major seismic event including
displacement of residents and businesses, loss of housing and commercial buildings and
community wide economic impacts and recovery.
Other policy implications involve the potential for displacement of existing uses and tenants
if building owners need to remove the uses/tenants to upgrade their buildings or if they
increase rents to cover the cost of engineering studies and retrofit work, and the how this
displacement can be minimized. Also, potential incentives for voluntary building retrofits
may need to be considered along with changes to the existing zoning incentives (Transfer of
Development Rights program) that grant bonus square footage to buildings that are
retrofitted downtown, and the potential impacts/benefits that might result from new
incentives or modifications.
SEISMIC RISK ASSESSMENT STUDY
The risk assessment carried out by R+C included a series of task reports. They have been
combined into one composite report as Attachment B and include surveys of state and local
seismic policies and practices, an inventory of buildings in Palo Alto, a summary of vulnerable
building categories, conceptual seismic retrofitting of representative vulnerable buildings, loss
estimates for the current condition of the building stock and if buildings are retrofit, a review of
past seismic retrofits in Palo Alto from selected City records, and a discussion of additional
recommended program features for an improved seismic risk mitigation program.
Table 1 summarizes the outcome of the seismic risk assessment and includes the Advisory
Group discussions. The table is organized around eight vulnerable building categories or
building types. Categories I, II and III encompass the identified vulnerable buildings for the
Attachment E
At
t
a
c
h
m
e
n
t
E
,,
Table 1: Summary of Recommended Policy Directions from the se1smic Risk Management Program Advisory Group
Category Approx. Building Date of Occupants Evaluation Voluntary, Deadlines for Evaluation Report and Disclosure Potential Incentives
Number Type Construction Report Triggered, or Retrofit Construction (years)1
Mandatory
Retroflt1
Current Program (Potential Revision In Italics)
I 10 Un-N/A Over6 Required Mandatory Report: Expired Website Fee waiver, expedited
reinforced (and over Construction: 2-4 listing and permitting, FAR bonus/
masonry l,900Sf} tenant trans/ er of development
II 4 Any Before 1/1/35 OverlOO Required Voluntary or Report: Expired notification rights (TDR)
Triggered Construction
Ill 9 Any Before 8/1/76 Over300 Required Voluntary or • Voluntary: Not required
Triggered • Triggered: At sole or renovation
Expanded Program
IV 294 Soft-story Before 1977 Any Required Triggered or Report: 2-4 Same as Fee waiver, expedited
wood Mandatory Construction above permitting, TOR, parking
frame • Triggered: At sale or renovation exemptions, permission to
• Mandatory: 4-6 add units
V 99 Tilt-up Before 1998 Any Required Triggered or Report: 2-4 Same as Same as Categories I, II and
Mandatory Construction above Ill
• Triggered: At sale or renovation
• Mandatory: 4-6
VI 37 Soft-story Before 1977 Any Required Voluntary, Report: 2-4 Same as Same as Categories I, II and
concrete Triggered or Construction above Ill
Mandatory • Voluntary: Not required
VII 35 Steel Before 1998 Any Required Voluntary, • Triggered: At sale or renovation
moment Triggered or • Mandatory: 6-8
frame Mandatory
VIII TBD Other older Before 1977 Any Not rec. at Not Report: N/A N/A N/A
non-ductile this time recommended Construction: NA
concrete at this time
'voluntary: Retrofit Is voluntary.
Triggered: Retrofit Is triggered when the building ls sold or undergoes substantial renovation.
Mandatory: Retrofit ls required per a fixed tlmellne.
2Deadllnes provide a potential range. Timellnes would vary depending on tiers or priority groupings of different subcategories.
City of Palo Alto Page 7
Figure 1: Category IV, Wood-frame Soft Story Building built before 1977 Earthquake Damage
Figure 2: Category I, Unreinforced Masonry Building Earthquake Damage
Figure 3: Category I, Unreinforced Masonry Building Earthquake Damage
Attachment E
City of Palo Alto Page 8
Survey of State and Local Seismic Policies
The risk assessment study includes two reports that address (1) a detailed review of the
seismic risk management policy context within the State of California including relevant
State legislation, and (2) the status of local seismic safety and mitigation programs.
Development of the reports included searches of legislative data bases, search and
review of published and online reports and materials, phone interviews with community
leaders as well as local and State government staff, and development of insights from
the consulting team based on their experiences in this arena. The two reports were
discussed at Advisory Group meetings and helped inform the development of potential
seismic risk management policies relevant to Palo Alto.
State Level Policy Review
The report on State level risk mitigation policies provides review of relevant historic and
pending State legislation related to seismic risk mitigation of vulnerable buildings. High
level legislative findings from the report include the following:
A. Palo Alto is affected by numerous relevant California existing laws and
regulations dating from the 1930s through the present. These laws regulate
many aspects of Palo Alto’s built environment, including certain classes of
building uses such as hospitals, public schools, and essential facilities; setting
code minimums for new construction; and mandating land use planning and real
estate disclosure measures for natural hazards including earthquakes.
Unreinforced masonry (URM) is at present the only structural system type for
which the State requires local jurisdictions to have a program.
B. If it so chooses, Palo Alto has wide authority to expand or strengthen its
approaches to seismic mitigation. The power to do more about earthquake
vulnerabilities is primarily in the hands of the local jurisdictions that have
significant discretion in the kinds of policies they can adopt.
C. Palo Alto has many additional actions it can take to make sure it is complying and
taking greatest possible advantage of State level regulations and opportunities.
In particular, opportunities exist now to align a new seismic program with two
ongoing mandated planning efforts the City is already engaged in: Palo Alto’s
Comprehensive Plan update and the Santa Clara County Local Hazard Mitigation
Plan update.
Based on what state laws allow and in some cases recommend policy directions Palo
Alto could pursue going forward include the following:
A. Implement measures to increase the effectiveness of its current program, for
instance by offering additional or larger incentives or devoting more resources to
program visibility and implementation
B. Expand the City’s current voluntary seismic mitigation programs to address
additional building types, uses, or sizes
Attachment E
City of Palo Alto Page 9
C. Add mandatory screening or evaluation measures for one or more vulnerable
building types such as soft-story wood frame or concrete buildings
D. Upgrade the City’s current voluntary URM program to make retrofitting
mandatory
E. Create a program that mandates seismic retrofits for one or more additional
(non-URM) vulnerable building types
F. Craft a program that combines any or all of the above measures. Local
precedents for all of these types of approaches exist
G. Continue the status quo current program
Local Program Best Practice Assessment
The local program best practices assessment report reviews current practices among local
jurisdictions and agencies that require seismic retrofitting. The report summarizes what has
been done legislatively and programmatically to increase awareness, assess, and motivate
mitigation of seismically vulnerable buildings.
Palo Alto is currently laying a solid foundation for future program development by investing
in new inventory and risk information as well as community outreach and internal staff
discussions. In doing so, it is joining a group of leading California coastal jurisdictions such as
Berkeley, Oakland, San Francisco and Los Angeles that have recently stepped up their
earthquake risk reduction efforts. San Leandro and Fremont have also had policies in place
for over a decade. While there is much learning and information sharing going on, each
jurisdiction has developed their own customized policy package. There is no single best
model that Palo Alto can straightforwardly adopt. Existing local approaches differ widely in
the following ways:
A. Policy mechanisms used to achieve progress
B. Scope of targeted building types or uses addressed
C. Prioritization for retrofit among vulnerable structures and compliance timeframes
D. Types of incentives offered to property owners
E. Disclosure measures used to increase public awareness
Policy Mechanisms
The policy mechanisms being used by other jurisdictions range from inventory only with no
subsequent requirements to mandatory retrofit completion in under five years. In between
are more gradual approaches such as voluntary retrofit advocacy, incentives, provisions that
make building deficiencies more visible to the public (disclosure measures), and mandatory
screening and evaluation requirements. An important policy decision is whether any
mandated actions are implemented on a fixed timeline or triggered at sale or at some
renovation cost threshold.
Attachment E
City of Palo Alto Page 10
Scope of targeted building types and characteristics
The most commonly addressed building type is unreinforced masonry (URM) construction
due to state law SB 547, passed in 1986. Over half of URM building programs in the state
require mandatory retrofit, often but not always, with a time frame on the order of ten to
twenty years. By 2006, seventy percent of all identified URM buildings statewide were
either demolished or retrofitted. Retrofit rates on average were three times higher in
jurisdictions with mandatory retrofit compared to voluntary programs. Jurisdictions used a
wide variety of both financial and policy incentives to assist URM building owners. Some
voluntary URM building programs coupled with incentives, including Palo Alto’s, have
achieved similar rates of success to mandatory programs.
More recent programs have focused on soft-story wood frame multi-family residential
buildings, including ten Bay Area jurisdictions and, most recently, Los Angeles as of 2015.
Soft-story wood frame building programs range in requirements from notification only to
mandatory retrofit. Several jurisdictions have innovatively used intermediate mandatory
screening and evaluation phases to further assess risk exposure and determine the final set
of buildings that will be affected by retrofit requirements. Soft-story wood frame programs
have largely been supported in the local community. Compliance timeframes in soft-story
wood frame programs tend to be short, on the order of two to seven years.
A comparatively small number of Southern California jurisdictions have acted to address
older concrete buildings, including Los Angeles, Burbank, Santa Monica, and Long Beach.
Non-ductile concrete frame and tilt-up concrete structures, in particular, are known to pose
serious risks. Programs aimed at older concrete buildings range from voluntary guidelines to
mandatory evaluation and full retrofit requirements. Timeframes on mandatory retrofit of
older concrete buildings vary greatly, from years to decades. Information about the
implementation and outcomes of these few programs is very limited.
Incentives
To complement program compliance requirements, jurisdictions can offer either financial or
policy oriented incentives. Financial incentives in increasing order of cost and
implementation difficulty include: waivers or reductions of building department fees, pass
through of retrofit costs to tenants (in jurisdictions with rent control), property-assessed
financing loads, subsidized or special term loans, real estate transfer tax rebates, special
district or historic designation tax reductions, tax credits, grants, and general obligation
bonds. Program incentives in order of increasing difficulty include exemption from future
retrofit requirements, expedited reviews, exemption or relief from standards or non-
conforming conditions, condominium conversion assistance, technical assistance for
retrofitting, zoning incentives, transfer of development rights, and density or intensity bonus
such as a floor area or floor area ratio bonus. Jurisdictions vary widely in the extent and type
of incentives offered, and many offer a number of different types of incentives.
Attachment E
City of Palo Alto Page 11
Disclosure Measures
Public disclosure provides a powerful mechanism for influencing the opinions and actions of
owners, renters, and buyers, particularly in programs without mandatory retrofitting
requirements. Officially publicizing a city’s concerns about deficiencies of a specific building
type could, for instance, change public opinion about the resale or rental value of listed
properties, an owner’s eligibility for refinancing or future loan terms, or the cost of
purchasing property and earthquake insurance.
Jurisdictions have used a variety of techniques to motivate attention to seismic risk
concerns.
Disclosure measures include the following:
A. Mandatory disclosure at time of sale: Sellers of property are required to disclose
features that could relate to earthquake performance.
B. Recorded notice on deed: Jurisdictions can record on the property title or deed, the
fact that the building is subject to additional requirements related to its seismic
vulnerability status.
C. Public listing of affected properties: Jurisdictions that operate web sites to describe
their programs can feature a full list of property addresses and the compliance status
of the property. Generally, owner names are not listed.
D. External signage: California law requires signage on all URM buildings. Similar
signage has been required since 2007 on soft-story wood frame buildings in the City
of Berkeley and non-complying soft-story wood frame buildings in San Francisco.
E. Tenant notification: Owners are required to present straightforward, standardized
information about the listed status of the property.
F. Earthquake performance rating systems: Owners can be either encouraged or
required to have their building rated on a standardized scale that classifies expected
performance in an earthquake. In 2015, the City of Los Angeles launched a voluntary
effort to encourage owners to rate the properties using the US Resiliency Council’s
rating system and pledged to rate its own public buildings. For more information
about the US Resiliency Council, see their website at <http://www.usrc.org/>.
Palo Alto Options
Based on the review of state and other jurisdiction policies, alternative program options
for Palo Alto were identified:
1. Status Quo: In this option, the existing ordinance with its mandatory evaluation,
voluntary retrofit approach remains in place without changes. Floor area ratio
bonuses are (were) available and could continue to be offered.
2. Increase Number of Building Types Regulated, but Retrofit Remains Voluntary:
Additional categories of structures are added to the mandatory evaluation
requirements beyond those of the current ordinance. These could include any or
Attachment E
City of Palo Alto Page 12
all of the building types discussed above, potentially also using additional location,
use, or occupancy criteria.
3. Increase Number of Building Types Regulated with Additional Disclosure Measures
Incorporated: This option would be similar to Option 2, but with increased use of
disclosure measures such as prominently posting the building list on the City
website, notifying tenants, requiring signage, and/or recording notice on the
property title.
4. Increase Number of Building Types Regulated, Some Building Types Have
Voluntary Retrofit and a Few Building Types Have Mandatory Retrofit, with
Enforcement by a Trigger Threshold: This option builds on Option 3, but
retrofitting would be required for some building types at whenever future time a
building is sold or undergoes substantial renovation above a set threshold.
5. Increase Number of Building Types Regulated, Retrofits for Some Categories are
Voluntary and a Few Categories are Mandatory, with Enforcement by a Fixed
Timeline: This option would be similar to Option 4, but retrofitting is required
according to a fixed timeline. Timelines and enforcement emphasis could vary
depending on tiers or priority groupings to motivate prompt action for the most
vulnerable or socially important structures.
6. Increase Number of Building Types Regulated, but More Categories are Required
to Have Mandatory Retrofits: This alternative is similar to Option 5, but retrofitting
would be required for additional categories on a fixed timeline.
Other Program Features and Implementation Factors
By updating its current ordinance, Palo Alto has a variety of opportunities to expand and
better link its earthquake mitigation program efforts to other City efforts in support of
community resilience goals. For instance, Palo Alto could encourage a building occupancy
and resumption program like San Francisco, encourage or fund installation of strong
motion instruments, or pursue special programs or requirements for cell phone towers,
facades, private schools, and/or post-earthquake shelter facilities. A detailed description
of several leading local program models and planning resources for these types of efforts
are included in Attachment B.
Building Inventory
Summary of Survey Methodology
One of the first steps in the Seismic Risk Assessment Study was to develop a digital
inventory of buildings in Palo Alto that includes all the information necessary to build the
exposure model for the loss estimate. Information sources used to develop the inventory
included county tax assessor files, City GIS files, a survey done by the Palo Alto Fire
Department and San Jose State University of soft-story wood frame buildings, field notes
from the building department files of selected buildings when the 1986 ordinance was
being developed, Google Earth and Street View visual reviews, and an extensive visual
sidewalk survey.
Attachment E
City of Palo Alto Page 13
After the sidewalk surveys and additional quality assurance refinements, the study
identified a total of 2,632 buildings in the study group for Palo Alto. This included 66
buildings subject to Palo Alto’s current seismic mitigation ordinance, because 23 of the
original 89 buildings subject to the ordinance have been demolished.
Not all buildings were field surveyed and not all key attributes needed for loss estimation
were available for all buildings. For buildings that were not surveyed and were missing
information, the missing attributes were developed using statistical comparisons with
buildings that were surveyed on a sector- by- sector basis. A multi-step procedure was
developed to fill in other missing attributes based on the best available comparative
information. As a result, while the information for buildings that were not surveyed may
not be fully accurate at the individual building level, the overall data set is seen as
sufficiently representative for the type of loss estimates used in the project and relative
comparisons made between different building types that are discussed ahead.
Replacement Cost Values for Palo Alto
In addition to the information discussed above, a locally-customized replacement cost
had to be established for each building. Standard 2014 RS Means Replacement Cost
values included in the project loss estimation software (Hazus) used were reviewed as a
starting point, but not considered representative for Palo Alto. R+C and Vanir
Construction Management prepared adjustments to RS Means values to capture 2016
data and local factors unique to Palo Alto. These were reviewed by a task group of the
City’s project Advisory Group that included local design professionals and developers
familiar with the local cost climate. The group recommended an increase of the values in
general and identified target values for selected common occupancies. Based on these
recommendations, R+C updated the values and Vanir reviewed them and revised the
non-targeted occupancies for estimating consistency. The resulting replacement costs
are shown in Table 2, and were used in the loss calculations. It is noted that resulting
costs are 1.7-2.6 times the RS Means-based Hazus default values (2014 cost data), and
that costs are intended to be representative of averages across the town.
Attachment E
City of Palo Alto Page 14
Table 2: Average $/SF replacement building cost by Hazus occupancy class.
Occupancy Class RS
Means
2014
Average
Palo
Alto
Cost1
[$/SF]
Market
Factor
for
Palo
Alto
Escalation
Factor
from 2014
costs to
2016
costs
Demo &
Minimal
Sitework
(5’
around
building)
[$/SF]
Soft Cost
Premium2
Average
2016
Palo
Alto
Cost w/
Soft
Costs
[$/SF]
Multiplier
(Replaced
with Soft
Costs / RS
Means)
Multi Family, duplex $130.75 40% 10% $17.50 20% $263 2.01
Multi Family, triplex/quad $114.94 40% 10% $17.50 20% $233 2.03
Multi Family, 5-9 units $206.41 40% 10% $17.50 20% $402 1.95
Multi Family, 10-19 units $194.12 40% 10% $17.50 20% $380 1.96
Multi Family, 20-49 units $212.26 40% 10% $17.50 20% $413 1.95
Multi Family, 50+ units $199.90 40% 10% $17.50 20% $390 1.95
Temporary Lodging $217.83 40% 10% $17.50 20% $424 1.94
Institutional Dormitory $234.44 50% 14% $25.00 20% $511 2.18
Nursing Homes $238.07 50% 12% $25.00 20% $510 2.14
Retail Trade $121.66 80% 10% $17.50 20% $310 2.55
Wholesale Trade $118.13 60% 10% $17.50 20% $$270 2.29
Personal & Repair Services $143.47 60% 10% $17.50 20% $324 2.26
Professional/Technical/ Business
Services
$194.52 65% 12% $17.50 20% $452 2.33
Banks $281.88 40% 12% $25.00 20% $560 1.99
Hospitals $372.59 50% 14% $35.00 20% $807 2.16
Medical Office/Clinics $267.85 20% 10% $17.50 20% $445 1.66
Entertainment/Recreation $248.61 25% 12% $25.00 20% $448 1.80
Theaters $186.45 35% 12% $25.00 20% $368 1.98
Parking $84.59 20% 10% $17.50 20% $155 1.83
Heavy $144.71 25% 10% $17.50 20% $260 1.80
Light $118.13 25% 10% $17.50 20% $216 1.83
Food/Drugs/Chemicals $229.48 30% 12% $17.50 20% $422 1.84
Metal/Minerals Processing $229.48 30% 12% $17.50 20% $422 1.84
High Technology $229.48 40% 14% $17.50 20% $461 2.01
Construction $118.13 30% 10% $17.50 20% $224 1.89
Church $118.13 50% 12% $25.00 20% $268 2.27
Agriculture $199.08 10% 12% $17.50 20% $315 1.58
General Services $152.63 40% 10% $17.50 35% $341 2.23
Emergency Response $259.52 40% 14% $25.00 35% $593 2.28
Schools/Libraries $193.00 40% 12% $25.00 35% $442 2.29
Colleges/Universities $214.91 60% 12% $25.00 35% $554 2.58
Notes:
1. RS Means average cost includes RS Means default location factors to adjust national average to Palo Alto of 15% for
residential and 11% for commercial.
2. Soft costs include architect and engineer design fees, testing and inspection, utility connection fee, permits, and an
allowance for owner change order contingency.
3. Costs are intended to be representative of average in Palo Alto across the town, including downtown areas together
with other areas in the city.
4. Costs were previously prepared following a 3/7/2016 discussion with the Palo Alto Seismic Risk Program Advisory
Group Technical Advisory Committee. Table includes minor updates based on internal review between
Attachment E
City of Palo Alto Page 15
Rutherford + Chekene and Vanir Construction Management to achieve improved relative ratios between
different occupancy types.
Number and Distribution of Vulnerable Buildings by Aggregate Size and Value
Table 3 shows how the number and aggregate value of Palo Alto’s buildings is distributed
by type of structure, using the FEMA Model Building Type classification system for
structural system. The table is sorted by aggregate building value. Wood frame buildings
make up about 60% of the number of buildings and represent 35% of the total value.
About 20% of the buildings are concrete, and they represent over 40% of the total value.
Of the remaining 20%, about two-thirds are masonry buildings, and one-third steel.
However, the steel buildings represent about twice the value of the masonry buildings.
Attachment E
City of Palo Alto Page 16
Table 3: Distribution of number of buildings, building area,
and building value by Model Building Type.
Model Building Type Number of
Buildings
Aggregate Square
Feet (1,000)
Aggregate Building
Value ($M)
Concrete shear wall (C2) 318 9,699 4,082
Concrete tilt-up (PC1) 242 8,054 3,368
Wood frame larger residential (W1A) 331 8,403 3,232
Wood frame commercial/industrial (W2) 307 6,209 2,369
Steel braced frame (S2) 50 3,116 1,391
Wood frame smaller residential (W1) 898 3,821 1,278
Steel moment frame (S1) 75 3,005 1,242
Reinforced masonry, wood floor (RM1) 285 2,806 1,209
Reinforced masonry, concrete floor (RM2) 30 574 211
Steel light metal frame (S3) 41 533 177
Precast concrete frame (PC2) 5 334 125
Concrete moment frame (C1) 18 325 117
Steel frame with concrete shear walls (S4) 13 162 72
Unreinforced masonry bearing wall (URM) 9 274 15
Concrete with masonry infill (C3) 8 26 8
Steel frame with masonry infill (S5) 2 6 3
Totals 2,632 47,346 18,899
The study group of buildings can be further divided into age groups separated by
significant milestones in building code implementation. The following age groups were
selected: pre-1927, 1927-1961, 1962-1976, 1977-1997, and 1998 to present. The
milestones reflected include the first earthquake code in Palo Alto in 1926, adoption of
the 1961 Uniform Building Code (UBC) and associated more stringent design
requirements, code changes in the 1976 UBC following the 1971 San Fernando
Earthquake, and code changes in the 1998 UBC following the 1994 Northridge
Earthquake. Figure 1 shows a histogram of the year built of the buildings in the study
group.
Attachment E
City of Palo Alto Page 17
Figure 1: Distribution of year built of buildings in study group with significant changes in the
building design practice.
Vulnerable Building Categories
One of the important tasks in the risk assessment study was to identify potentially
vulnerable building categories specific to Palo Alto. Using the building inventory that was
developed early in the project, R+C identified potentially vulnerable structural system
types based on insights from past earthquake events, milestone improvements in seismic
code requirements made in Palo Alto, rankings in prominent seismic risk assessment tools
such as the 2015 edition of FEMA P-154 Rapid Visual Screening of Buildings for Potential
Seismic Hazards, results from past seismic risk assessment studies in California
communities, and engineering judgment. The building categories were then evaluated in
analytical loss estimate studies, described ahead, which helped to narrow in on the most
important categories for Palo Alto. Key building vulnerability metrics include the risk of
deaths and injuries, the cost of damage, and the extent of downtime or loss of use.
Buildings in the identified vulnerable building categories tend to perform poorly with
respect to all three of these metrics though the relative degree of vulnerability to each
factor varies.
Attachment E
City of Palo Alto Page 18
Community Resilience
Community resilience is improved if residents have homes that remain usable after an
earthquake and if businesses can still operate. From a program perspective, the consultant
team and advisory group believe that the greatest reduction in losses and the largest benefit
to community resilience will come from seismically retrofitting building types known to be
both potentially hazardous and present in significant numbers in Palo Alto. .
In addition to the three categories already in Palo Alto’s seismic hazard identification
ordinance (Categories I, II, and III below), five additional categories of vulnerable building
types were identified. All five categories meet the criteria of being potentially hazardous
and having a significant presence in Palo Alto. The eight categories and the approximate
number of buildings included in each category are as follows:
1. Category I: Constructed of unreinforced masonry, except for those small than 1,900
square feet with six or few occupants (10 remaining buildings in Palo Alto)
2. Category II: Constructed prior to January 1, 1935 containing 100 or more occupants
(4 remaining buildings)
3. Category III: Constructed prior to August 1, 1976 containing 300 or more occupants
(9 remaining buildings)
4. Category IV: Pre-1977 soft-story wood frame (294 buildings)
5. Category V: Pre-1998 tilt-up concrete (99 buildings)
6. Category VI: Pre-1977 concrete soft-story (37 buildings)
7. Category VII: Pre-1998 steel moment frame (35 buildings)
8. Category VIII: Other pre-1977 concrete construction (170 buildings)
The technical assessment confirms that the potential reduction in losses from retrofitting is
significant for these categories.
Conceptual Seismic Retrofitting of Representative Vulnerable Buildings
Retrofit was considered for all buildings that have not already been retrofitted and were
either constructed before 1961 or between 1962 and the “benchmark” year with a soft
story. A “benchmark” year is when the code requirements for that building type became
similar to those currently in place. Consistent with typical practice, the performance of the
retrofitted buildings in an earthquake is assumed to be less than that of newly constructed
buildings.
Attachment E
City of Palo Alto Page 19
For estimating the cost of retrofit for the improved buildings, R+C developed conceptual
designs for Model Building Types that represent a significant number and value of Palo Alto’s
building stock, as well as a significant loss and loss reduction after retrofit. This process
identified wood frame (W1, W1A, W2), steel moment frame (S1), concrete shear wall (C2),
concrete tilt-up (PC1), and reinforced masonry (RM1) and unreinforced masonry (URM) as
appropriate candidates. For each Model Building Type, the age, square footage and number of
stories were reviewed to identify a “prototype” building. In cases where the prototype building
was not representative of more than two-thirds of the total number of buildings, multiple
prototypes were considered.
Figure 2: Retrofit scheme for Large Multi-family Soft-Story Wood Frame Building.
An example of a conceptual retrofit for the W1A prototype building is shown in Figure 2
from a 2000 brochure by R+C for the City of San Jose entitled “Practical Solutions for
Improving the Seismic Performance of Buildings with Tuck-under Parking.” The retrofit
elements were keyed to representative details in 2006 FEMA 547 Techniques for the Seismic
Attachment E
City of Palo Alto Page 20
Rehabilitation of Existing Buildings, and a written description of collateral impacts was
developed as well to provide sufficient detail to allow a rough order of magnitude cost
estimate to be prepared.
The cost estimators of Vanir Construction Management used the conceptual designs to
estimate a range of probable cost to implement the retrofits. The retrofit costs for each
prototype building are shown in Table 4. These costs include hard costs, which are the costs
the owner pays the contractor, plus a design contingency since these are conceptual
retrofits. The estimate further includes soft costs, representing architect and engineer
design fees, testing and inspection costs, permit fees, and an owner change order
contingency.
Considered costs do not include hazardous material abatement, costs associated with
performing the work while occupants are using the building, triggered accessibility upgrades,
cost premiums associated with retrofit of a historic building, tenant relocation or business
interruption during construction, project management, renovation, financing, repair of
existing conditions, and legal fees. These costs are more variable and project and site
specific, and are typically not included in loss estimates for this type of study.
The retrofit costs were extrapolated to Model Building Types not represented by a prototype
retrofit as shown in the fifth column of Table 4.
Additional information the conceptual retrofits and their estimate cost is contained in
Attachment B.
Attachment E
City of Palo Alto Page 21
Table 4: Conceptual retrofit cost.
Retrofit
Prototype
Model Building Type Stories Square
Feet
Used for
Model
Building
Types
Used for
Square
Feet
Average
Retrofit
Cost
($/SF)
1 Wood frame smaller
residential (W1)
2 5,320 W1 All 12
2 Wood frame larger
residential (W1A)
2 9,500 W1A < 15,000 11
3 Wood frame larger
residential (W1A)
3 30,000 W1A ≥ 15,000 6
4 Wood frame
commercial/industrial (W2)
2 10,000 W2 All 14
5 Steel moment frame (S1) 2 43,900 S1, S2, S3 All 10
6 Concrete shear wall (C2) 1 5,000 C1, C2, S4,
PC2
< 10,000 50
7 Concrete shear wall (C2) 2 17,280 C1, C2, S4,
PC2
≥ 10,000 40
8 Concrete tilt-up (PC1) 1 18,435 PC1 < 25,000 29
9 Concrete tilt-up (PC1) 2 38,400 PC1 ≥ 25,000 21
10 Reinforced masonry, wood
floor (RM1)
1 2,750 RM1, RM2 < 5,000 74
11 Reinforced masonry, wood
floor (RM1)
2 8,150 RM1, RM2 ≥ 5,000 46
12 Unreinforced masonry
bearing wall (URM)
1 5,000 URM, S5, C3 All 110
Attachment E
City of Palo Alto Page 22
Loss Estimate Findings for Current Condition
Hazus is a geographic information system (GIS) based, standardized, nationally applicable
multi-hazard loss estimation methodology and software tool. It is used by local, state, and
federal government officials for preparedness, emergency response, and mitigation
planning. The Advanced Engineering Building Module from the latest Hazus version 3.1 was
used to conduct the loss estimates in the study so that individual buildings could be analyzed
using the specific inventory data collected for Palo Alto.
Analyses were conducted for two specific earthquake scenarios developed by the United
States Geological Survey (USGS): a major M7.9 San Andreas Fault event, and a strong M6.7
San Andreas Fault event.
Contour plots for the short period spectral acceleration for the two M6.7 and M7.9 scenarios
are shown in Figure 3. Spectral acceleration is a measure of the building response to shaking
at the site.
Figure 2: Predicted short period spectral acceleration in vicinity of Palo Alto (city boundary
shown) for two selected San Andreas Fault scenarios.
Attachment E
City of Palo Alto Page 23
Estimated Losses for Buildings in Their Current Condition
Table 5 summarizes the total loss calculated by Hazus for the as-is condition for the two
earthquake scenarios. The results show that the estimated losses to Palo Alto buildings
and contents in a M6.7 scenario will be significant, on the order of $1.2 billion. Though
ground shaking in the M7.9 scenario is only about 25% larger than it is in the M6.7
scenario, overall building and content losses double to $2.4 billion. Average building
damage and content damage also approximately double with a M7.9 event. The
difference in the number of buildings that are heavily damaged with the larger
earthquake is more pronounced with a 12-fold increase from the M6.7 to the M7.9
scenarios. This is shown in the fourth column of Table 5 as the number of buildings with a
damage ratio exceeding 20%.
Table 5: Total losses for study group in as-is condition.
Earthquake
Scenario
Building
Value1
($B)
Content
Value2
($B)
Number of
Bldgs.
with
Damage
Ratio ≥
20%3
Estimated
Building
Damage4
($B)
Estimated
Content
Damage4
($B)
Total
Building
and
Content
Damage
($B)
M7.9 18.9 17.3 224 1.7 0.7 2.4
M6.7 18.9 17.3 19 0.8 0.4 1.2
Ratio of M7.9/M6.7 2 2 2
Notes:
1. Building value is the complete replacement cost for the building, and
includes the structure, architectural, mechanical, electrical, and plumbing
components (e.g., ceilings and lighting).
2. Content value includes the complete replacement cost of furniture and
equipment that is not integral with the structure (e.g., computers and
other supplies). They are estimated as a percent of structure replacement
value, dependent on occupancy.
3. Damage ratio is defined as the cost of repairing damage divided by the
replacement cost of the building.
4. Estimated building and content damage cost is the cost associated with
repair and replacement of the building and its content.
To put the loss from building damage in context, the average annual valuation of Palo
Alto construction permits was $400M between 2013 and 2016 (which represents a boom
period). The total loss of $1.7B in a major M7.9 earthquake represents more than four
years’ worth of construction, and the total loss of $0.8B in a strong M6.7 earthquake
represents more than two years’ worth of construction.
It should be noted that these losses do not include the effects of lives lost and business
disruption, or the ripple effects in the local economy or real estate market. Much of this
loss will not be insured.
Attachment E
City of Palo Alto Page 24
Estimated Losses by Building Type
It is important to look at multiple metrics when deciding which buildings are the most
vulnerable and significant to the community as a whole. Table 6 breaks out the estimated
loss and damage ratio for various model building types, and it can be seen that it depends
on the metric used which building type is considered the poorest performer. Looking at
the total loss alone, concrete bearing wall buildings and commercial wood frame
buildings are responsible for the highest total loss. This tracks well with the earlier
finding that these structural systems are the most prevalent ones. If we look at the
highest average building damage ratio instead, buildings with unreinforced masonry
bearing walls and unreinforced masonry infills are the most prone to damage. However,
not very many of them exist in Palo Alto, and as a result they do not represent much of
the aggregate loss.
Additional information on the loss estimate for the existing building stock is contained in
Attachment B.
Table 6: Top three vulnerable building types ranked by total loss, average damage ratio,
and number of severely damaged buildings.
Building Type Number
of
Buildings
Building
Value
($M)
M7.9 EQ
Total
Building +
Content
Losses
($M)
M7.9 EQ
Average
Building
Damage
Ratio
M7.9 EQ
Number
of
Bldgs.
with
Damage
Ratio ≥
20%
Concrete shear wall (C2) 318 4,082 477 14% 75
Concrete tilt-up (PC1) 242 3,368 365 12% 32
Wood frame commercial/industrial (W2) 307 2,369 216 9% 9
Steel frame with masonry infill (S5) 2 3 1 38% 1
Unreinforced masonry bearing wall (URM) 9 15 4 29% 9
Concrete frame with masonry infill (C3) 8 8 2 29% 6
Concrete shear wall (C2) 318 4,082 477 14% 75
Concrete tilt-up (PC1) 242 3,368 365 12% 32
Steel moment frame (S1) 75 1,242 130 18% 27
Loss Estimate Findings with Buildings Retrofitted
A second Hazus AEBM run was done assuming a retrofitted building stock. For this model
run, it was assumed that a building would be retrofitted if it has not already been
retrofitted and was either constructed before 1961 or between 1962 and the benchmark
year with a soft story. The Hazus model was rerun with the updated properties
simulating retrofit.
Attachment E
City of Palo Alto Page 25
Table 7 shows the resulting total losses and damage ratios after buildings have been
retrofitted. Though total losses are still significant, comparing the results of Table 7 with
Table 5 shows a reduction in total loss of 45% for the M7.9 scenario, and 33% for the
M6.7 scenario. In other words, aggregate loss to the community if all considered
properties were retrofit could be reduced by one third in a very plausible event and
almost halved in a much larger event.
Another important improvement is the reduction of the number of buildings with more
than 20% damage. The M7.9 scenario shows a reduction from 224 buildings to 6
buildings. This means that the probability of building collapse and resulting injuries and
fatalities has become very low.
Finally, the damage and loss of the M7.9 scenario remain approximately two times the
amount of loss sustained in the M6.7 scenario. This suggests that the retrofit has a
similar impact for both levels of ground shaking.
Table 7: Total losses after retrofitting.
Earthquake
Scenario
Building
Value
($B)
Content
Value
($B)
Estimated
Building
Damage
($B)
Number
of Bldgs.
with
Damage
Ratio ≥
20%
Estimated
Content
Damage
($B)
Total
Building
&
Content
Damage
($B)
M7.9 18.9 17.3 0.9 6 0.5 1.3
M6.7 18.9 17.3 0.5 0 0.3 0.8
Ratio of M7.9/M6.7 2 - 2 2
Table 8 breaks out the reduction in total loss by model building type for the M7.9
scenario, and shows the associated retrofit cost. The average reduction in loss varies by
building type. URM buildings showed the highest reduction in loss after retrofit as a
percentage of the loss itself. Steel braced framed buildings showed the lowest reduction
in losses as a percentage of the loss itself. Wood frame and concrete buildings are
responsible for the largest reduction in total loss, with wood frame construction
representing over 20% of the loss reduction, and concrete buildings over 50%.
It should be noted that the data in Table 8 also includes buildings that were not retrofitted. As
a result, further parsing of the data is needed to better understand which buildings are
responsible for the most loss, and those that can be improved more cost-effectively.
Table 8: Comparison of retrofit benefits and costs by Model Building Type.
Model Building Type M7.9 EQ M7.9 EQ Average Retrofit
Attachment E
City of Palo Alto Page 26
Average
Damage
($/SF)
Total
Damage
Reduction
($1,000)
Damage
Reduction
($/SF)
Cost
($/SF)
Wood frame smaller residential (W1) 16 13,775 4 12
Wood frame larger residential (W1A) 25 61,317 7 6-11
Wood frame commercial/industrial (W2) 50 160,155 26 14
Steel moment frame (S1) 62 76,150 25 10
Steel braced frame (S2) 44 24,222 8 10
Steel light metal frame (S3) 108 38,163 72 10
Steel frame with concrete shear walls (S4) 101 11,118 69 40-50
Steel frame with masonry infill (S5) 247 695 121 110
Concrete moment frame (C1) 55 8,045 25 40-50
Concrete shear wall (C2) 70 336,574 35 40-50
Concrete frame with masonry infill (C3) 120 865 34 110
Concrete tilt-up (PC1) 68 218,491 27 21-29
Precast concrete frame (PC2) 21 0 0 21-29
Reinforced masonry, wood floor (RM1) 59 87,697 31 46-74
Reinforced masonry, concrete floor (RM2) 35 3,727 6 46-74
Unreinforced Masonry Bearing Wall (URM) 23 5,216 19 110
Totals 51 1,046,210 22
Table 9 shows those types of buildings that may be considered good candidates for a
retrofit program. Although representing only about 15% of the total inventory, these
buildings are responsible for over 30% of the total loss. This is reflected in the
considerably higher than average loss (fourth column of Table 9). The benefit of retrofit is
also considerable for this group of buildings, since they are responsible for over 50% of
the reduction in loss. Additionally, the cost to retrofit them is only a fraction of the losses
avoided in a major event, ranging from a third for the concrete buildings to a tenth for
the steel frames. Note that these values are based on conceptual retrofits. Actual
retrofit costs for individual buildings would vary substantially. The steel moment frame
benefit-to-cost ratio is higher than expected by engineering judgment, caused in part by a
comparatively low retrofit cost for this Model Building Type.
Additional information on the loss estimate for the retrofitted building stock is contained
in Attachment B.
Table 9: Comparison of benefits and costs by selected
Model Building Type, date and characteristics.
Model Building Type Number
of
Buildings
Total
SF
(1,000)
M7.9 EQ
Average
Loss by
M7.9 EQ
Average
Loss
Average
Cost to
Retrofit
(Average
Loss
Avoided)
Attachment E
City of Palo Alto Page 27
Building
($/SF)
Avoided
by
Retrofit
($/SF)
($/SF) /
(Average
Retrofit
Cost)
Pre-1977 wood frame soft-
story (W1, W1A, W2)
294 3,690 66 46 12 4
Pre-1998 tilt-up (PC1) 99 3,078 106 71 23 3
Pre-1977 concrete soft-story
(C1, C2, C3)
37 842 149 108 42 3
Pre-1998 steel moment frame
(S1)
35 690 152 110 10 11
Review of Past Seismic Retrofits
To gain a better understanding of the quality of the retrofits and identify relevant issues to
updating Palo Alto’s seismic risk mitigation program, a sample of the submitted engineering
studies and building retrofits drawings for existing buildings was reviewed.
The review identified the following relevant needs for future seismic risk mitigation
programs:
A. Clear identification of retrofit design intent, scope, and limitations, also for voluntary
retrofits
B. Identification of existing structural systems
C. Decision on requirements for buildings that have had partial seismic retrofits
completed; and may have remaining seismic deficiencies
Attachment E
City of Palo Alto Page 28
Additional Recommended Program Features
In addition to expansion of the building categories included within the City’s seismic risk
mitigation program and refinement of disclosure measures and incentive options, a number
of other program features are recommended. They are described in Attachment B, and
include the following:
A. Use the current inventory, taking note of its limitations - The inventory developed for
the effort to date involved use of digital information and field surveys. A complete
field survey of all buildings in Palo Alto was outside the scope of the project.
However, the inventory that has been developed is an excellent resource. The first
step in any future ordinance will involve notification of building owners that they
may be subject to the requirements of the ordinance. Those buildings that were field
surveyed and fall within the scope of the ordinance can be notified using the existing
inventory. For the remaining buildings, additional field survey is recommended. This
would be a rapid visual assessment and could be conducted by City staff or outside
consultants.
B. Use an initial screening form phase - Typically, as part of the notification process, a
screening form of about one page in length is sent, and the owner is required to have
a design professional, such as a structural engineer or architect, complete the form.
This cost for to confirm whether or not the building actually is subject to the City’s
ordinance should be relatively nominal.
C. Clearly specify seismic evaluation and retrofit scope - For all buildings subject to
regulation, the seismic evaluation (and retrofit) methodology for each building
category will need to be defined. Industry consensus standards exist and cover the
vulnerable building categories identified for Palo Alto. These include the 2015
International Existing Building Code (IEBC) and 2014 ASCE 41-13 Seismic Evaluation
and Retrofit of Existing Buildings. Both are currently being updated by groups of
engineers and building officials. For soft-story wood frame buildings, there is also the
2012 FEMA P-807 Seismic Evaluation and Retrofit of Multi-Unit Wood-Frame
Buildings with Weak First Stories. For steel moment frame buildings, there is also the
2000 FEMA 351 Recommended Seismic Evaluation and Upgrade Criteria for Existing
Welded Moment Resisting Steel Structures. The following table provides
recommended evaluation and retrofit standards.
D. Provide detailed evaluation report submittal requirements - Minimum submittal
requirements for evaluation reports will need to be defined. The above evaluation
and retrofit standards provide some guidance but a short clear set of requirements
will be beneficial.
E. Specify how past partial retrofits will be handled: In the past, some buildings have had
partial seismic retrofits where only selected portions of the seismic force-resisting
system have been upgraded; Some seismic deficiencies may still exist in these
structures. If mandatory retrofit requirements are implemented that provide for
comprehensive retrofitting of the full seismic load path, there may be buildings with
previous partial retrofits that do not fully comply and need remaining deficiencies to
Attachment E
City of Palo Alto Page 29
be addressed. The seismic evaluation reports will help identify these cases.
F. Update both new and existing building permit submittal requirements: Review of City
records found that basic information such as the building structural system, date of
construction, and retrofit standard used (where applicable) are not readily available.
It is recommended that submittals for permit for both new buildings and existing
building renovations require this information. This will allow the city to have a much
better understanding of its total building stock and its expected performance in an
earthquake.
G. Write a new ordinance or set of ordinances to update the program: After the Council
has provided direction and the above issues have been addressed, an updated
ordinance will need to be written.
H. Carefully address program management and interdepartmental coordination needs:
To successfully manage Palo Alto’s updated Seismic Risk Mitigation Program, an
effective management plan is needed so that progress is monitored by the City and
community intent is achieved.
I. Delineate department and key staff responsibilities: For Palo Alto’s updated Seismic
Risk Mitigation Program, City staff will be responsible for several categories of
activities. These will include the basic activities such as managing the notification and
inventory process, reviewing evaluation reports and plan checking retrofit
construction documents, and field inspections of retrofit work. Less obvious activities
will include evaluating requested exceptions to the program or alternative means of
compliance; managing feedback from design professionals, owners, and the public;
tying pre-earthquake retrofitting to post-earthquake safety evaluations records; and
managing post-earthquake safety evaluation, repair, and recovery plans. Depending
on the scale of the updated program, it is possible that additional staff members,
consultants, and/or an appropriately experienced structural engineer may be needed
to provide advice on technical and program management issues, particularly as the
program moves to final definition and to initial implementation. Later, as is done in
some communities, it may be desirable to create volunteer review boards of local
structural engineers who review questions on the evaluation and retrofit criteria and
provide the City with technical opinions that staff can use.
Attachment E
City of Palo Alto Page 30
Table 10: Recommended Evaluation and Retrofit Standards.
Category Description Evaluation and Retrofit Standards
I Unreinforced masonry IEBC Appendix Chapter A1
II Built before 1/1/35 with 100 or
more occupants
ASCE 41
III Built before 8/1/76 with 300 or
more occupants
ASCE 41
IV Pre-1977 soft-story wood
frame
IEBC Appendix Chapter A4, ASCE 41, or FEMA P-807
V Pre-1998 tilt-up IEBC Appendix Chapter A2 and ASCE 41
VI Pre-1977 soft-story concrete ASCE 41
VII Pre-1998 steel moment frame ASCE 41, or FEMA 351
VIII Other pre-1977 concrete ASCE 41
ADVISORY GROUP INPUT
Summary Report of the Advisory Group
The purpose of convening an Advisory Group composed of members with local expertise and
construction experience was not to create a consensus document or ratify particular
recommendations by majority vote. Instead, the goal was to educate, solicit, and explore
the range of issues and opinions among interested parties who participated. A summary
report, reviewed by all the members of the Group, was prepared to document their input in
to the study (Attachment G). The Advisory Group was a first step in community engagement
regarding seismic hazard reduction in Palo Alto. It was intended that the information in the
Advisory Group’s summary memo would be provided to the City Council as they consider
potential revisions to the City of Palo Alto’s seismic risk management program and seismic
hazard identification ordinance.
Preferred Policy Directions
In summary, discussions with the Advisory Group revealed little to no support for
maintaining the status quo. Strong support did exist for retrofitting buildings already in
the program, particularly URM buildings, and for addressing more building types,
particularly soft-story wood frame buildings and older concrete tilt-ups.
For buildings addressed in the current ordinance, the group generally thought a
mandatory retrofit requirement would be feasible and fair. Three decades later, market
forces alone have clearly not been enough to motivate upgrade of these remaining
structures. Because the barriers to retrofit work for these properties are not known,
case-by-case management by City staff may be necessary. There was hesitance, however,
about extending or increasing incentives for owners that had not voluntarily taken
advantage of the FAR bonus available in the past.
More detailed conversations took place about other building category priorities and
Attachment E
City of Palo Alto Page 31
policy features focused on extending the vulnerable building types they addressed and
the requirements for retrofit compliance. These program alternatives are incorporated
into Options 3, 4, and 5 (see the “Survey of State and Local Seismic Policies” section). The
Advisory Group was briefed on structural types generally known to be vulnerable that are
common or significant to Palo Alto and estimated to have reasonable loss reduction to
retrofit cost ratios. The Group’s goal was to focus on a subset of categories that seemed
to have high potential to benefit the owner, occupants, and the broader community.
Some participants showed greater concern about residential properties, and debated
whether commercial and residential properties should be treated the same or differently.
The Advisory Group showed high interest in addressing multi-family residential
earthquake risks, in particular by starting a soft-story wood frame program as many other
California cities have done. One soft-story wood frame program approach discussed was
to have two phases: 1) owners following notification would be given several years to do a
voluntary retrofit, along with more generous incentives; and 2) later a mandatory
timeline would kick in and incentives would be phased out. The group noted that
exemptions such as parking requirements, permission to add other unit(s), or the ability
to transfer development rights for additional square footage would likely be attractive
and useful incentives for the multi-family soft story building type.
Other vulnerable building categories of concern were also reviewed, including pre-1977
tilt-up concrete structures. There are a modest number of these buildings in Palo Alto,
but Advisory Group members noted that their uses are changing. Many buildings
previously used as warehouses are now being repurposed for office space. The higher
occupancies increase the public safety stakes of any seismic deficiencies. Currently, there
is no mandate in the regulations to address earthquake vulnerabilities while other
upgrades and build out are being done to these structures. A substantial renovation
trigger mandate might make sense, but the percent of the value of the structure used as a
trigger might need to be lowered in order to get compliance. Such properties with more
than one story should perhaps receive higher priority for retrofit.
Potential Issues for Future Study and Consideration
For some issues, based in part on Advisory Group discussions, additional information may
be beneficial to help develop a strategy and to better understand potential impacts on
key stakeholders and community concerns. Some of these issues are primarily economic
and were outside the scope of the current study. The City Council may wish to direct staff
and/or outside consultants to investigate some of these items in more detail as the
seismic risk management program effort proceeds. These issues include the following:
A. Occupants and tenants
a. How much would a typical retrofit add to the monthly rent of a multifamily
Attachment E
City of Palo Alto Page 32
soft-story wood frame apartment tenant?
b. Would some tenants be unable to afford a rent increase and seek housing
elsewhere in Palo Alto or move outside the city (and if so, how many might
be displaced)?
c. If soft-story wood frame apartments in Palo Alto are retrofitted in time
before the next major earthquake, how much less displacement of
residents would occur as a result of the earthquake?
d. What categories of buildings are most important to address in order to
help maintain the commercial viability and vitality of the City’s core
business districts and tax base?
B. Property owners, developers, and business owners
a. What are the characteristics of property owners that would be affected?
b. How might small businesses be affected compared to larger ones?
c. How many property owners are in need of lower cost capital or other
substantial financial assistance to fund retrofitting?
C. Impacts of Seismic Restoration on Retention of Historic Structures in the City
a. How can we ensure that the review of initial seismic evaluations identify
those structures that are listed in the City’s Historic Inventory or
potentially significant and flag them for attention during subsequent
review?
b. How can we develop a clear process for reviewing proposed seismic
retrofits to historic structures that is coordinated among responsible city
departments and is consistent with current regulations and Community
policies?
c. How can we ensure that property owners take advantage of Seek out
retrofit alternatives that are consistent with the Historic Building Code,
historic characteristics of the structure, and provide the required most risk
reduction?
D. City departmental resources and budgets
a. What would be the loss in revenue to the Building Department if fee
waivers were offered?
b. What would be the staffing and budgetary needs over time to administer
an expanded program that addresses additional building types?
c. What kinds of interdepartmental cooperation and staff resources in other
departments are necessary to ensure effective implementation and
coordination with other city planning and public safety efforts?
d. What would be the costs to provide and administer any incentives offered
to property owners?
E. Overall community economic health
a. What kind of benefits could accrue to Palo Alto in terms of maintaining
community function and ability to recover if various building categories are
retrofitted in time before the next major earthquake?
F. Other related issues
Attachment E
City of Palo Alto Page 33
a. It was brought up in the Advisory Group that the Building Department
needs flexibility and authority to take steps to get tough seismic mitigation
projects done. One idea was to grant the Building Official the ability to
classify certain projects (with well-specified criteria) as warranting a kind of
“seismic safety” or “earthquake resilience” fast tracking, with city
departments agreeing to coordinate on a specified accelerated project
review timeframe.
b. Although outside the formal scope of this planning effort, several Advisory
Group members commented that it would be desirable for the City to do
some kind of assessment of any earthquake mitigation needs in public
buildings and facilities serving the City.
c. Advisory group members recommended the community be informed of
Palo Alto’s overall potential seismic risk by providing a summary of
potential impacts on the City’s website, including the expected
performance of vulnerable buildings.
d. The group also had a high degree of support for recommending that the
City initiate and nest future earthquake mitigation programs within a
broader disaster or community resilience initiative, as cities such as Los
Angeles, Berkeley, and San Francisco have done. This could be
incorporated into the update of the City’s Comprehensive Plan Safety
Element. There was insufficient time in the project’s six advisory group
meetings to consider potential initiatives to assess risks for cell phone
towers, water supply, facades, private schools, post-earthquake shelter
facilities, and/or other assets important to community recovery.
TIMELINE
The timeline for updating the current seismic mitigation regulation is dependent on Council’s
review of the Seismic Risk Assessment Study and directions to staff.
RESOURCE IMPACT
Implementation of the report recommendations would result in additional costs to private
property owners and prior to any decision to proceed, staff is proposing additional public
outreach at a cost of about $50,000. Technical requirements and design guidelines to support
a new ordinance would require additional consultant services at an estimated cost of $50,000.
If desired, an analysis of the fiscal impact on residents and business could be prepared for an
additional $50,000. Any incentives offered to building owners could also have a cost to the
City, which would not be known until those incentives are further defined.
ENVIRONMENTAL REVIEW
The preparation of the Seismic Risk Assessment Study is exempt from environmental review
under the California Environmental Quality Act (CEQA) Guidelines Section 15306 (Information
collection leading to an action which a public agency has not yet approved, adopted, or
funded).
Attachment E
City of Palo Alto Page 34
TABLE OF CONTENTS FOR ATTACHMENTS
A. Palo Alto Municipal Code, Chapter 16.42: Seismic Hazards Identification Program
B. Seismic Risk Assessment Study. The study includes the following items.
a. Legislative Review Report
b. Local Program Best Practices Assessment
c. Building Inventory for Loss Estimate
d. Conceptual Seismic Retrofits and Cost Estimate
e. Loss Estimate of Existing Building Stock
f. Loss Estimate of Retrofitted Building Stock
g. Review of Past Retrofits
h. Additional Recommended Program Features
C. Threat and Hazard Identification and Risk Assessment (August 2014)
D. Policy and Services Committee Staff Report 5293, Discussion of Updating the Seismic
Safety Chapter of the Municipal Code for Hazardous Buildings (December 9, 2014)
E. Palo Alto Municipal Code, Chapter 18.18: Downtown Commercial (CD) District
F. Seismic Risk Management Program Advisory Group Members
G. Seismic Risk Management Program Advisory Group Summary Report on Process,
Discussions, and Outcomes (November 21, 2016)
H. Advisory Group Meeting Minutes, Presentations and Handouts (contained at the Seismic
Risk Management Advisory Group website at
<http://www.cityofpaloalto.org/gov/depts/ds/srmag.asp>
Attachments:
Attachments
Attachment_A_-_PAMC_16.42_Seismic_Hazards_ID_Prgm[1]
Attachment_B_-_Palo_Alto_Seismic_Risk_Assessment_Study_-_Final_Report_-
_2016_12_21[1]
Attachment_C_-_Palo_Alto_Threats_Hazards_Risk_Assessment_(August_2014.1)[1]
Attachment_D_-_Policy_and_Services_Staff_Report_5293[1]
Attachment_E_-_PAMC_18.18_CD_District[1]
Attachment_F_-
_Seismic_Risk_Management_Program_Advisory_Committee_Members_01.15.16[1]
Attachment_G_-
_Palo_Alto_Seismic_Risk_Mgt_Prog_AG_Summary_Rev_2016_11_21[1]
Attachment_H_-_SRMP_Advisory_Group_Agenda-Minutes-Presentations-Handouts[1]
Attachment E
Final Report
Seismic Risk Assessment Study
Palo Alto, California
21 December 2016
#2015-087S
Rutherford + Chekene
375 Beale Street, Suite 310
San Francisco, CA 94105
Attachment F
Palo Alto Seismic Risk Assessment Study December 21, 2016
Final Report Page i
TABLE OF CONTENTS
PALO ALTO SEISMIC RISK ASSSESSMENT STUDY
Section / Subsection
I. INTRODUCTION ............................................................................................................................................. 1
II. LEGISLATIVE REVIEW REPORT ....................................................................................................................... 5
1. Introduction ..................................................................................................................................... 7
2. Current California Seismic-Related Building Codes, Legislation, and Key Institutions .................... 7
3. Legislative Leadership and Recent Development .......................................................................... 18
4. Conclusions .................................................................................................................................... 20
5. References Cited ............................................................................................................................ 24
III. LOCAL PROGRAM BEST PRACTICES ASSESSMENT ...................................................................................... 25
1. Introduction ................................................................................................................................... 28
2. Analysis of Policy Features and Outcomes of local Seismic Risk Mitigation Programs ................. 30
3. Implications and Potential Policy Directions for Palo Alto ............................................................ 67
4. References and Resources ............................................................................................................. 77
IV. BUILDING INVENTORY FOR LOSS ESTIMATE ............................................................................................... 79
V. VULNERABLE BUILDING CATEGORIES ......................................................................................................... 85
VI. CONCEPTUAL SEISMIC RETROFITTING OF REPRESENTATIVE VULNERABLE BUILDINGS ............................. 87
VII. LOSS ESTIMATING FINDINGS FOR EXISTING BUILDING STOCK ................................................................... 91
VIII. LOSS ESTIMATING FINDINGS WITH BUILDINGS RETROFITTED ................................................................... 97
IX. REVIEW OF PAST SEISMIC RETROFITS ....................................................................................................... 101
X. ADDITIONAL RECOMMENDED PROGRAM FEATURES .............................................................................. 103
XI. QUESTIONS TO GUIDE COUNCIL DELIBERATIONS AND POTENTIAL ISSUES FOR FUTURE STUDY ............ 107
1. Questions to help guide council deliberations ............................................................................ 107
2. Potential issues for future study and consideration .................................................................... 108
Attachment F
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Final Report Page ii
APPENDICES:
Appendix A - Table of Historic California Earthquake Risk Reduction Legislation.
Appendix B - Table of Contemporary California Earthquake Risk Reduction Legislation.
Appendix C - Table Describing Incentives Used in Local Earthquake Risk Reduction Programs.
Appendix D - Options for Moving to a Comprehensive, Resilience Approach
Appendix E – Retrofit Concepts Designs for 12 Prototype Buildings
Appendix F – Retrofit Cost Estimates for 12 Prototype Buildings
Attachment F
Palo Alto Seismic Risk Assessment Study December 21, 2016
Final Report Page 1
CHAPTER I.
INTRODUCTION
In 1986, the City of Palo Alto was one of the first cities in California to establish a comprehensive
seismic mitigation program. It covers unreinforced masonry buildings, buildings built before 1935 with
over 100 occupants, and buildings built before August 1, 1976 with over 300 occupants. After 30 years,
75% of the 89 buildings included in the program have been demolished or retrofitted. The 2014 South
Napa Earthquake spurred the City to reevaluate its program. They engaged a team led by Rutherford +
Chekene (R+C) to perform a comprehensive assessment of the expected performance of the City’s
building stock in potential earthquakes, and started a community engagement effort to help identify
resiliency goals and associated mitigation policies and programs. The R+C project team includes Sharyl
Rabinovici, a public policy and community engagement specialist; Hope Seligson (initially with MMI
Engineering and now Seligson Consulting) for loss estimating; and Vanir Construction Management for
cost estimation of building replacement cost and retrofitting.
The technical assessment covered over 2,500 buildings (single family and two-family residences were
excluded) with a wide array of potentially vulnerable structural systems. The findings show that the
estimated losses to Palo Alto buildings and contents in a M7.9 scenario event will be significant, on the
order of $2.4 billion. Furthermore, this figure does not include business disruption, or ripple effects in
the local economy or real estate market, nor does it include the economic value of loss of life. Among
the categories of highest concern are pre-1977 “soft-story” wood frame, pre-1978 tilt-up concrete,
pre-1977 cast-in-place concrete construction, and pre-1998 steel moment frames. The technical
assessment revealed that the potential reduction in losses from retrofitting these buildings is over $1
billion in a M7.9 scenario event.
R+C’s scope included a series of tasks and associated task reports and presentations. These included
the following:
A survey of state and local seismic policies and best practices;
Development of a building inventory for Palo Alto using digital information and field surveys;
Assignment of costs to buildings and contents in the inventory;
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Description of vulnerable building categories, including five additional categories not covered
under the current ordinance;
Conceptual seismic retrofitting of representative vulnerable buildings;
Loss estimate findings in a major seismic event for the current condition and after retrofitting;
Review of past seismic retrofits; and
Discussion of additional recommended program features.
These task reports and presentation information have been compiled to form this Seismic Risk
Assessment Study. Each chapter in the study addresses one or more of the project task efforts.
Appendices provide additional details for selected tasks.
A Seismic Risk Management Advisory Group made up of community and industry stakeholders and City
staff was appointed and was also an essential component of the overall project. The Advisory Group
insured that local building experience and community priorities were considered as the study moved
forward. The group met six times with City staff and the R+C team over a period of nine months. The
Advisory Group was introduced to the findings regarding the community’s earthquake vulnerability,
impacts on vulnerable building types, as well as the ‘best practices’ used by other communities to
promote community wide welfare and to encourage seismic retrofit of various vulnerable buildings
types. The Advisory Group then discussed the assessment findings and formulated potential directions
for City of Palo Alto leaders to consider going forward in updating the City’s seismic mitigation
programs. At the end of the Advisory Group process, a summary memo, reviewed by all members of
the Group, was prepared to document their input to the study. The November 21, 2016 memo is
entitled “Seismic Risk Management Program Advisory Group Summary Report on Process, Discussions,
and Outcomes.”
The following table summarizes the outcome of the seismic risk assessment and includes the Advisory
Group discussions. The table is organized around eight vulnerable building categories or building types.
Categories I, II and III encompass the identified vulnerable buildings for the 1986 ordinance and are
primarily located in the downtown commercial district. Categories IV through VIII include additional
buildings at risk, as identified in the Seismic Risk Assessment Study. These buildings are located
throughout the city.
There was little to no support for maintaining the status quo within the Advisory Group. As shown in
the following table, the Advisory Group favored requiring property-owner prepared seismic evaluation
reports for all categories, except for Category VIII (other older nonductile concrete buildings). They
also favored mandatory retrofit for the remaining Category I unreinforced masonry buildings identified
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Final Report Page 3
in the 1986 ordinance that have not been seismically retrofitted or demolished. For the Category II
and III buildings in the current ordinance, retrofit should be required when a certain event or “trigger”
occurs such as when a substantial renovation occurs or the property is put up for sale. Among the new
vulnerable building types, the greatest concern was expressed for soft-story wood frame buildings and
older concrete tilt-up buildings. The Advisory Group thought that retrofit of these structures should be
either mandatory or triggered by substantial renovation or sale. The Advisory Group was concerned
about delay in the retrofit of these structures given the number of the vulnerable buildings, the
number of people who could be affected should the buildings be significantly damaged, and the
considerable cost to the community if the structures in these categories were lost because of an
earthquake. The Advisory Group considered a timeline of 2-4 years for the mandatory evaluation
report and 4-8 years to complete mandatory retrofit construction. The Advisory Group supported
increasing disclosure measures on building status through website listing and tenant notification. They
also suggested that the most beneficial financial and policy incentives to encourage compliance with
the new requirements would be fee waivers, expedited permitting, and property-assessed financing
tools.
Following the preparation of the Advisory Group summary, R+C assisted City staff in preparing a staff
memo for an upcoming City Council meeting. It includes more detailed recommendations to the
Council on proposed revisions to the City’s seismic hazard mitigation ordinance and recommends that
the Council provide direction to City staff on revising and expanding the City’s building code and
related ordinances.
Attachment F
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Final Report Page 4
Summary of Recommended Policy Directions from the Seismic Risk Management Program Advisory Group
Category Approx.
Number
Building
Type
Date of
Construction
Occupants Evaluation
Report
Voluntary,
Triggered, or
Mandatory
Retrofit1
Deadlines for Evaluation Report and
Retrofit Construction (years)2
Disclosure Potential Incentives
Current Program (Potential Revision in Italics)
I 10 Un-
reinforced
masonry
NA Over 6
(and over
1,900 sf)
Required Mandatory Report: Expired
Construction: 2-4
Website
listing and
tenant
notification
Fee waiver, expedited
permitting, FAR bonus/
transfer of development
rights (TDR) II 4 Any Before 1/1/35 Over 100 Required Voluntary or
Triggered
Report: Expired
Construction
• Voluntary: Not required
• Triggered: At sale or renovation
III 9 Any Before 8/1/76 Over 300 Required Voluntary or
Triggered
Expanded Program
IV 294 Soft-story
wood
frame
Before 1977 Any Required Triggered or
Mandatory
Report: 2-4
Construction
• Triggered: At sale or renovation
• Mandatory: 4-6
Same as
above
Fee waiver, expedited
permitting, TDR, parking
exemptions, permission to
add units
V 99 Tilt-up Before 1998 Any Required Triggered or
Mandatory
Report: 2-4
Construction
• Triggered: At sale or renovation
• Mandatory: 4-6
Same as
above
Same as Categories I, II and
III
VI 37 Soft-story
concrete
Before 1977 Any Required Voluntary,
Triggered or
Mandatory
Report: 2-4
Construction
• Voluntary: Not required
• Triggered: At sale or renovation
• Mandatory: 6-8
Same as
above
Same as Categories I, II and
III
VII 35 Steel
moment
frame
Before 1998 Any Required Voluntary,
Triggered or
Mandatory
VIII TBD Other older
nonductile
concrete
Before 1977 Any Not rec. at
this time
Not
recommended
at this time
Report: NA
Construction: NA
NA NA
1Voluntary: Retrofit is voluntary.
Triggered: Retrofit is triggered when the building is sold or undergoes substantial renovation.
Mandatory: Retrofit is required per a fixed timeline.
2Deadlines provide a potential range. Timelines would vary depending on tiers or priority groupings of different subcategories.
Attachment F
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CHAPTER II.
LEGISLATIVE REVIEW REPORT
Executive Summary
This chapter summarizes the seismic risk management policy context within the state of California to
support Palo Alto’s current effort to update its program. The report was prepared per Task 2 of the
Consulting Agreement between Rutherford + Chekene and the City of Palo Alto, dated August 17,
2015. The scope of Task 2 is to:
Review existing and pending State legislation related to soft-story buildings and other seismically
vulnerable buildings and provide a brief summary.
Provide a concise review of relevant and pending state legislation, with a summary that can be
presented at community and staff meetings or in reports to Council.
The process of creating this legislative review included searches of legislative data bases, search and
review of published and online reports and materials, several phone interviews with leaders in the
engineering profession as well as local and state government staff, and development of insights from
the consulting team based on their experiences in this arena.
High level findings include the following:
Palo Alto is affected by numerous relevant California existing laws and regulations dating from
the 1930s through the present. These laws regulate many aspects of Palo Alto’s built environment,
including certain classes of building uses such as hospitals, public schools, and essential facilities;
setting code minimums for new construction; and mandating land use planning and real estate
disclosure measures for natural hazards including earthquakes. Unreinforced masonry (URM) is at
present the only structural system type for which the state requires local jurisdictions to have a
program.
If it so chooses, Palo Alto has wide authority to expand or strengthen its approaches to seismic
mitigation. The power to do more about earthquake vulnerabilities is primarily in the hands of the
local jurisdictions that have significant discretion in the kinds of policies they can adopt.
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Palo Alto has many additional actions it can take to make sure it is complying and taking greatest
possible advantage of state level regulations and opportunities. In particular, opportunities exist
now to align a new seismic program with two ongoing mandated planning efforts the City is already
engaged in: Palo Alto’s General Plan and its Local Hazard Mitigation Plan.
Based on what state laws allow and in some cases recommend, many broad policy directions exist for
Palo Alto going forward in terms of updating its seismic mitigation program. For example, Palo Alto
could choose to:
(1) implement measures to increase the effectiveness of its current program, for instance by
offering additional or larger incentives or devoting more resources to program visibility and
implementation;
(2) expand the City’s current voluntary seismic mitigation programs to address additional
building types or uses;
(3) add mandatory screening or evaluation measures for one or more vulnerable building types
such as soft-story buildings or older concrete structures;
(4) upgrade the City’s current voluntary URM program to make retrofitting mandatory;
(5) create a program that mandates seismic retrofits for one or more additional (non-URM)
vulnerable building types;
(6) craft a program that combines any or all of the above measures. Local precedents for all
these types of approaches exist and are described and discussed in a separate Task 3 report; or,
(7) continue the status quo current program.
Although formally outside the scope of the current effort, Palo Alto also has additional opportunities
for strengthening and expanding its earthquake-related efforts in terms of land use planning, public
education and awareness, and small residential structures, such as:
(8) develop partnerships with the private and non-profit sectors to promote insurance take up
and business continuity planning; and,
(9) devote more resources to increasing awareness among its citizens about low cost or free
ways to become more aware and prepared for disasters more broadly.
Ultimately, the recommended policy directions and action steps for Palo Alto will be informed by
related efforts in this project to analyze the most current vulnerability information available, and later
determined through an inclusive decisionmaking process going forward.
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1. INTRODUCTION
This report surveys the public policy landscape in the state of California related to earthquake
mitigation and describes each policy or program’s relevance for Palo Alto and similar jurisdictions. The
scope is intentionally broad so that it can serve as a primer or look-up resource for persons with varied
levels of background knowledge about the topic. Section 2 organizes information about the reviewed
policies, programs, and institutions based on the type of policy or program. These range from building
codes and mitigation mandates to educational efforts and tax-based loan financing strategies.
Section 3 briefly provides information about current State level policy leadership and the small amount
of earthquake-related recent and proposed legislation. Section 4 presents options for Palo Alto
through a summary of the review’s findings. Appendices A and B to this report provide detailed tables
of current and pending or recent legislative proposals, respectively.
The process of creating this Legislative Review included searches of the California’s LegInfo database,1
search and review of published and online reports and materials, several phone interviews with state
and engineering profession leaders, and development of insights from the consulting team based on
their experiences in this arena. This review covered over 50 related individual existing laws or passed
referenda, in addition to the state’s Existing and Historic Building Code provisions.
2. CURRENT CALIFORNIA SEISMIC-RELATED BUILDING CODES, LEGISLATION, AND KEY INSTITUTIONS
This section presents legislation and programs in narrative format to address interrelationships among
these laws and to present broader implications for Palo Alto. Relevant laws and programs related to
Palo Alto’s obligations and opportunities regarding earthquake mitigation are categorized by type and
how each works. Specific laws referenced are shown in bold. The accompanying table in Appendix A
lists the identified relevant current state legislation organized by year established.
State laws related to seismic safety can be categorized as relating to building codes, targeting of
existing building types or uses, land use planning, real estate practice requirements, and financial
policies such as the tax code, insurance, and incentives.
1 http://www.leginfo.ca.gov (Accessed January 13, 2016).
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Building Codes
New construction in Palo Alto is governed by the California Building Code (CBC) that is updated every
three years. Updates are adopted by the City Council. The International Building Code (IBC) is the
underlying model code on which the provisions of the CBC are based. Legally, every local jurisdiction in
California is required to adopt the state building code and to enforce that code. Above and beyond the
minimums of the CBC, each jurisdiction has flexibility if justified by local climatic, geological (including
seismic), and topographical conditions. Several jurisdictions have done that as part of their seismic
mitigation programs, as detailed later and in Chapter III.
Standards for rehabilitation, renovation, repairs, retrofits, or additions to existing structures exist in
Chapter 34 of the CBC. The International Existing Building Code (IEBC) provides additional specific
methodologies that jurisdictions may decide to adopt in whole or in reference to particular sections.
The City of Palo Alto has its own Historic Building Inventory of hundreds of buildings as well as several
Historic Districts and both state and federally designated historic properties. Therefore, the State
Historical Building Code2 is also relevant, as administered by the Division of the State Architect (DSA)
under the Department of General Services. Officially designated historic structures are subject to
different rules for rehabilitation which are generally more flexible and permissive than those in
Chapter 34 of the CBC. Local jurisdictions can specify enhancements for seismic reasons as long as the
justifications and nature of such changes are fully public and documented on record with the State
Historical Building Safety Board.3 A detailed list of key provisions is given on the DSA website4.
Targeted Building Types
Unreinforced Masonry (URM)
Inventories of specific building types have formed the backbone of California seismic policy
towards existing buildings since at least the 1930s, but it was the 1986 Unreinforced Masonry
(URM) Law that firmly established the precedent of using inventories to promote retrofits of
existing seismically vulnerable buildings. Through this policy, in Section 8875 of the California
Government Code, the State Legislature required all 366 local governments in Seismic Zone 4
(the highest hazard level) to inventory their URM buildings, establish some kind of loss-
2 Health and Safety Code, Division 13, Part 2.7, §18950-18961.
3 “Each local agency may make changes or modifications in the requirements contained in the California Historical Building
Code, as described in Section 18944.7, as it determines are reasonably necessary because of local climatic, geological,
seismic, and topographical conditions. The local agency shall make an express finding that the modifications or changes are
needed, and the finding shall be available as a public record. A copy of the finding and change or modification shall be filed
with the State Historical Building Safety Board. No modification or change shall become effective or operative for any
purpose until the finding and modification or change has been filed with the board.” [Health and Safety Code §18959.f.]
4 http://www.dgs.ca.gov/dsa/AboutUs/shbsb/shbsb_health_safety.aspx (Accessed January 23, 2016).
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reduction or remediation program within four years, and report progress to the California
Seismic Safety Commission (CSSC).
Each county or municipality was allowed to design its own program. In general, three main
types of local programs were utilized: 1) mandatory retrofit, 2) voluntary retrofit, and 3) notice
to owners that the structure is a URM building. When retrofits were encouraged or required,
the local government set the standards to be met. Palo Alto already had an inventory and
program in place for URMs at the time the law was passed, and thus it was mainly subject to
the reporting requirements.
Mandatory signage was later required and is another controversial aspect of the State’s
approach to URM buildings. Section 8875.8 of the Government Code increased enforcement
efforts on the requirement for warning placards to be posted at the entrances to un-retrofitted
URM buildings. In 2006, URM building owners had posted 758 signs (see Figure 1 for required
text); almost all jurisdictions report the signage had no noticeable effects (CSSC, Status of the
Unreinforced Masonry Building Law, 2006).
Figure 1: URM sign example text.
Reviews of the URM Law by the CSSC have shown it to be a success over the long term. In 2006
(the last comprehensive state survey available), compliance with the policy was 93%, and over
70% of identified URM buildings have been either retrofitted or demolished (CSSC, Status of the
Unreinforced Masonry Building Law, 2006). More than half (52%) of affected jurisdictions
adopted a mandatory program, which has proven by far to be the most effective type. Eighty-
seven percent of identified properties have been retrofitted or demolished in jurisdictions with
mandatory programs, compared to thirteen to 25 percent in jurisdictions with other program
types.
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Some of the URM law’s influences are subtler. The state URM law is credited with creating
greater awareness among community leaders and increasing practical experience and capacity
to address seismic policy implementation in local jurisdictions. It set the precedent of
preserving “local choice” in how to address the problems of seismically-vulnerable existing
buildings. This law also brought some public attention to the issue, through exposure to
warning signs at building entrances. In jurisdictions with highly effective programs, the URM
law likely set the stage for greater willingness to adopt stronger, more proactive approaches for
other building types.
Targeted Building Uses
Hospitals
Palo Alto is host to at least two major hospitals, the Palo Alto Veteran’s Administration Hospital
and the Lucile Packard Children’s Hospital, as well as a number of urgent care clinics and other
health care facilities, for instance related to Stanford Hospital. State-mandated seismic
minimums and upgrade requirements for hospitals were put in place in 1973 through SB 1953
and periodically amended since. The Office of Statewide Health Planning & Development
(OSHPD) develops guidelines, administers the program, and oversees compliance.
Extraordinary resources have been spent to upgrade and develop new hospitals in response to
SB1953, resulting in major improvements to both seismic safety and in patient care (OSHPD,
2005). However, progress has been slower than hoped, in part because of the costs of achieving
the high levels of performance that the law demands but also because of program complexity
and organizational difficulties in managing upgrade programs. A comprehensive study of SB
1953 implementation showed that even organizational leaders highly motivated to reduce risk
in the context of strict mandates were not always able to achieve timely progress (Alesch,
2012).
Public Schools
Following the 1933 Long Beach quake that rendered over 230 Southern California schools
unsafe, the Field Act was passed to require higher seismic design minimums in new public
school construction. The 1939 Garrison Act required school districts to retrofit or replace pre-
Field Act schools. However, many schools did not comply until the mid-1970s.The Division of
the State Architect (DSA) oversees this program, and since 2002 has done tracking via the “AB
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300 List.” 5 Further detail about Field Act implementation statewide can be found in formal
state reports (See, e.g., CSSC, 2009).
The status of approximately six Palo Alto area schools that have buildings on the “AB 300 List,”
could be relevant to future policy development efforts depending on the extent to which the
city relies on schools in its emergency response plans. Functioning schools are also known to
play a large role in resumption of local business activity as part of recovery.
Essential Services Buildings
State law recognizes that buildings that house mission-critical jurisdictional services and
administrative functions should be safe and functional after a major local event. Palo Alto is
required by the California Essential Services Building Seismic Safety Act of 1986 to follow
enhanced regulations during the design, rehabilitation, and construction of essential service
facilities, defined as fire stations, police, California Highway Patrol, or sheriff offices, or any
buildings used in part or whole to conduct emergency communications and operations. As with
hospitals, the DSA develops and maintains the design and construction requirements and tracks
compliance for this law.
Land Use, Zoning, and Real Estate Disclosure Requirements
General Plan Requirements
According to the State Planning and Zoning Law, Palo Alto and other California jurisdictions
have been required since 1971 to address earthquake vulnerabilities in their General Plans,
currently in the Safety Element.6 The Governor’s Office of Planning and Research (OPR)
provides General Plan Guidelines for what jurisdictions must do in creating and implementing
their plans, mostly recently in 2011.7 Typical earthquake-related provisions focus on avoiding
development in hazardous areas (for instance near known faults) and adoption of zoning and
use requirements that can reduce hazards (such as creation of retention and recharge basins to
lessen the impacts of storms).
Palo Alto’s last General Plan was adopted over ten years ago. Since 2008, staff have been
reviewing and updating different elements in turn. An analysis should be undertaken of any
relevant earthquake hazard-related aspects in it, and care should be taken to align and
integrate future mitigation program efforts with the City’s updated General Plan, which is
5 http://www.documents.dgs.ca.gov/dsa/ab300/AB_300_List.pdf (Accessed January 23, 2016). List described as up to date
as of Thursday, September 10, 2015.
6 Government Code §65300-65303.4.
7 https://www.opr.ca.gov/docs/complete_pzd_2011.pdf (Accessed, March 6, 2016).
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currently in development. As of 2016, Palo Alto is working on a comprehensive update to be in
effect through 2020 to 2030. More detail is available on a city website designed specifically as
part of a highly engaged community involvement process.8
Zoning
Palo Alto is on the list of California cities that contain some areas designated by the state as an
“Earthquake Fault Zone” (Hart, 2010). The California Geological Survey (CGS) under the
California Department of Conservation (DOC) oversees implementation of the Alquist-Priolo
Earthquake Fault Zoning Act of 1972, a particularly important legacy policy in understanding
California earthquake risk management policy. The CGS regularly conducts and updates studies
that identify active faults. Buildings within an “Earthquake Fault Zone” face additional planning,
use, and disclosure obligations. Additionally, the 1990 Hazards Mapping Act gave DOC
responsibility for mapping areas prone to liquefaction, earthquake-induced landslides, and
amplified ground shaking. Within these mapped Zones of Required Investigation, geotechnical
investigations to identify hazards and formulate mitigation measures are required before
permitting most development.
Small Residential Real Estate Mandates and Disclosures
All sellers of real property in Palo Alto are required to disclose certain facts about the building
location and its condition related to earthquake hazards. These requirements began with the
Natural Hazards Disclosure Act of 1990, which has detailed provisions for what sellers of real
property are obligated to do and what kinds of information they must provide prior to point of
sale. Requirements are more extensive when the property being sold lies within one or more of
the state-mapped hazard areas, including landslides, liquefaction, and Earthquake Fault
Zones.”9
Since 1993, all sellers of residential properties of four units or less must under Government
Code Section 8897.1-8897.5:
o Inform the buyer about known home weaknesses related to earthquake risk;
o Properly strap the water heater;
o If the home was built before 1960, deliver a copy to the buyer of the Homeowner’s
Guide to Earthquake Safety10 brochure produced by the CSSC (The real estate agent is
holds responsibility for this requirement being met);
8 http://www.paloaltocompplan.org/ (Accessed January 23, 2016).
9 http://www.conservation.ca.gov/cgs/rghm/ap/Pages/disclose.aspx (Accessed January 20, 2016).
10 Available at: http://www.seismic.ca.gov/pub/CSSC_2005_HOGreduced.pdf (Accessed February 1, 2016).
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o Deliver to buyers a Natural Hazards Disclosure Form telling buyers whether the home is
in an Earthquake Fault Zone or in a Seismic Hazard Zone; and,
o Complete and deliver to buyers a Residential Earthquake Hazards Report.
A similar document called the Commercial Property Owners Guide to Earthquake Safety11
makes recommendations for commercial property buyers and sellers at the time of sale. The
only requirement is that sellers must deliver a copy of the booklet to a buyer, “as soon as
practicable before the transfer,” (Government Code, Section 8893.2) if the property was built
before 1975 and has precast (tilt-up) concrete or reinforced masonry walls and wood-frame
floors or roofs.
Palo Alto currently features links to both the aforementioned guides on its Building Department
website.
Legal Obligations to Tenants
California case law in Green v. Superior Court (1974, 10 Cal.3d 616) established that a rental unit
must be “fit to live in,” or “habitable.” In legal terms, “habitable” means that the rental unit is
appropriate for occupation by human beings and that it substantially complies with state and
local building and health codes that materially affect tenants’ health and safety (CA Civil Code
§1941, 1941.1).
At time of writing, no common law precedents could be identified regarding thresholds related
to seismic risk that would be actionable for tenants to reasonably claim breach of a landlord’s
implied warranty of habitability. California law is broad by stating that “other conditions may
make a rented property not habitable” (CA Civil Code §1941, 1941.1). For example, a rented
property may not be habitable if it does not substantially comply with building and housing
code standards that materially affect tenants' health and safety (CDCA, 2012). This could be a
lead or mold hazard, sanitation issues, or an endangering nuisance, but also potentially if the
building is substandard because of a structural hazard.
In seeking to develop any new programs, Palo Alto should consider conducting a legal analysis
of this important but untested aspect of seismic mitigation policy. Some housing and tenant
rights groups have asserted that soft-story and other generally accepted seismic vulnerabilities
may constitute a deficiency that a landlord has an obligation to repair, regardless of whether
the local jurisdiction has required such work. Citizen complaints of this nature surfaced in
Berkeley for instance in 2008 to 2010 (personal communication, 2010 with Jay Kelekian, City of
Berkeley Rent Stabilization Board President).
11 Available at: http://www.seismic.ca.gov/pub/CSSC_2006-02_COG.pdf (Accessed February 1, 2016).
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Special Earthquake-Related State-Level Entities and Programs
Following are a few more important state-level entities and resources of which Palo Alto can take
advantage.
California Seismic Safety Commission (CSSC)
The California Seismic Safety Commission (CSSC), established in 1975, advises the Governor,
Legislature, and state and local governments on aspects of earthquake vulnerability and policy.
Its staff offer technical assistance to cities in developing and carrying out seismic related
programs. The CSSC is responsible for maintaining a five-year California Earthquake Loss
Reduction Plan to establish strategy and coordination for state and local government actions to
mitigate earthquake hazards. The most recent statewide Loss Reduction Plan was published in
2013 (CSSC, 2013). It contains detailed lists of policy issues and recommendations that, while
comprehensive, prioritized, and sensible, have had limited traction owing to lack of elected
official leadership and budget. Other duties include tracking progress on the state URM law and
deriving policy lessons from earthquake events. Several CSSC publications are among the best
resources for evaluating local mitigation programs.
California Earthquake Authority (CEA)
The California Earthquake Authority (CEA) is a privately-funded, publically managed non-profit
entity that provides private insurance policies to homeowners and renters. Eligibility includes
homes of four units or less through participating insurers. The earthquake insurance take-up
rate statewide is around ten percent. As of January 2016, CEA-affiliated underwriters can now
offer a premium discount up to 20% for mitigation investments made. The number of small
residential buildings in Palo Alto whose owners carry earthquake insurance is not known, but
those that do or that purchase it from hereon could be eligible for this discount. Palo Alto
could potentially work to make sure this benefit is better advertised and utilized by building
owners.
Additionally, a substantial portion of CEA’s annual premium intake is legislatively required to be
spent on efforts to achieve mitigation in one-to-four unit homes throughout the state. These
funds have been invested in research as well as an important new mitigation grant program for
small residential houses called Earthquake Brace and Bolt, which is further described in the
Financial Incentives section on the California Residential Mitigation Program. Currently,
enrollment for cities is closed but expansion is planned in the future.
Governor’s Office of Emergency Services
Formerly known as the California Emergency Management Agency, the Governor’s Office of
Emergency Services (Cal-OES) coordinates statewide emergency preparedness and response
activities. Palo Alto might have untapped opportunities to train City employees at CAL-OES’s
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Specialized Training Institute.12 For instance, they have an “Essential Emergency Services
Concepts – Earthquakes.”
Financial Provisions, Tax Code, and Other Incentive Policies
The potential difficulty of affording retrofit work is universally recognized as a barrier for public and
private owners alike. A variety of reports have attempted to catalog incentive, financing and in-kind
assistance options that are relevant to city earthquake and resilience programs (See e.g., ABAG, 1992;
ATC, 2010; ABAG, 2014; MMC, 2015).
This section highlights a few key pieces of enabling state legislation and federal tax programs that
jurisdictions such as Palo Alto could utilize. Specific examples of how different jurisdictions have used
specific financing and incentive programs are analyzed in the Task 3 Report.
General Obligation, Special District, and Mello-Roos District Bonds
Palo Alto is allowed to take on general obligation bond debt to help pay for retrofit or
construction of new public buildings and to generate funds for providing loans to private
owners for seismic work if doing so constitutes a compelling public purpose (Government Code
§43600-43638; Government Code §29900-29930).
Advocates have also speculated that communities might be able to use the Mello-Roos
Community Facilities Act of 1982 (Government Code §53311-53317.5). This act allows localities
in California to create special Capital Facilities Districts that can sell bonds to generate funds for
infrastructure and community facilities and then levy additional property taxes on the real
property owners in that district. Such taxes are not subject to Proposition 13 restrictions on
property tax increases. Covered services may include streets, water, sewage and drainage,
electricity, infrastructure, schools, parks and police protection in old or newly developing areas.
The tax paid is used to make the payments of principal and interest on the bonds.
Historic Property Tax Reductions
Palo Alto has many historic structures and may be able to take advantage of the Mills Act of
1972,13 which gives local governments the authority to enter into contracts with owners who
restore and maintain historic properties. In exchange, the property owners could get significant
property tax savings. Although cumbersome, St. Helena, California is one example of a city that
used this tool to help owners of unreinforced masonry buildings to seismically retrofit (ABAG,
unpublished soft-story report, 2015).
12 See: http://www.caloes.ca.gov/cal-oes-divisions/california-specialized-training-institute (Accessed February 1, 2016).
13 California Government Code, Article 12, §50280-50290, California Revenue and Taxation Code, article 1.9, §439-439.4.
Further information available at: http://www.ohp.parks.ca.gov/?page_id=21412 (Accessed February 1, 2016).
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Limits on Increases on Property Tax for Seismic Retrofit Costs
Existing state tax law (California Revenue and Taxation Code §74.5) provides that the cost of
an earthquake retrofit should not increase the property assessment used to determine the
amount of property taxes. The extent to which building owners take advantage of this benefit is
unknown and might be low because of requirements to submit specific information to their
County Assessor’s Office prior to conducting retrofit work. Many Assessors’ Offices do not have
forms for this purpose and their staff is not trained to process this benefit. At this time, it is not
known how Santa Clara County manages this issue. Palo Alto could potentially work to make
sure this benefit is better advertised and truly available to building owners.
Property Assessed Clean Energy (PACE) Financing
New financing programs are starting to exist that could help owners in Palo Alto who might
have difficulty securing financing on their own for a seismic retrofit. Based on the Property
Assessed Clean Energy (PACE) model first pioneered for solar improvements, owners can apply
for 100 percent financing for seismic retrofit work at competitive fixed rates over the useful life
of the improvements, to be repaid over up to 20 years with an assessment added to the
property’s tax bill. The levy stays with the building upon sale and costs can be shared with
tenants. Both Berkeley and San Francisco are participating in the open access AllianceNRG
Program14 that offer residential property owners this financing solution primarily for
sustainability upgrades and seismic strengthening projects for soft-story construction are also
eligible. The AllianceNRG program is offered through California’s Statewide Community
Development Authority (CSCDA) and partnerships with additional communities are now being
offered state-wide since 2015.
After the concept was launched in Berkeley in 2008, PACE programs stalled in 2010 the
country's two biggest home lenders, Fannie Mae and Freddie Mac, decided not to
underwrite mortgages for PACE customers because it added too much risk in the event of
a default because the PACE loan took precedence over the mortgage. Anecdotally,
jurisdictions have had some difficulties implementing this type of program for energy
improvements.15 Challenges include setting up this complex financing instrument which has
heavy involvement of third parties, barriers to owners that want to refinance, and barriers to
the transfer of a PACE-financed properties to a new owner.
14 https://www.alliancenrg.com/retail/ (Accessed January 20, 2016).
15 See e.g., http://www.voiceofsandiego.org/topics/science-environment/some-homeowners-looking-to-move-must-deal-
with-a-change-of-pace/ (Accessed February 2, 2016.
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California Residential Mitigation Program (CRMP)
Palo Alto and other cities can benefit if the citizens can stay in their homes and “shelter in
place” following a major local quake. One new important effort on this front is the California
Residential Mitigation Program (CRMP). It was formed in August 2011 to carry out mitigation
programs to assist California homeowners who wish to seismically retrofit their houses. CRMP’s
goal is to provide grants and other types of assistance and incentives for these mitigation
efforts. The California Residential Mitigation Program is a joint-exercise-of-powers entity (JPA)
formed by two core members: the California Earthquake Authority (a public instrumentality of
the State of California known as CEA) and the Governor’s Office of Emergency Services (Cal-
OES). CRMP is a legally separate entity from its members.
The first of these programs, Earthquake Brace + Bolt: Funds to Strengthen Your Foundation
(EBB)16 was launched as a pilot project in September 2013 in selected zip codes only. EBB offers
a cash grant up of to $3,000 for qualifying bolts or sill anchoring installment. Homeowners must
register and be accepted into the program, with a cap on the number of participants. The
current registration window was open from January 20 to February 20, 2016. Participation is
determined by lottery if more applications are received than funds are available. At present, no
Palo Alto zip codes are in the program. The selection of the specific neighborhoods and zip
codes was based upon analysis of U.S. Census data identifying areas of high seismicity and
having a concentration of owner-occupied homes built in 1979 or earlier. According to personal
communications with CEA mitigation program representatives, Palo Alto zip codes are not likely
to be prioritized highly owing to the modest number of very old single family homes.
Federally Mandated Municipal Obligations and Opportunities
Even though the focus of this review is California, two particularly relevant federal programs for Palo
Alto are described below. As with the state, no centralized governmental authority exists at the federal
level to regulate issues of seismic safety. Instead, authorities and strategies are widely distributed
among agencies at the local, state, and federal levels. For instance, the Department of Housing and
Urban Development operates several initiatives related to safer homes and resilient communities,17
and the General Services Administration must confront seismic risk concerns as it manages most
federal facilities. The federal role is concentrated in FEMA and principally focused on emergency
response and recovery, although mitigation is also addressed.
16 https://www.earthquakebracebolt.com/ (Accessed January 23, 2016)
17 See, e.g., the Smart Growth America Resilience States program, http://www.smartgrowthamerica.org/resilience/
(Accessed February 1, 2016).
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Local Hazard Mitigation Planning Under the Disaster Management Act
The federal Disaster Management Act of 2000 (DMA) and subsequent amendments specify
that local jurisdictions and states must have approved Hazard Mitigation Plans in place in order
to be eligible for aid following Stafford Act Disaster declarations and a variety of other benefits.
The State of California Multi-Hazard Mitigation Plan of 201318 is a comprehensive source of
information about state level requirements, mitigation strategies, as well as local and state
progress and opportunities for coordination (CSSC, 2013b).
Palo Alto current complies with the DMA through its participation in the 2011 Santa Clara
County’s Office of Emergency Services Annex to a 2010 region-wide “umbrella” Local Hazard
Mitigation Plan (LHMP) created by the Association of Bay Area Governments (ABAG). To create
the plan, representatives from County departments, private sector businesses, stakeholders,
and thirteen of the fifteen incorporated cities in Santa Clara County collaborated in identifying
and prioritizing potential and existing hazards. Mitigation objectives were identified and
prioritized and specific action steps are listed, many of which have been taken. Palo Alto is
currently preparing its contributions for updates to the Santa Clara County LHMP which must
be completed, submitted to the state, and approved by June 2017. The LHMP process creates
an opportunity to build synergies between an updated seismic program and other mitigation
efforts city and county-wide.
Federal Emergency Management Agency (FEMA) Pre-Disaster Mitigation Grants
Cities such as Palo Alto are eligible to apply to the Pre-Disaster Mitigation (PDM) Grant
Program19, created by Section 203 of the federal Robert T. Stafford Disaster Relief and
Emergency Assistance Act, funded annually by Congressional appropriation. The program aims
to assist States, territories, Federally-recognized tribes, and local communities in implementing
a sustained pre-disaster natural hazard mitigation program. Cities must submit a detailed
application during an open window to an annual competition. This program awards planning
and project grants as well as providing assistance in raising public awareness about reducing
future losses before disaster strikes. The program works on a 75%/25% cost share between
FEMA and the local jurisdiction, respectively, with a maximum grant of $3 million. Cities can
submit applications for multiple projects. Palo Alto could apply for support for future projects
ranging from updating city owned structures, direct financing or grants to a private class of
buildings or specific important structure.
18Available at: http://hazardmitigation.calema.ca.gov/docs/SHMP_Final_2013.pdf (Accessed February 1, 2016).
19 http://www.fema.gov/hazard-mitigation-grant-program (Accessed January 15, 2016).
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The disaster occurrence that opens a funding availability window does not necessarily have to
affect Palo Alto directly. For instance, any California jurisdiction with an active LHMP was
permitted to propose projects based on the Presidential Disaster Declaration for the 2015
Valley and Butte fires.
Finally, if City of Palo Alto employees have not already taken advantage of it, training
opportunities are available at the FEMA Emergency Management Institute in Maryland.20
3. LEGISLATIVE LEADERSHIP AND RECENT DEVELOPMENTS
Palo Alto citizens are represented in the state Senate by Jerry Hill (D) and in the Assembly by Rich
Gordon (D), 24th District, both with terms ending in 2016. High earthquake exposure throughout
coastal California has led legislators from a variety of districts to author legislative proposals. Most
recently, leadership has come from elected officials Nazarian, Chiu, and Monning.
Several different committees in the California Assembly and Senate have jurisdiction over issues
related to seismic safety and mitigation, building codes, and earthquake-related programs. In the
Assembly, the Committee on Housing and Community Development has jurisdiction over building
standards, common interest developments, eminent domain, farm worker housing, homeless
programs, housing discrimination, housing finance (including redevelopment), housing, natural disaster
assistance and preparedness, land use planning, mobile homes/manufactured housing, and rent
control. The Assembly Committee on Local Government has authority over a range of General Plan,
city finance, and housing policies. The most relevant Senate committee is Transportation and Housing,
which governs issues such as transfer of ownership, financing districts, manufactured housing, building
codes and standards, and common interest developments.
Through these committees, legislators have considered several pieces of legislation related to
earthquake mitigation in recent years. This review identified around ten such pieces of legislation
debated in the 2013 to 2015 California legislative sessions, including passed, pending, vetoed or never
fully heard bills (see Appendix B). Three key legislative proposals of interest to Palo Alto are briefly
described here.
Vetoed: Seismic Mitigation Tax Credits
In the most recent session, Assembly Member Adrin Nazarian (District 46 in the San Fernando
Valley) has sponsored legislation to create a state-wide seismic mitigation tax credit. The 2015
version AB 428 passed the legislature but was vetoed by the Governor based on funding
availability, lack of technical and administrative capacity in the Franchise Tax Board, and the
20 https://training.fema.gov/emi.aspx (Accessed February 1, 2016).
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program’s potential complexity. The law would create a first-come first serve state tax credit
equal to 30 percent of a “qualified taxpayer’s” “qualified costs” incurred for “seismic retrofit
construction.”
Pending: Permissions to Expand CEA Insurance Mitigation Discounts
CEA was active in promoting legislation last year to empower the CRMP to offer grants for small
residential retrofit work. Currently pending are AB 1429 (Chiu) and AB 1440 (Nazarian) that will
provide $3 million dollars to the CRMP for expanding its current EBB program.
Dead: Soft-Story and Older Concrete Mitigation Program Authorization
AB 2181 (Bloom)21 would authorize each city, city and county, or county to require that owners
assess the earthquake hazard of soft story residential buildings and older concrete residential
buildings. It includes older concrete residential buildings constructed prior to the adoption of
building codes that ensure ductility, and to initiates programs to inform owners, residents and
the public about such dangers. There is no state law that forbids such programs, but this law if
passed would remove any ambiguity that such programs are permitted and further justify local
actions to that effect.
4. CONCLUSIONS
Palo Alto is affected by numerous California laws and regulations related to seismically vulnerable
structures, dating from the 1930s to the present day. The requirements relate to many aspect of the
city’s built environment, including:
Code minimums for new construction;
Standards for seismic rehabilitation, including special provisions for historic properties;
Special programs and expectations for certain classes of use such as hospitals and public
schools, and essential facilities;
Mandatory and voluntary unreinforced masonry programs;
Mandated zoning and land use planning requirements that restrict use and add
requirements;
Grant and insurance programs available to one to four unit dwellings;
Financing authorities such as issuance of general obligation bonds and provisions for
handling of property taxes for the costs of needed seismic retrofit; and
21 http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201320140AB2181 (Accessed February 1, 2016.
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Real estate disclosure requirements.
Beyond some recent and pending efforts related to funding small residential mitigation grant programs
and Earthquake Early Warning, there is no apparent momentum at this time for new statewide
initiatives. That being said, Palo Alto can take any of several actions listed below to make sure it is
complying with and taking the greatest possible advantage of existing state laws and programs. For
example:
Palo Alto could confirm that all its URM buildings maintain the required signage.
Palo Alto could investigate the status of the approximately six Palo Alto area schools that
have buildings on the State’s “AB 300 List” related to the Garrison Act.
Palo Alto could identify and review the status of public facilities covered under the Essential
Services Building Seismic Safety Act and review its policies for guiding future planning for or
rehabilitation of such structures.
Palo Alto could take advantage of the current update process for its Local Hazard Mitigation
Plan to develop a strong, coherent, shared vision for how the city is going to address
earthquake risk, and encourage jurisdictions and special districts nearby to do the same.
Resources from FEMA Hazard Mitigation Grants and knowledgeable partners such as the
Association of Bay Area Governments may be available to assist in this effort.
Palo Alto could work carefully to incorporate the most up-to-date assessment of local
earthquake vulnerabilities as it revises the Safety Element of its General Plan.
Palo Alto could make sure its employees have taken advantage of the best available state and
federal emergency management training programs that are relevant to earthquake disasters
and recovery.
Palo Alto could develop partnerships and devote resources to more fully realizing the benefits
of statewide offerings of tax relief and requirements regarding real estate disclosure in
private sales. These policies aim to empower buyers and sellers to be better informed and able
to make better mitigation decisions for themselves but may be carried out incorrectly and are
under-enforced. Palo Alto could, for instance, work to make sure building owners apply for
relief from any property assessment increases that would otherwise result from investing in an
earthquake retrofit.
Palo Alto could seek closer ties to the California Earthquake Authority to help in promoting
mitigation and insurance coverage for one to four unit homes. CEA has recently been one of
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the lead entities in offering policy ideas and grant funding for earthquake mitigation of small
residential structures.
Palo Alto could evaluate whether it contains any vulnerable historic properties that might be
eligible for tax credits under the Mills Act. This Act provides the most significant direct source
of financial support from the state for local seismic retrofitting.
Palo Alto could investigate the issue of seismic habilitability minimums for suspected
earthquake vulnerable buildings. Legal uncertainty exists about whether tenants are already
entitled under current state law to request that their landlord upgrade a structure for being
“substandard.”
Palo Alto could join with fellow jurisdictions in advocating for changes in state law to
promote seismic mitigation.
Palo Alto could develop partnerships and devote resources to bringing more awareness
among its citizens about low cost or free ways to become more aware and prepared for
disasters more broadly. Cal-OES and many other state and non-profit institutions offer free
online tools such as http://myhazards.caloes.ca.gov/ to help citizens understand their risks and
take private action.
The power to address unmet seismic safety and recovery concerns clearly rests in the hands of cities,
counties, and special districts. If it so chooses, Palo Alto has legal authority to widen and/or strengthen
its structural mitigation program. Based on what state laws allow and in some cases recommends, this
review revealed the following non-exhaustive list of policy directions Palo Alto could pursue going
forward:
1. Palo Alto could implement measures to energize and raise the effectiveness of its current
program (outlined in City of Palo Alto Municipal Code 16.40), for instance by offering
additional or larger incentives or devoting more resources to program visibility and
implementation. Making the current program more effective would likely require additional
funding sources. Other jurisdictions are experimenting with some success in using tools such as
the new state-wide PACE financing program. Palo Alto could investigate opportunities to
establish special Mello-Roos or Mills Act districts to help finance local seismic mitigation.
2. Palo Alto could expand its voluntary seismic mitigation program to address one or more
combinations of additional building types, occupancy levels, or uses. The State Legislature has
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formally passed advisory legislation that encourages jurisdictions to adopt policies for building
types like soft-story and older concrete.22
3. Palo Alto could create mandatory screening or evaluation measures for one or more
vulnerable building types such as soft-story buildings or older concrete structures. Local
precedents for these approaches exist and are described and discussed in a separate Task 3
report.
4. Palo Alto could make its current voluntary URM program mandatory. Mandatory URM
programs in the State have been on average three times more effective than voluntary ones.
5. Palo Alto could create a program that mandates seismic retrofits for one or more additional
(non-URM) vulnerable building types. The State Legislature has formally passed legislation that
authorizes cities to adopt rehabilitation requirements for such programs This is important
because cities must reference acceptable standards that state clearly how owners can comply
with the requirement to retrofit.
6. Palo Alto could craft a program that combines any or all of the above measures. The Task 3
report shows that most leading local earthquake programs involve a customized mixture of
goals, requirements, and features.
7. Palo Alto could continue the status quo current program. Nothing under current state law
requires Palo Alto to change its current approach.
The City of Palo Alto is currently gathering up to date earthquake risk information about its building
stock and engaging its citizens and local experts in order to develop and evaluate specific policy
alternatives. The ultimate goal is to recommend to city leaders the best possible policy directions for
Palo Alto moving forward.
22 Health and Safety Code §19160-19168 http://www.leginfo.ca.gov/cgi-bin/displaycode?section=hsc&group=19001-
20000&file=19160-19168
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5. REFERENCES CITED
ABAG. (1992). Seismic Safety Incentive Programs: A Handbook for City Governments. Association of Bay Area
Governments, Oakland.
ABAG. (2014). Soft-Story Housing Improvement Plan for the Cit of Oakland. Oakland. Retrieved from
http://resilience.abag.ca.gov/wp-content/documents/OaklandSoftStoryReport_102914.pdf
Alesch, D. J. (2012). Natural Hazard Mitigation Policy: Implementation, Organizational Choice, and Contextual
Dynamics. New York, NY: Springer Business Science.
ATC. (2010). Here Today—Here Tomorrow: The Road to Earthquake Resilience in San Francisco. Community
Action Plan for Seismic Safety, Redwood City. Retrieved from
http://sfgov.org/esip/sites/default/files/FileCenter/Documents/9757-atc522.pdf
CDCA. (2012). California Tenants: A Guide to Residential Tenants’ and Landlords’ Rights and Responsibilities.
Retrieved January 16, 2016, from http://www.dca.ca.gov/publications/landlordbook/catenant.pdf
CSSC. (2006). Status of the Unreinforced Masonry Building Law. California Seismic Safety Commission,
Sacramento.
CSSC. (2009). The Field Act and its Relative Effectiveness in Reducing Earthquake Damage in Public Schools
Appendices. California Seismic Safety Commission, Sacramento.
CSSC. (2013). California Earthquake Loss Reduction Plan / Pre-Earthquake Economic Recovery. California Seismic
Safety Commission, Sacramento.
CSSC. (2013). California Enhanced State Multi-Hazard Mitigation Plan. Sacramento: California Seismic Safety
Commission.
Hart, W. A. (2010). Special Publication 42 (Fault-Rupture Hazard Zones in California)y. Retrieved from
http://www.conservation.ca.gov/cgs/rghm/ap/Pages/affected.aspx
MMC. (2015). Developing Pre-Disaster Resilience based on Public and Private Incentivization. National Institute
of Building Sciences, Multihazard Mitigation Council of the Center on Fire, Insurance, and Real Estate.
OSHPD. (2005). California's Hospital Seismic Safety Law: History, Implementation and Progress. Sacramento.
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CHAPTER III
LOCAL PROGRAM BEST PRACTICES ASSESSMENT
Executive Summary
This chapter summarizes the status of local seismic safety and mitigation programs in California
with the purpose of informing Palo Alto’s effort to update its own approach. It has been
prepared per Task 3 of the Consulting Agreement between Rutherford + Chekene and the City
of Palo Alto. The content builds on the state-level policy review presented in Chapter II. The
scope of Task 3 is to:
Review present best practices among jurisdictions and agencies in this area that require
seismic retrofitting and provide incentives, and deliver a brief summary.
Provide a concise and practical written summary of what other jurisdictions and counties
have done legislatively and programmatically to increase awareness about, assess, and
motivate mitigation of seismically vulnerable buildings, both listing and helpfully classifying
various approaches that have been used.
The process of creating this review included search and review of published and online reports
and materials, several phone interviews with community leaders as well as local and state
government staff, and development of insights from the consulting team based on their
experiences in this arena.
Palo Alto is currently laying a solid foundation for future program development by investing in
new inventory and risk information as well as community outreach and internal staff
discussions. In doing so, it is joining a group of leading coastal California coastal jurisdictions
such as Berkeley, Oakland, San Francisco, and Los Angeles that have recently stepped up their
earthquake risk reduction efforts. While there is much learning and information sharing going
on, each jurisdiction has developed their own customized policy package, and there is no single
best model that Palo Alto can straightforwardly adopt. Existing local approaches differ widely in
the following ways:
Policy mechanisms used to achieve progress;
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Scope of targeted building types or uses addressed;
Prioritization and compliance timeframes; and
Types of incentives offered.
Policy mechanisms in use range all the way from inventory only to mandatory retrofit with
timeframes under five years. In between are more gradual approaches such as voluntary
retrofit advocacy, incentives, provisions that make building deficiencies more visible to the
public (disclosure measures), and mandatory screening and evaluation requirements. An
important policy decision is whether any mandated actions are implemented on a fixed
timeline or triggered at sale or at some renovation cost threshold.
Targeted building types and characteristics also vary. The most commonly addressed building
type is unreinforced masonry (URM) construction due to state law SB 547, as discussed in the
Task 2 report. Over half of URM programs in the state require mandatory retrofit, often but not
always with a time frame on the order of ten to twenty years. By 2006, seventy percent of all
identified URMs were either demolished or retrofit. Retrofit rates are on average three times
higher in jurisdictions with mandatory retrofit compared to voluntary programs. Jurisdictions
used a wide variety of both financial and policy incentives to assist URM owners. Some
voluntary URM programs, including Palo Alto’s, coupled with incentives, have achieved similar
rates of success to mandatory programs.
Newer programs have focused on soft-story wood frame buildings, including ten Bay Area
jurisdictions and most recently Los Angeles as of 2015. Soft-story wood frame building
programs also range in requirements from notification only to mandatory retrofit, but several
jurisdictions have innovatively used intermediate mandatory screening and evaluation phases
to further assess risk exposure and determine the final set of buildings that will be affected by
retrofit requirements. Soft-story wood frame programs have largely been supported in the local
community. Even voluntary soft-story wood frame programs can be effective at motivating
retrofit action; one fourth of the soft-story wood frame buildings in the City of Berkeley were
voluntarily retrofit within a few years after a mandatory evaluation ordinance was
implemented. Compliance timeframes in soft-story wood frame programs tend to be short, on
the order of two to seven years.
A comparatively small number of southern California jurisdictions have acted to address older
concrete buildings, including Los Angeles, Burbank, Santa Monica, and Long Beach. Nonductile
concrete frame and tilt-up concrete structures in particular are known to pose serious risks.
Programs aimed at older concrete range from voluntary guidelines to mandatory evaluation
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and full retrofit requirements. Timeframes here vary greatly, from years to decades.
Information about the implementation and outcomes of these few programs is very limited.
Coming out of this local program review, alternative policy approaches for Palo Alto’s
consideration include:
Option 1: Status Quo. In this option, the existing ordinance with its mandatory evaluation,
voluntary retrofit approach remains in place without changes. Floor area ratio bonuses are
(were) available and could continue to be offered.
Option 2: Increase Scope, but Retrofit Remains Voluntary. Additional categories of structures
are added to the mandatory evaluation requirements. These could include any or all of the
building types discussed above, potentially also using additional location, use, or occupancy
criteria.
Option 3: Similar to Option 2, but Additional Disclosure Measures are Incorporated. This
option would be similar to Option 2, but with increased use of disclosure measures such as
prominently posting the building list on the City website, notifying tenants, requiring signage,
and/or recording notice on the property title.
Option 4: Increase Scope, Some Categories are Voluntary and a Few Categories are
Mandatory, with Enforcement by Trigger Threshold
This option builds on Option 3, but retrofitting would be required for some building types at
whenever future time a building is sold or undergoes substantial renovation above a set
threshold.
Option 5: Increase Scope, Some Categories are Voluntary and a Few Categories are
Mandatory, with Enforcement by a Fixed Timeline
This option would be similar to Option 4, but retrofitting is required according to a fixed
timeline. Timelines and enforcement emphasis could vary depending on tiers or priority
groupings to motivate prompt action for the most vulnerable or socially important structures.
Option 6: Increase Scope, but More Categories are Mandatory
This alternative is similar to Option 5, but retrofitting would be required for additional
categories on a fixed timeline. Palo Alto can also make its programs more stringent over time.
Explicit phasing has been successful in jurisdictions like Berkeley and San Francisco for
generating political consensus and enhancing administrative feasibility.
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Other program features and implementation factors should be considered in designing a future
program. Palo Alto will need to decide whether location, occupancy type, and/or number of
occupants should be included in the scope or just the timeline categories. Whether and which
incentives to offer is an important issue from a political and economic feasibility perspective,
one that affected community members will want to see inclusively addressed. The community
should also be involved in discussing which if any disclosure measures are considered necessary
and appropriate, such as signage.
Additionally, based on the work of cities such as Berkeley, San Francisco, and Los Angeles, Palo
Alto has a variety of opportunities to expand and better connect its earthquake mitigation
program efforts to other city efforts in support of community resilience goals more broadly. For
instance, Palo Alto could encourage building occupancy and resumption program like San
Francisco, encourage or fund installation of strong motion instruments, or pursue special
programs or requirements for cell phone towers, facades, private schools, and/or post-
earthquake shelter facilities. Several leading local program models and planning resources for
these types of efforts are introduced in Appendix D.
1. INTRODUCTION
This document is meant to be a resource and guide for the Palo Alto community and city
leadership as they weigh program needs and options for seismic mitigation policymaking going
forward. It offers comprehensive information on many topics so readers with different
backgrounds can advance their understanding, along with summary tables and conclusions
specific to Palo Alto’s present effort.
The approach taken was to document and assess existing and proposed programs that a
selected set of other jurisdictions are using to address earthquake vulnerabilities in local
buildings. This was done using analysis of city websites and documents, search and review of
published and online reports, several phone interviews with local officials and engineering
profession leaders, and development of insights from the consulting team based on their
experiences in this area.
Focusing on a selected set of jurisdictions was appropriate for several reasons. First, relatively
few jurisdictions are developing leading earthquake mitigation programs, and those are the
most informative models to draw upon. Second, data about jurisdictional programs is very
limited. Much of the information that does exist is anecdotal, and it was not within the scope of
this review to collect comprehensive new data or to cover a large number of jurisdiction
programs statewide or in other countries. Finally, this review emphasizes classification of
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similarities and distinctions among a range of leading jurisdiction earthquake structural
mitigation efforts. Policies related to wider earthquake hazard science and awareness,
emergency management, and longer term recovery programs that have local relevance are
briefly mentioned, but are also beyond the scope of this report.
Following this introduction, Section 2 describes and compares a range of existing local policies
and programs. The information is organized by key features (for instance, the types of buildings
regulated, the kinds of requirements imposed on them, and the types of incentives offered).
Section 3 presents summary conclusions for Palo Alto. Figures throughout and two appendices
provide further detail on a range of program elements. Formal recommendations for Palo Alto
will evolve after completion of other project tasks, and through the process of Advisory Group
and City staff discussions.
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2. ANALYSIS OF POLICY FEATURES AND OUTCOMES OF LOCAL SEISMIC RISK MITIGATION PROGRAMS
This section analyzes the state of local earthquake policymaking in California by presenting
major types, similarities, and differences in program features. The word “features” indicates
here a wide array of program nuances, including but going well beyond the characteristics of
the buildings being targeted and the basic policy mechanism used, namely voluntary or
mandatory retrofit requirements. Woven throughout are examples of jurisdictional programs
that exemplify certain of these features and distinctions, along with discussion of program
outcomes and effectiveness. Analyzing programs this way highlights options and key factors
that Palo Alto should consider and tradeoffs it may need to confront in developing its own
seismic mitigation strategy going forward.
Much innovation in local earthquake risk reduction policy is happening in California from which
Palo Alto can learn. This is particularly true in the case of soft-story wood frame residential
buildings,23 for which mandatory retrofit ordinances are now in place in Fremont, San
Francisco, Berkeley, and Los Angeles. However, what makes one program different from or
more successful than others cannot be understood simply by identifying the types of structures
addressed. Also important are the specific set of requirements that owners must comply with,
the timeframes in which requirements must be carried out, and the types and sizes of the
incentives offered.
Comprehensive, summary information to inform this review are rare. In-depth California
Seismic Safety Commission URM reports cover every city and county for URM law compliance
up to 2006. But beyond URM programs, data to support this assessment was limited and largely
anecdotal because comprehensive research on seismic mitigation programs is rare. An
23 “Soft-story” refers to a condition where one of the stories in a multi-story building, usually a parking level that
doesn’t require partitions for functionality, is weaker and/or too flexible compared to the story above it. Another
acronym sometimes used is “Soft-, Weak-, or Open-Front” buildings, or SWOFs. During strong ground shaking,
concentration of damage in the soft or weak story can significantly increase the chance of collapse or damage
sufficient to render the building unusable after the event. Many communities are concerned with soft-story wood
frame buildings. Most of this type of construction can be found in apartment buildings built in the 1960s and
1970s with first floor garage openings and some mixed-use properties with ground floor commercial space. In that
era, the safety risks of soft-stories were not yet fully understood. Vast numbers of these buildings exist in California
communities that grew substantially prior to the 1980s and 90s when building code changes were introduced.
Findings related to evaluating and improving soft-story wood frame performance can be found in FEMA P-807,
available at: https://www.fema.gov/media-library/assets/documents/32681 (Accessed February 3, 2016).
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Association of Bay Area Governments (ABAG) survey that collected program information from
one third of California jurisdictions in the 1990s documented a wide variety of program
implementation, effectiveness, and incentive approaches; however, its information is now
significantly out of date. Policies of certain leading jurisdictions have been studied in depth at
various windows in time, such as Palo Alto ) (Herman et al, 1990), Berkeley (Rabinovici, 2012;
Chakos, 2002), Oakland (Olson, 1999), and Los Angeles (Comerio, 1992). These studies reveal
how unique and complicated local earthquake mitigation programs can be, not just in format
but also implementation. Outcomes cannot be understood without considering the local
building stock and economic context, concurrent policy developments, political support, local
government resources and administrative capacity, how policy features are combined,
community engagement strategies used, and emphasis put on enforcement.
At the outset, Palo Alto’s unique current program and historic role in the evolution of
earthquake mitigation program design should be recognized. Its 1986 law was among the first
to require owners of suspected hazardous properties to have a qualified engineer evaluate
their buildings. In addition, Palo Alto’s Seismic Hazards Identification Program (Chapter 16.42)
addressed three categories of buildings: URM buildings (Category 1), structures built before
1935 with over 100 occupants (Category 2); and structures built before August 1976 with over
300 occupants (Category 3). This demonstrates how occupancy level and year built can also be
used in combination with other factors as the basis for inclusion in a program. The mandatory
evaluation reports for these structures were due in 1990. The September 2014 status of
affected properties is shown in Table 1.
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Table 1: Status as of September 2014 of properties included under Palo Alto’s current earthquake
risk reduction ordinance.
Category I – Category II – Category III –
All Categories URM over 1900
sq.ft. and over
six occupants
Built before 1935
and over 100
occupants
Built before
8/1/76 and over
300 occupants
Retrofit 22 13 5 40
Demolished 14 2 5 21
Demolition
Proposed 0 0 4 4
Exempt 1 0 0 1
No Change 10 4 9 23
Totals 47 19 23 89
Source: 12/9/14 City of Palo Alto Policy and Services Committee staff report.
Palo Alto’s decision to focus on these three categories grew out of a broader earthquake risk
assessment effort going on at that time. City leaders initiated a comprehensive search of paper
records and a street walk-style inventory of a wide variety of seismically-vulnerable building
types in 1984. They then engaged the community in a deliberative process to assess risk and
determine priorities among building types and policy approaches (Herman, Russell, et al. 1990;
CSSC 2006).
The following section describes alternative ways different jurisdictions have chosen which
buildings to target.
Scope: Targeted Structural Systems, Year Built, and Other Characteristics
The primary feature that varies among jurisdictional programs is the types and characteristics
of the structures that are addressed. As discussed in the Task 2 report, California’s earthquake
policy history started in the 1930s with laws that increased design requirements for buildings
related to one particular use—public schools, and banned new construction of one particular
structural system or type—buildings with unreinforced masonry (URM) load bearing walls.
Much later in the 1970s and 80s, both state and local new laws were passed targeting URMs
built before 1933, certain locations (e.g., hazard zoning with prohibitions or heightened
evaluation and design scrutiny for new construction or rehabilitation in those zones), a wider
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set of uses (e.g., hospitals and essential services buildings) and additional structural types (e.g.,
older concrete buildings and manufactured homes).
The choices jurisdictions make about which buildings to target are closely tied to the legal basis
underlying earthquake mitigation policymaking. Laws that impose added burdens or
responsibilities on certain properties or people must clearly specify which buildings are
applicable and justify why for those particular buildings have been selected. A compelling,
documentable, and actionable public purpose must exist to invoke a jurisdiction’s police
powers and responsibility for public wellbeing.
The central rationale for regulating seismically vulnerable structures is safety; a strong case for
government intervention exists where there is an unacceptably high likelihood of collapse or
damage that could lead to human entrapment, injury, or death. Technical research, evidence,
and evolving standards of practice in structural engineering must exist for this to be considered
reasonable. Once a new practice becomes embedded in a model building code, construction to
former code standards is no longer allowed. Jurisdictions review permits and inspect
construction work in progress, but lax compliance cannot entirely be ruled out.
For any particular structural system, year built (or age) is the most commonly used risk
indicator because it reflects the building code version that was in effect when a structure was
first constructed. What was once considered an acceptable construction practice may become
obsolete or even be considered negligent years later. Code updates are usually made on a
three-year cycle to keep up with changes in construction practices, technologic advancements,
and improved understanding how buildings perform under loads, but adoption by jurisdictions
can be uneven and lag behind many years.
Jurisdictions must also address which code year built they will use as inclusion criteria for their
earthquake mitigation programs. Benchmarking to newer standards may be justified if it
reaches more buildings that could experience significant damage in an earthquake, but a larger
percent of building owners and tenants will be affected. Code changes are also proposed based
on lessons learned from practical experience over time, in this case from earthquake
performance outcomes in jurisdictions all around the world.
Unreinforced Masonry Buildings
URM buildings have been a concern for collapse and falling debris hazard ever since the
1933 Long Beach earthquake, after which new construction of URM structures in
California was outlawed. The most significant contemporary law addressing a specific
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building type is the 1986 state legislation (Senate Bill 547). This state mandate, also
summarized in the Task 2 report, required jurisdictions to identify and adopt programs
for addressing existing URM buildings. Several jurisdictions (most prominently Long
Beach, Los Angeles, Santa Cruz, Palo Alto, and San Francisco) had existing URM building
ordinances and programs in place prior to the state mandate. Counties and
municipalities were allowed to craft their own approach, resulting in a wide range of
strategies.
In general, three main types of local programs were utilized: 1) mandatory retrofit, 2)
voluntary retrofit, and 3) notice to owners that the structure is a URM building. When
retrofits were encouraged or required, the local government set the standards to be
met. More than half (52%) of affected jurisdictions adopted a mandatory program,
which has proven by far to be the most effective type. Eighty-seven percent of identified
properties have been retrofitted or demolished in jurisdictions with mandatory
programs, compared to thirteen to 25 percent in jurisdictions with other program types.
Reviews of the URM Law by the CSSC have shown it to be a success over the long term.
In 2006 (the last comprehensive state survey available), Compliance with the policy is
nearly universal at 93%, and over 70% of identified URM buildings have been either
retrofitted or demolished (CSSC, 2006). A comprehensive review of URM program
formats throughout the Western United States is available from FEMA and the California
Seismic Safety Commission (FEMA, 2009; CSSC, 2006).
Older Concrete Buildings
Older concrete structures (built pre-1970s and in some cases pre-1990s) exemplify the
importance and difficulties of using code year as an indicator of seismic risk. Public
awareness of older concrete risks may be lower than for soft-story wood frame
buildings, but they are common in large numbers in the Western US and throughout
California. The Concrete Coalition,24 a network of engineers, research organizations, and
policymakers, estimates that there are as many as 17,000 non-ductile concrete buildings
in California (Concrete Coalition, 2011). The societal importance of older concrete
structures can be significant, as they often have higher occupancies and are widely used
for residential tall buildings, commercial, or even critical service facilities.
24 Information about the Coalition can be found at the organization’s website: http://www.concretecoalition.org/,
Accessed March 18, 2016.
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Poorly performing concrete structures can have devastating effects for occupants,
owners, and communities, as numerous major quakes in California and abroad have
demonstrated. The 1971 Sylmar earthquake brought down several concrete structures,
killing 52, and the 1994 Northridge earthquake wrecked even more, including a Bullock's
department store and Kaiser medical office. In the 2011 quake in Christchurch, New
Zealand, two concrete office towers collapsed killing 133 people. Many of the 6,000
people killed in the 1995 earthquake in Kobe, Japan, were in concrete buildings.
A scenario report for the San Francisco Bay Area estimates that older concrete buildings
in a repeat 1906-level event would contribute a large portion of the predicted deaths
and injuries (ABAG, 1999). Also at risk are investors, the survival of occupying
businesses, and livelihoods. Neighborhoods can be at risk too if a district has a high
concentration of older concrete buildings, as they may be blighted or loose functionality
or economic viability after an event.
Older concrete buildings of concern have a variety of features and are not always easy
to characterize. One issue is nonductile (essentially too brittle, insufficiently reinforced)
concrete, prior to enforcement of ductile concrete codes in the 1970s. Another is tilt-up
structures, where a concrete is poured on the ground, cured, and then lifted (or “tilted”)
up and connected to roof and floor framing where the ties between the roof and wall
and floors and walls are often inadequate.
Vulnerable concrete structures can be difficult to spot and often complex to retrofit
(ATC, 2012). These are factors in why only a small number of California jurisdictions
have adopted policies for older concrete (Table 2). The City of Los Angeles (Building
Code Divisions 91 and 96) recently required evaluation and upgrade if needed for
nonductile concrete structures and since Northridge has required triggered upgrading
on pre-1976 tilt-ups. City of Santa Monica (Municipal Code 8.80) requires evaluation and
upgrade if needed for nonductile concrete structures, along with other structural types.
In 2014 Santa Monica hired the engineering firm Degenkolb to inventory buildings that
might be subject to its requirements—a first step in reviving efforts that had been
stalled for more than 20 years.25 Two jurisdictions, Long Beach (Chapter 18.71) and
Burbank, have taken the approach of providing voluntary guidance. Burbank’s program
addresses older reinforced concrete and concrete frame buildings with masonry infill.
25 http://www.latimes.com/local/lanow/la-me-ln-santa-monica-will-hire-quake-engineers-to-id-all-vulnerable-
buildings-20140527-story.html (Accessed March 20, 2016).
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Table 2: Summary table of local programs for addressing older concrete building vulnerabilities.
Jurisdiction
Number
of Older
Concrete
Buildings
Program
Type
Targeted
Building
Characteristics
Deadline
for
Screening
Deadline
for
Evaluation
Deadline
for
Completion
Los Angeles Unknown
(Concrete
Coalition
inventory*
= 1500)
Mandatory
evaluation
leading to
mandatory
retrofit
Pre-1976 tilt-
ups and
nonductile
concrete
3 years 10 years 25 years
Santa Monica Unknown
(Concrete
Coalition
estimate*
= 173)
Mandatory
evaluation
leading to
mandatory
retrofit
Pre-1978
nonductile
concrete.
n/a 275 days Deadlines
vary from 1
to 4 years
after
evaluation
report
submission,
depending
on priority
tiers. **
Long Beach Unknown
(Concrete
Coalition
estimate*
= 396)
Voluntary
guidance
Nonductile
concrete
n/a
Burbank Unknown
(Concrete
Coalition
estimate*
= 132)
Voluntary
guidance
Commercial
pre-1977
reinforced
concrete and
concrete frame
buildings with
masonry infill
n/a
* Source: (Concrete Coalition, 2011).
** Santa Monica’s Building Type definitions are: Type I: building that are vital in the event of an
emergency; Type II: >100 occupants; Type Ill: 20 - 100 occupants; Type IV: < 20 occupants.
Soft-Story Wood Frame Buildings
Wood frame soft-story buildings are a good example of a vulnerable building type that
gained widespread attention after performing poorly in specific earthquake events. In
October 1989, the hazard and widespread presence of this building type were made
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evident by the dramatic and costly collapses and fires in the San Francisco Marina
District in the Loma Prieta earthquake. Then again, in the Northridge event in 1994,
widespread damage and several high profile collapses occurred. The Northridge-
Meadows apartment complex collapse that led to sixteen deaths in particular captured
media, public, and expert attention.
Following these events, soft-story residential buildings started to be viewed as not just a
threat to the owner’s pocketbook but to the surrounding community; tenant safety and
local recovery could also be at stake. Given their prevalence, losing hundreds of soft-
story apartment buildings could have large impacts on community. For example, soft-
story buildings constituted about half (7,700) of the 16,000 housing units rendered
uninhabitable in the Bay Area by the 1989 Loma Prieta Earthquake and over 34,000 of
the housing units rendered uninhabitable by the Northridge Earthquake in 1994 (ABAG,
2003). Table 3 describes a wide range of local efforts to address soft-story wood frame
buildings, highlighting key program features and distinctions (many of which are
discussed in later sections regarding prioritization, timing, and policy mechanisms).
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Table 3: Summary of local soft-story wood frame policy efforts showing key distinguishing program features.
(Sources: Rabinovici, 2012; ABAG, 2016).
Jurisdiction Year
Number
of Soft-
story
Buildings
Program
Type
Targeted Building
Characteristics Priorities or Tiers
Deadline
for
Evaluation
Deadline
for
Permit
Deadline
for
Completion
Los Angeles 2015 unknown
Mandatory
Evaluation
leading to
Mandatory
Retrofit
Pre-1978 wood-
frame structures
with soft, weak or
open front first
floor conditions
with two or more
stories and five or
more units. Only
enforcement is
prioritized by
tiers.
Priority I - Buildings
containing 16 or more
dwelling units.
1 year 2 years 7 years
Priority II - Buildings with
three stories or more,
containing fewer than 16
dwelling units.
Priority III - Buildings not
falling within the
definition of Priority I or II.
Oakland 2015 1,380 Mandatory
Screening
(passed
2009)
leading to
Mandatory
Retrofit
Pre-1985 multi-
family wood
frame structures
with five or more
units
n/a
Attachment F
Table 3 (continued).
Seismic Risk Assessment Study December 21, 2016
Final Report Page 39
Jurisdiction Year
Number
of Soft-
story
Buildings
Program
Type
Targeted Building
Characteristics Priorities or Tiers
Deadline
for
Evaluation
Deadline
for
Permit
Deadline
for
Completion
Berkeley 2014 310 (at
time of
2005
ordinance)
Mandatory
evaluation
law (2005)
leading to
mandatory
retrofit
(2014)
Multi-family wood
frame structures
with five or more
units
n/a 2 years
(under
previous
soft-story
evaluation
ordinance)
2 years 4 years
San Francisco 2013 2,800
Mandatory
evaluation
leading to
mandatory
retrofit
Wood frame
construction with
five or more
residential units
and two or more
stories with
permit for
construction
submitted prior to
January 1, 1978
and five or more
units
Tier I - Any building
containing educational,
assembly, or residential
care facility uses (Building
Code Occupancy E, A,
R2.1, R3.1, or R4)
1.5 years 2.5 years 4.5 years
Tier II - Any building
containing 15 or more
dwelling units
2.5 years 3.5 years 5.5 years
Tier III - Any building not
falling within another tier
3.5 years 4.5 years 6.5 years
Tier IV - Any building
containing ground floor
commercial uses (Building
Code Occupancy B or M),
or any building in a
mapped liquefaction zone
4.5 years 5.5 years 7.5 years
Attachment F
Table 3 (continued).
Seismic Risk Assessment Study December 21, 2016
Final Report Page 40
Jurisdiction Year
Number
of Soft-
story
Buildings
Program
Type
Targeted Building
Characteristics Priorities or Tiers
Deadline
for
Evaluation
Deadline
for
Permit
Deadline
for
Completion
Alameda 2011 70 Mandatory
evaluation
Five or more units n/a 2 years
Fremont 2005 22 Mandatory
retrofit
Apartment house
with more than
ten units or more
than two stories
Group 1 - Apartment
house with more than ten
units or more than two
stories
n/a 2 years 4 years
Group II - Apartment
house with ten or less
units and fewer than three
stories high
n/a 2.5 years 5 years
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 41
Public Purpose, Occupancy, Location, and Other Considerations
Another stated goal of seismic mitigation laws is to promote continuity of vital services
related to the community’s social and economic viability. In addition to direct safety
concerns, this further justifies targeting special uses and buildings that affect larger
numbers of people such as schools, critical public buildings, and hospitals. Beyond
critical community functions, however, it is less obvious where to draw the line between
public and private risks and benefits. How many people need to live or work in a
building before a suspected earthquake vulnerability becomes something an owner or
tenant should not be allowed to make decisions about on their own?
The answer involves some sense of proportionality. In other words, local governments
tend to seek a reasonable balance between the number of building owners that will
need to comply and the burden of compliance, with the public benefits that will be
achieved (which we can assume to be protection of health and preservation of
community functionality). That is a key reason why buildings with higher occupancy or
higher residential unit total are sometimes targeted. Such buildings not only have more
human beings that work or live in them, but the fate of the buildings also has a larger
impact on local housing availability, parking, and other community impacts. For
instance, most existing soft-story wood frame programs are targeted at multifamily
buildings with five or more residential units (see Table 3). Larger structures are also
presumably worth more, so the owner is more likely to have sufficient equity in the
property or cash flow to make capital upgrades.
A structure’s number of stories may also relate to the degree of risk or perceptions of
public importance. Problematically, more stories may not always translate into higher
risk; for example, two-story soft-story buildings may not necessarily be less dangerous
compared to three story ones, depending on the materials used and the positioning of
occupied units (Bonowitz and Rabinovici, 2012).
A good example of a program that uses location or zoning as part of its targeting is Palo
Alto’s Municipal Code Chapter 18.18.070 Floor Area Bonuses incentive. The incentive is
only available for buildings in Commercial Downtown (CD) District, which has sub-zones
based on CD-C Commercial, CD-S Service, and CD-N Neighborhood designations. Zoning
benefits are different for each of these designations, the square footage, and also if the
building in question is historic property.
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Ownership structure is another potential scoping issue, for instance, whether
condominiums should be included.26 The City of Berkeley did not include condominiums
in its soft-story wood frame building ordinance, but the jurisdictions of San Francisco
and Fremont did. Condominiums often face additional barriers in both voluntary and
mandatory retrofit policy settings, because homeowner association policies and
practices can make it difficult to agree on what should be done and to obtain financing.
Anecdotally, in Palo Alto and elsewhere, properties where a majority of owners want to
retrofit have not been able to accomplish that work because of hold-out members that
do not want to proceed or pay an additional assessment in order for the association to
be able to afford it. The overall influence on retrofit behavior of either including or
excluding condominiums is not known.
A final point that should be noted about program scope is that some properties that would
otherwise be subject to a law can be classified as exempt for certain reasons. For instance, most
jurisdictional ordinances offer exemptions for buildings that have had significant recent
renovations or retrofit upgrades that addressed the hazardous condition. Some jurisdictions
explicitly include protocols for hardship provisions such as extended timelines that might be
made available for individual or institutional owners that can demonstrate an unusual degree of
difficulty raising sufficient funds to comply.
Timelines, Pacing, and Prioritization
For several reasons, jurisdictions find it useful to both prioritize and pace their earthquake
program efforts. Time is a powerful ally and policy variable. Once a jurisdiction commits to the
idea of a new program, timeframes can be used to make implementation manageable and
soften the economic impacts of the program on city staff and budgets, on owners, and on the
local economy. Retrofitting is also a process that cannot be sped up beyond a certain point.
Design, arrangement of financing, and completion of retrofit work can be an arduous process,
naturally taking from months to years. Lengthier time windows allow owners to plan for how to
comply in the way that works best for them. Longer time frames can also work to the
advantage of jurisdictions, which rarely have sufficient administrative capacity, political will,
and community tolerance to take on multiple seismic risk issues simultaneously over a short
26 Keep in mind that condominium status can change. The City of Berkeley decided not to include condominium
properties on its Suspected High Hazard Building list. However, owners in some apartment buildings in the process
of being converted to condominium status when needing complying with the law experienced difficulty getting
loans (Rabinovici, 2012).
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 43
period of time. Following are several examples of how different jurisdictions have used timing
as part of their program structure.
Trigger-Enforced Timing
Some jurisdictions have opted to require earthquake retrofit to be done only when the
property is sold and/or an owner submits plans for renovation, additions, or
rehabilitation that meets certain criteria, for instance 50% of the assessed value. This is
similar to triggers for energy upgrading, sewer lateral replacement for single family
homes, modifications for Americans with Disabilities Act compliance, or sprinkler and
other fire code changes.
A jurisdiction taking this approach does not need to inventory vulnerable structures in
advance and may be able to do project reviews at current staffing levels. However,
there are several downsides. Owners may resent encountering these potentially
substantial “surprise” costs when initiating a project, and might strategically manipulate
project valuation to avoid needing to comply, resulting in lower fees for the city. For
those owners that are aware of the provisions, potentially important non-seismic
renovation work that would have been done otherwise might be postponed as a result
of increased project cost and complexity. Most importantly, critical safety and resilience
retrofit work might go decades without being done.
Proactively-Enforced Timing with Phasing and/or Prioritization
Proactive enforcement means that a jurisdiction identifies, notifies, and actively seeks to
help owners participate or comply in a program. It is common when these programs
include mandates to use a variety of time frames for buildings with different
characteristics. For instance, Los Angeles’s 2015 ordinance requires compliance for soft-
stories within seven years and older concrete within 25 years. Another common
strategy is to classify buildings of a single targeted structural type into tiers or priority
levels among a particular type of building, for instance based on age, number of
stories, unit totals, or occupancy. Compliance can then be mandated sooner in order
from most to least serious in terms of estimated risk and social importance. Time frames
for soft-story programs, for instance, commonly relax deadlines by about one year per
tier (See Deadlines by programs in Table 3). Both of these phasing approaches allows
jurisdictions to set a feasible administrative pace and put an early focus on buildings
with vulnerabilities and characteristics that most affect the public.
Attachment F
Seismic Risk Assessment Study December 21, 2016
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An overall pacing strategy can also be used to phase implementation of a larger set of
resilience policies and programs that go beyond different building types to address
other aspects of community earthquake vulnerability. For instance, San Francisco
mandated soft-story wood frame building retrofitting, then mandated its 120 private
schools to do seismic evaluations of their buildings regardless of structure type,27 and
then embarked on efforts to assess and create programs for poorly anchored façades
and unreinforced masonry chimneys.
All three approaches – 1) phasing and compliance time frames that differ for structures,
2) in different priority tiers, 3) within a multifaceted comprehensive plan – were used in
recommendations from San Francisco’s decade-long Community Action Plan for Seismic
Safety (CAPSS) project (ATC, 2010). Figure 2 shows an earlier version of how San
Francisco thought about address different building types and uses more or less quickly
and with gradually increasing requirements.
Later, these concepts were embedded into the jurisdiction’s policies as part of San
Francisco’s 30-year Earthquake Safety Implementation Plan (SF ESIP, 2011). That plan
represents a commitment by the city to phase in additional efforts over this extended
period, and deliberately addressed a wide range of vulnerable structure types, uses, or
occupancy combinations considered important to community resilience (e.g., private
schools, façades). Additional advantages of long time frames are to allow more time for
detailed studies or research if needed, for political or community consensus to develop,
and give owners ample notice of bigger changes to come.
27 Ordinance text available at: http://sfgov.org/esip/sites/default/files/FileCenter/Documents/12716-
Ordinance%20No%20202-14%20Private%20Schools%20EQ%20Evaluation.pdf (Accessed February 3, 2016).
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Figure 2: Excerpt of Table 5 from the summary San Francisco CAPSS Project report (ATC, 2010)
showing recommended timelines for prioritizing and phasing different kinds of efforts to address
a variety of building types and uses.
Note: Categories represented in rows are not mutually exclusive. For instance, some private school
facilities may be located in a house of worship or historic structures.
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 46
Policy Mechanisms and Requirements
In addition to creating a set of targeting and eligibility criteria, jurisdictions can use a variety of
methods to motivate appropriate seismic upgrades to be done. Requiring owners to do retrofit
work is only one approach. Other tools range from simple notification, disclosure measures,28
offering incentives, voluntary retrofit initiatives, and mandated screenings or evaluations, each
of which is described below in more detail. Another major distinction is whether a jurisdiction
implements requirements only when triggered during rehabilitation projects that meet certain
criteria, or proactively, such as doing an inventory to identify affected properties and imposed
deadlines.
Figure 3 provides definitions of a spectrum of policy mechanisms that have been used. This
view corrects the false impression that jurisdictional programs have to be either “voluntary” or
“mandatory.” In reality, most jurisdictions create a policy package that combines several
approaches. Furthermore, that package can evolve over time as more and more buildings are
upgraded, new information or technical recommendations become available, or with changes
in the political or economic climate.
Inventory
Identifying the number and locations of buildings of concern is an essential first step to
finding out which buildings are the most vulnerable and how significant those issues
may be for the community. Many jurisdictions launch their earthquake program
development process with a special-purpose, one-time discovery effort meant to
compile data about potentially seismic at-risk properties and to gauge the scope of the
issues faced by the community. This can be difficult and time consuming, and
jurisdictions often rely on outside consultants or professional organizations and
academic volunteers for assistance. Existing property databases generally contain less
than complete information to be able to draw conclusions, and some relevant
information may only exist in paper form. Street-walks, side walk surveys, or visits to a
selected sample of properties are common.
It is important to distinguish early investigation and risk analysis efforts that might
involve only a subset of properties from the development of an exhaustive list of
properties meeting certain criteria that could be officially noticed or subjected to a
28 Disclosure policies are designed to increase the transparency and openness surrounding an issue of social
importance. Examples include mandatory disclosure to tenants, freedom of information requirements, public
signage, searchable online listing, or official notice placed on a title or deed. These are described in Table .
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 47
particular ordinance. The City of Berkeley is one jurisdiction that used a list created by
staff and consultants as the basis for determining which properties should be included
on that city’s suspected hazardous properties list. Other cities have instead chosen to
put buildings on an initial suspected hazard list based on zoning, number of units, or
other generally available criteria.
Palo Alto’s current investigation into updating its seismic risk management program
involves review of digital records, paper records, and side walk surveys. The side walk
survey portion includes approximately half of the buildings of interest. A similar
detailed field effort would be needed on the remaining portion of buildings to develop a
comprehensive inventory list.
No inventory list will be perfect, so no matter which approach is used, some kind of
appeal, confirmation, or screening processes are needed before granting any
exemptions or enforcing requirements. Depending on the building type, issues of
improper inclusion or exclusion from a list may be more or less likely. For example,
rapid visual determination is easier for wood frame soft-story conditions, but it would
be hard for even an experienced engineer to identify a steel moment frame, braced
frame building, or a concrete frame building when the structural elements are hidden
from view by architectural finishes.
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 48
Figure 3: Diagram showing a spectrum of mitigation policy approaches ranging from least to most stringent.
Inventory Only Notify Only Voluntary
Retrofit
Disclosure
Approaches
Mandatory
Screening
Mandatory
Evaluation
Mandatory
Retrofit
Staff, consultants,
and/or a volunteer
organization has
created an
inventory of one or
more suspected
hazard building
types, but the list is
not officially
released to the
public or acted
upon.
An inventory exists
and a policy has
been established to
notify owners if
their property is on
a suspected hazard
building list.
Owners of
properties on a
publically available
list are formally
encouraged to
retrofit, possibly by
offering of technical
assistance, financial
help, or policy
incentives.
Properties on a
publically available
list are subject to
one or more
methods of forced
information
sharing, such as
tenant notification,
public signage, or
recorded notice on
the property title.
Owners of
properties on a
publically available
list are required to
submit a form
within a fixed time
window that is filled
out by a licensed
building
professional.
Typically, the goal is
to determine
whether the
property has certain
characteristics that
might associate
with risk.*
Owners of
properties on a
publically available
list are required
submit within a
fixed time window a
formal evaluation
completed by a
licensed engineer.
Typically, a
determination is
then made about
whether the
property has certain
risk features.*
Owners of
properties on a
publically available
list are required to
complete a retrofit
by a certain date.
This step may be
implemented
following a
screening or
evaluation phase.*
* Note: Implementation and enforcement might be either: 1) triggered by sale or a significant work threshold or 2) via a proactive compliance timeline.
Increasingly Stringent
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 49
Notification
Once an inventory is created, a jurisdiction either by default or deliberately chooses
whether or not to make that list public or take further actions. Some jurisdictions have
created a list then not acted on it for a decade or more. For example, in the case of soft-
story wood frame buildings, Santa Clara County’s list has remained dormant since 2003,
and nine years passed between the creation of a list and when the City of Berkeley
passed its soft-story ordinance.
The most basic step is to notify owners that their property is on some kind of suspected
earthquake hazard list. This is currently the URM policy of a small number of California
jurisdictions, and the soft-story wood frame policy in the jurisdictions of San Leandro,
Sebastapol, and Richmond. Available data about notification only programs shows them
to have little impact; for instance, seven percent of URM properties in jurisdictions with
this type of program are retrofit as of 2006 (CSSC, Status of the Unreinforced Masonry
Building Law, 2006).
Little evidence exists about potential liability and market value impacts from becoming a
“listed” earthquake vulnerable building. However, concern exists that mere creation of a
list could have negative impacts if it becomes public (see more about Disclosure
Approaches below). A Freedom of Information Act (FOIA) filing (for instance, by a
journalist or citizen) could be used to compel a jurisdiction to reveal a list that has
remained dormant. This happened in the case of Los Angeles with the Concrete
Coalition’s inventory of suspected concrete structures.29 Experts in the earthquake field
believe that media coverage of the list contributed to eventual passage of that city’s
mandatory evaluation ordinance in 2015, which included concrete structures. In sum,
notification programs may have several downsides for owners while offering little in
terms of on the ground risk reduction for the community.
Voluntary Retrofit
Following an inventory and notification process, or even after a mandatory screening or
evaluation phase (see below), jurisdictions can choose to let owners decide whether or
not to retrofit their building. Simply urging building owners that own a potentially
earthquake vulnerable building may be enough to lead some to voluntarily retrofit.
29 Key Los Angeles Times articles can be found at: http://graphics.latimes.com/me-earthquake-concrete/ and
http://www.latimes.com/local/lanow/la-me-ln-concrete-buildings-list-20140125-story.html (Accessed April 11,
2016).
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Retrofit rates for jurisdictions with voluntary URM retrofit programs averaged 16% in
2006 (CSSC, Status of the Unreinforced Masonry Building Law, 2006), and likely much
lower than that for soft-stories (though no systematic data currently exist).
Jurisdictions that take a voluntary route often do so because they have a small number
(presumably less socially-significant set) of vulnerable buildings. Another factor can be a
sense that public support is lacking among decision makers, residents, or other
stakeholders for mandatory requirements, perhaps because of local economic
conditions that would make it difficult for owners to afford or get financing. The
anticipated cost of the retrofit work can also come into play, as it can be more palatable
to require owners to make investments that are a smaller share of the building’s overall
value.
Despite perceptions of politically feasibility and some measurable voluntary retrofit
response, programs without mandates are almost always much less effective at actually
reducing earthquake risk in the community in a significant way. Several factors appear
to contribute to the handful of voluntary programs that have worked well. First and
foremost, voluntary programs vary in the level of resources devoted, sustained effort,
and set of complementary measures taken by the jurisdiction. The more dedicated a
jurisdiction is to having a successful voluntary program, the more likely it is to have one.
One tactic is to provide case by case assistance to owners in taking steps over time, a
tactic sometimes used by jurisdictions with a small number of affected buildings.
Another is to offer significant financial or policy incentives (examples of which are
discussed below). On the public awareness front, providing educational materials that
explain the risks to an owner and to the broader community and the benefits of
protecting their financial investment may help.
Another thing that can make voluntary programs more successful is to threaten to
institute a mandatory program in the future. Historically, many jurisdictions did adopt a
voluntary URM program first, and then shifted to mandates later on. In the past five
years, this has also happened with soft-story wood frame policies in the case of
Oakland, San Francisco, and Berkeley. An explicit multi-phased approach was
particularly effective in Berkeley, where one fourth of building owners affected by a
mandatory evaluation requirement invested in a voluntary retrofit within the first two
years. Owner interviews showed this was partly because they wanted to get a head start
on later mandates that appeared inevitable (Rabinovici, 2012).
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Disclosure Approaches
Notification and many voluntary programs are based on the idea that information and
communication by themselves can influence the opinions and actions of owners,
renters, and buyers. Officially publicizing a city’s concerns about deficiencies of a
specific building type could, for instance, change public opinion about the resale or
rental value of listed properties, an owner’s eligibility for refinancing or future loan
terms, or the cost of purchasing earthquake insurance.
Jurisdictions have used a variety of techniques to motivate attention to seismic risk
concerns. As discussed in the Task 2 report, mandatory disclosure at time of sale is a
key part of state laws for pre-1960 homes in earthquake fault zones (CSSC, 2005). The
most prominent policy is the state requirement for signage on all URM buildings. Similar
signage has been required since 2007 on soft-story wood frame buildings in the City of
Berkeley (Figure 4), and non-complying soft-story wood frame buildings in San Francisco
Figure 5.
In Oakland, Berkeley, and San Francisco tenants must be notified in writing, and official
notices are recorded on the deed for all listed soft-story wood frame buildings.
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Figure 4: Photo of the warning sign mandated to be posted on buildings on the City of Berkeley’s
Suspected Earthquake Hazard Building List (Photo: S. Rabinovici, 2011).
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 53
Figure 5: Required placard for soft-story wood frame buildings that failed to comply on time with
the mandatory screening phase of San Francisco's mandatory retrofit program.
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 54
In the case of soft-story wood frame buildings, leading jurisdictions have also put a
public, sometimes searchable list of affected properties on a jurisdiction’s website,
based on the idea that renters should be entitled to easily accessible information before
they sign a lease. Such lists include the street address and potentially also the
compliance status of the property. Owner names or contact information are not given,
although anyone could search for that information through public permit and property
records. Table 4 describes each of these tools in more detail and gives examples of use
as well as advantages and disadvantages.
What all these measures have in common is that they make seismic risk issues more
transparent and visible to affected members of the public. Disclosure is different than
and goes beyond general public awareness. These measures are also meant to inform
people about specific seismically vulnerable buildings, with the idea that it might change
offering prices, mortgage availability and terms, rental or purchase decisions, or even
whether someone wants to enter or stay very long in a building. In theory, as owners,
tenants, bankers, and potential buyers become more informed, they can better
incorporate seismic risk in their mitigation decisionmaking and assessment of property
values.
Evidence suggests that notification, notices, and public lists can and do influence beliefs
and behavior. For example, some soft-story wood frame condominium owners in
Berkeley reported difficulty refinancing (Rabinovici, 2012). Even perception of market
awareness can change opinions, even if there is little to no documented impact. In
Berkeley, some owners said the worried at first about reduced demand or market price
for units in their buildings and this motivated them to retrofit; however, these same
owners years later did not report experiencing any problems with tenant recruitment or
lost rental income (Rabinovici, 2012).
Earthquake warning signage was a prominent part of the state’s URM program
requirements; however, there is little evidence to show that such warnings are
effective. A study of California Proposition 61 carcinogen and reproductive health
warnings suggests that signs are not very powerful and become less influential on
behavior over time as people become used to them. Some building users may even be
personally annoyed by warning signs, because it reminds them of a risk that they can
personally do little about. Some owners of soft-story wood frame buildings in Berkeley
Attachment F
Seismic Risk Assessment Study December 21, 2016
Final Report Page 55
reported having tenants that actively complained about or repeatedly ripped the
required warning signs off the walls (Rabinovici, 2012).
Attachment F
Seismic Risk Assessment Study December 21, 2016
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Table 4: Description of disclosure approaches used in local earthquake risk reduction programs.
Name Description Examples of Use Advantages Costs, Issues or Concerns
Mandatory Disclosure
at Time of Sale
Sellers of property are required
to disclose features that could
relate to earthquake
performance.
California Earthquake
Fault Zone disclosure;
Sellers of pre-1960
homes are required to
fill out to the best of
their knowledge and
provide buyers with
Residential
Earthquake Hazards
Report.
Empowers buyers to be
aware of any known
existing hazard issues.
Anecdotally, many buyers do
not pay enough attention to
these disclosures, which occur
during emotional, busy
decisionmaking periods. They
may not seek expert
information to interpret the
reported information. It is also
possible that sellers shirk on
the disclosure requirements if
buyers do not know that they
are supposed to receive them.
Difficult to enforce.
Recorded Notice on
Deed
Jurisdictions can record on the
property title or deed the fact
that the building is subject to
additional requirements
related to its earthquake
vulnerable status.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Relatively low cost for
jurisdictions to implement.
Empowers buyers but also
mortgage companies to be
aware of any known
existing hazard issues.
Anecdotally, it is not clear how
many buyers or mortgage
companies pay attention to
these notices. Such notices are
primarily effective only at time
of sale or refinance.
Attachment F
Table 4 (continued)
Seismic Risk Assessment Study December 21, 2016
Final Report Page 57
Name Description Examples of Use Advantages Costs, Issues or Concerns
Public Listing of
Affected Properties
Jurisdictions that operate web
sites to describe their
programs can feature a full list
of property addresses,
potentially also including also
the compliance status of the
property. In general, owner
names are not listed, though
that information is available if
a member of the public
searched for it separately.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Relatively low cost for
jurisdictions to implement.
Could be used by tenants
and buyers when
searching for properties,
thus empowering well-
informed market
negotiations over pricing.
Website information needs to
be updated on a regular basis
in order to be perceived as fair
and useful. Public lists work
better if the property
addresses are searchable,
rather than static (e.g., on a
pdf).
External Signage Jurisdictions that operate web
sites to describe their
programs can feature a full list
of property addresses,
potentially also including the
compliance status of the
property. Some lists are
searchable, while others are
static.
California state
requires a sign on all
URM buildings. Similar
signage has been
required since 2007
on soft-story wood
frame buildings in the
City of Berkeley.
Advocates argue that signs
are justified based on the
public's right to know. The
physical presence and
repeated viewing of
signage may make the
issue more salient for
visitors, employees, lease
holders, and owners alike.
Owners may view the signs as
stigmatizing or threatening to
property value or business
revenues, but anecdotally, it is
not clear how much visitors,
employees, residents, and
other users of a building pay
attention to signage when
entering or leaving a property.
Attachment F
Table 4 (continued)
Seismic Risk Assessment Study December 21, 2016
Final Report Page 58
Name Description Examples of Use Advantages Costs, Issues or Concerns
Tenant Notification Owners are required to present
straightforward, standardized
information about the listed
status of the property. Some
jurisdictions require proof of
notification (e.g., tenant
signature) to be returned and
kept on file with the city.
For soft-story wood
frame: Oakland,
Berkeley, and San
Francisco.
Tenant notification may be
more influential than
signage because it is
personalized and the
information is delivered at
a useful time in that
person's decision process.
Advocates claim that
tenant notification is
justified based on the
public's right to know.
To be effective, tenant
notification should be required
to occur well before the
potential tenant is ready to
sign the lease.
Earthquake
Performance Rating
Systems
Owners can be either
encouraged or required to
have their building rated on a
standardized scale that
classifies expected building
performance in an earthquake
in an easier to understand
format, for instance from one
to five stars. Viable rating
systems exist for many building
types.
The City of Los
Angeles in 2015
officially launched a
voluntary effort to
encourage owners to
rate their properties
using the US
Resiliency Council
system and pledged to
rate its own public
buildings as well.
Rating system use is
common for institutions
like universities and
hospitals. Mechanisms for
implementing
performance ratings for
commercial use have
recently matured and are
now viable. Ratings have
the potential to inform
owner, renter and buyer
decisions, creating a
market effect.
Obtaining a rating potentially
adds cost to a design project.
Ratings systems such as USRC’s
are relatively new and not yet
widely implemented.
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An advantage of disclosure measures is they tend to be relatively inexpensive for jurisdictions
to administer. Up to date website posting of the list of affected properties and their compliance
status encourages people to visit the site as needed over time, people see signs every time they
enter or exit, and properties may exchange hands many times. Eventually, a tipping point in
community awareness and opinion about a class of properties can occur, as it did in the case of
Berkeley for soft-story wood frame buildings.
The use of positive disclosure remains an untapped potential influence on market value of
retrofitted properties as well as owners’ retrofit decisions. This review did not identify any city
programs that have taken the positive approach of recognizing or rewarding owners or
announcing buildings that have been retrofit. One recent development is the existence of viable
earthquake rating systems. In November 2015, the non-profit US Resiliency Council30 launched
a non-profit credentialing and verification service through which owners can obtain externally
checked, state-of-the-art assessment of the expected safety levels, repair costs, and time to
regain function for their property. USRC ratings have the potential to play the same kind of role
that the US Green Building Council did in promoting sustainable design, both for new
construction and for retrofits.
USRC’s system has already been adopted one California jurisdiction’s policy. Los Angeles Mayor
Eric Garcetti cited USRC ratings in that city’s Resilience by Design report (City of Los Angeles,
2015), asking building owners to voluntarily use it, pledging to educate the public about seismic
performance rating systems and how the information can be used, and announcing the
intention to use it or some similar system to rate all city-owned buildings.
Mandatory Screening
Screening programs help jurisdictions collect more information about targeted potentially
vulnerable buildings in a community, usually as a first step to later more stringent requirements
for the subset that are found to have features indicating significant deficiencies. With relatively
low cost and difficulty for owners, the jurisdiction can both make the issue visible and filter out
properties that do not meet the eligibility or targeting criteria, thereby reducing the
burdensome handling of errors and omission at a later stage. They also help jurisdictions
determine the overall scope of the problem—how many buildings exist that have certain risk
characteristics and how significant of a threat they pose in aggregate. This can help build the
case for further legislation.
30 The organization’s website is: www.usrc.org (Accessed April 13, 2016).
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For soft-story wood frame buildings, Oakland was a pioneer of the mandatory screening
approach. An inventory of multifamily apartment buildings was created in 2008 with the help of
volunteers and non-engineers under a contract with ABAG. This survey identified 24,273
residential units in 1,479 buildings with five or more units, between two and seven stories, built
prior to 1991, that had wide open spaces for parking or commercial uses on the ground floor
(ABAG, 2014). Spot testing suggested the list might have error rates that could potentially
undermine future program effectiveness, and might be politically unacceptable (personal
communication, Jeannie Perkins, 2008). Therefore, in 2009 the City passed ordinance Number
12966 which declared these buildings “potential soft-story buildings” and mandated submittal
of a Level 1 Screening–Non-Engineered Analysis. The screening had to be performed by a
registered design professional, licensed contractor or certified inspector, to provide some
assurance of accuracy regarding features that might related to risk. Anecdotally, the cost to
owners for this was generally around $200 to $500. This can be summarized as a rule-in
screening approach.
Persons involved with analyzing Oakland’s program (personal communication, Danielle
Hutchings-Mieler, 2011) concluded that many owners were confused, compliance was lower
than hoped, and exemptions may have been given without adequate quality control of the
reported data. This later contributed to the decision to incorporate mandatory evaluation
phase when the city of Oakland was ready to move towards a mandatory retrofit program. In
other words, a less than satisfactory implementation of a screening phase can slow down
progress towards and increase the effort required in future retrofit programming.
In its approach to soft-story wood frame buildings, San Francisco opted for a screening phase to
weed out obviously non-affected properties, for instance those misidentified as having the
correct number of units, stories, or first floor uses (primarily focusing on ruling out
inappropriately included properties). Similar to Oakland, the screening had to be performed by
a registered design professional, such as a licensed contractor, engineer, or architect.
Compliance in filing screening forms by the initial deadline was 98%, a success which was
helped by a suite of outreach activities including four waves of post card reminders, a retrofit
fair, a weekly updated website, an advisory group process, and multiple public meetings. The
compliance postcards used took advantage of real-time information sharing to “nudge” owners
to respond, such as mentioning how many other owners had already taken action by that point
(see Figure 6).
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Figure 6: Front and back of a compliance reminder postcard sent to affected owners in the City of San
Francisco’s soft-story wood frame program.
Mandatory Evaluation
In the 1980s, Palo Alto was an early innovator with the technique of requiring owners of certain
buildings in a community to file a formal engineering evaluation (Herman et. al., 1990). Because
a licensed engineer (or structural engineer) must perform this work, such evaluations are
approximately an order of magnitude more expensive than screenings. Evaluation costs for
soft-story wood frame buildings in Berkeley, for example, were approximately $2,000 to $5,000
(Rabinovici, 2012). However, evaluation costs may vary substantially for other building types
that are more difficult to assess, in other jurisdictions, and/or where evaluation requirements
are more extensive or complex.
Evaluation programs are costlier for jurisdictions to administrate than screening programs for a
variety of reasons, but provide several advantages. Jurisdictions typically give owners more
time to comply longer, owners need more guidance on how to comply, and there is increased
need for processing time and more qualified reviewer labor. In Berkeley, report review was
contracted out to plan checkers for a flat fee of $583 per evaluation report, and this did not
cover jurisdiction staff time.
On the benefits side, evaluations offer greater hope of achieving tangible risk reduction. As
noted, a remarkable one in four soft-story wood frame building owners voluntarily retrofit in
the wake of mandatory evaluation policy implementation in Berkeley, which meant over 2,000
of its residents now live in buildings that likely would not have been retrofitted otherwise.
Interviews with soft-story wood frame owners in Berkeley also showed that many considered
mandatory evaluation more fair than a voluntary retrofit program because it “leveled the
playing field” (Rabinovici, 2012). Rather than having retrofit practices in their community
determined ad hoc, all owners of similar properties were now being treated alike.
However, the benefits of mandatory evaluation are undeniably uncertain and dependent on
whether community circumstances are conducive to create a significant voluntary retrofit
effect (Figure 7).
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Figure 7: Graph showing a seven-fold increase in permit applications in the four years immediately
following passage of Berkeley’s 2005 mandatory evaluation law for soft-story wood frame buildings.
Mandatory Retrofit
Through California’s URM law, hospital, and school programs as well as soft-story wood frame
buildings at the local scale, there is clear precedent for imposing earthquake retrofit work to be
done for certain buildings. This is the most effective type of program for ensuring that on the
ground risk reduction will be done. As discussed in the Task 2 report, on average over four
times as many URM building cases have been retrofit in California in mandatory programs
(70%) compared to voluntary ones (16%). However, because mandatory programs require all
buildings to be addressed, owners with the most marginal properties cannot avoid taking
action, in some cases leading to higher demolition rates (Comerio, 1992). In the case of URM
buildings, mandatory retrofit programs did have higher demolition rates than voluntary
programs, 17% compared to 8% respectively (CSSC, Status of the Unreinforced Masonry
Building Law, 2006).
Depending on the program timeline, it may take years to decades for tangible risk reduction to
be realized. Retrofit projects naturally occur in steps, and can only be carried out as quickly as
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financing, contracting, any tenant relocation, or construction logistics allow. Thus, compliance
periods for mandatory retrofit programs need to be longer than for mandatory screening or
evaluation programs. For URM buildings, many jurisdictions tended to set deadlines of ten
years or more, followed by generous extensions. For soft-story wood frame programs,
jurisdictions have given owners one to three years for first steps such as appeals, hiring an
engineer, complete an acceptable engineering report, or submit a permit application and
retrofit plan. Following that, owners are typically given another one to three years to complete
construction (see Table 3), in part to secure financing, time to work around planned vacancies,
and for adequate design. Longer timelines or exemptions can be offered for complex buildings
that may require costlier or innovative engineering solutions (for instance, historic properties).
Again, this is where phasing or tiers can be helpful.
Another difficult aspect of retrofit programs (even voluntary ones) is that jurisdictions need to
set specific expectations for what constitutes an acceptable retrofit. Jurisdictions have handled
this in a variety of ways. Retrofit ordinances typically directly reference one or more particular
standards (or equivalent criteria). The table of soft-story wood frame programs (Table 3) shows
that five or more standards have been referenced recently and several jurisdictions reference
more than one, which can increase compliance ambiguity and the level of reviewer skill
required but also an engineer’s discretion to use the one most appropriate for their client’s
situation.
Also at issue is how much and how far a building’s vulnerabilities should be retrofit. For
instance, in the case of soft-story wood frame buildings, a retrofit can be designed to address
only the first story weaknesses, rather than all seismic vulnerabilities that are identified.
Jurisdictions such as San Francisco and Berkeley have chosen this route, in part because it
lessened political resistance to creating a mandate and addressed the most severe deficiencies.
Other deficiencies above the first story may remain and may lead to damage in an earthquake.
In the case of mandatory evaluation or retrofit programs, owners and their engineers will also
need guidance about how to prepare an acceptable evaluation, and how to submit a
concurrent retrofit permit application. Owners in Berkeley realized a major financial advantage
to paying their engineer to do both an evaluation for the jurisdiction and a full set of retrofit
plans at the same time (Rabinovici, 2012), so having clear retrofit standards in place already
was a major boon to those owners.
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The potentially negative effects on public safety and on owners of choosing a longer
compliance timeline should be noted. Earthquakes can occur at any time, so a program that
offers longer compliance windows in effect allows people in the community to spend more
time using and owning buildings that the jurisdiction has deemed unacceptable in the long run.
Also, real liability consequences may exist for owners that delay in doing mandated retrofit
work, even before an accepted compliance window has elapsed. A California Appellate court
awarded $2 million to family members of two women who died in a URM collapse in the 2003
San Simeon earthquake.31 In doing so, the court rejected the defendant’s claim that they had
no duty to retrofit the building until 2018, the deadline established by the San Louis Obispo
mandatory retrofit ordinance.
Incentives
To complement any of the above program formats, jurisdictions can offer either financing- or policy-
oriented incentives. Many ways exist to encourage and ease the path for owners to complete either
voluntary or required retrofit work, or even to help them submit timely screening forms or engineering
reports. Financial incentives and tools provide monetary assistance, either directly to an owner or via
the jurisdiction. Financial incentives include measures such as tax credits, tax rebates, grants, or fee
waivers that make a retrofit less expensive to complete. Financial tools (e.g., special low-interest
financing programs) provide a mechanism for an owner to obtain the necessary funding, potentially at
lower cost or paid back in ways other than for a traditional loan. Policy incentives are meant to
encourage private funding of mitigation, and include for example expedited review, exemptions,
development bonuses, or technical assistance. These measures offer owners indirect but potentially
valuable benefits as they take each mitigation steps.
Figure 8 provides a summary list of potential incentive types, while Appendix C gives details about
example uses, advantages, and disadvantages of each.
A group of agencies completed an inventory of jurisdiction incentive strategies using a survey of
California local governments in the mid-90s (ABAG, Seismic Retrofit Incentive Programs: A Handbook
for Local Governments, 1996). Though outdated and only 35% of contacted jurisdictions participated,
the report summarizes the types of URM and other earthquake programs that different jurisdictions
adopted and the kinds of assistance that owners could receive. The researchers also did interviews to
collect detailed information about fifteen illustrative cases at the time, including Palo Alto.
31See press coverage: http://calcoastnews.com/2010/06/court-finds-paso-robles-business-owners-liable-for-earthquake-
deaths/ Accessed April 13, 2016.
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FINANCIAL TOOLS AND INCENTIVES
(mechanisms that make financing
more accessible or directly reduce
project costs)
POLICY INCENTIVES
(mechanisms that deliver indirect
benefits to owners)
CO
S
T
A
N
D
I
M
P
L
E
M
E
N
T
A
T
I
O
N
D
I
F
F
I
C
U
L
T
Y
Hi
g
h
e
r
L
o
w
e
r
Waivers or Reductions of Building
Department Fees
Exemption from Future Retrofit
Requirements
Pass Through of Retrofit Costs to
Tenants (for jurisdictions with rent
control)
Expedited Permits, Inspections, and
Reviews
Property-Assessed Financing Loans
(PACE)
Exemptions or Relief from Standards
or Non-Conforming Conditions
Subsidized or Special Term Loans Condominium Conversion Assistance
Real Estate Transfer Tax Rebates Technical Assistance for Retrofit
Projects
Special District or Historic Designation
Tax Reductions
Zoning Incentives (e.g., relief from use
restrictions)
Tax Credits Transfer of Development Rights (TDR)
Grants Density or Intensity Bonuses (e.g.,
Floor Area Bonus)
General Obligation or Special Purpose
Bonds
Figure 8: Types of financial incentives and tools as well as policy incentives that have been used in local
earthquake risk reduction programs in California, in approximate order top to bottom from lowest to
highest cost and difficulty of implementation.
Several points stand out in the ABAG report regarding incentive use and effectiveness. First, most
jurisdictions offer a number of different incentives, rather than just one approach. This makes sense
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because building and owner circumstances vary widely; what may help one owner might be irrelevant
or inappropriate for another and vice versa. Second, jurisdictions have taken widely different
approaches with incentives, from offering almost nothing to offering substantial loans and grants.
Jurisdictions tend to come up with incentive offerings closely tailored to their own goals and
circumstances, based on economic conditions, building stock vulnerabilities, political will, and other
factors. As a result, there is no single best incentive package to offer.
Another key point is that creation and operation of incentive programs is intense and must be locally
customized. Extensive community education and involvement are required to assess needs, design and
advertise the incentive offerings, and to help owners take advantage of them. Guiding community
members through the mitigation process is time consuming and difficult, usually requiring at least one
full time staff member who also has to coordinate with staff across several departments. That means
the personalities, technical skills, and political savvy of the internal team will be critical, and likely
variable over time, due to natural staff and political turnover issues.
The effectiveness of different incentive approaches, individually or in packages, has not been
systematically studied. Both ABAG and the San Francisco CAPSS project have produced high level lists
of potential incentive tools (ABAG, 2014; Samant & Tobin, 2008) but do not specify which tools are
being used where and to what effect. Many listed approaches are rarely or no longer being used. All
the variety makes it difficult to draw overall conclusions as to which incentives have worked “best”
where and why.
3. IMPLICATIONS AND POTENTIAL POLICY DIRECTIONS FOR PALO ALTO
Palo Alto is a medium sized, compact city with a diverse population and vibrant local economy. Nested
in the heart of Silicon Valley, the cost of living and development pressures are high, and space for
growth is limited. A high degree of interconnectedness with surrounding communities and a dynamic
natural environment is also evident.
As a community, Palo Alto cannot ignore its proximity to several major faults and the fact that it has
many different vulnerable building types. The estimated losses in a major event are significant.
Fortunately, Palo Alto has a legacy of proactive policy leadership in addressing earthquake risks, and a
relatively high degree of citizen and local government capacity. The potential benefits from retrofitting
are large. City leaders, by investing this year in risk assessment and a policy development dialog, have
demonstrated their capability and will to act.
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This review found no simple best local earthquake mitigation policy model for Palo Alto to follow. Each
of the jurisdictions mentioned in this report has crafted, often over a decade or more, a unique
package of measures suited to their own local economic, social, political, and risk realities. Palo Alto
must do the same.
In developing its own strategy, Palo Alto can learn from this variety among local mitigation programs. It
can build on the successful framework of its own existing program while also combining and tailoring
new elements that are working for other jurisdictions.
Choosing Goals and Desired Outcomes
One way to measure success is in relation to program goals and resource realities. From that
standpoint, each of the programs mentioned in this report is successful to some degree.
Some jurisdictions set out to do what they could with limited resources, progressing only the first steps
of developing an earthquake mitigation program. The City of Richmond, for example, developed an
inventory, hosted a community meeting, and notified owners as part of creating a very low cost
voluntary approach to soft-story wood frame buildings. The good news is that by doing so, it achieved
meaningful progress relative to jurisdictions that have done nothing. Public leaders and the broader
community are more aware, city reputation and visibility have been enhanced, and city staff are now
better connected to a network of local earthquake professionals that can help facilitate future action if
and when that becomes possible. The bad news is that Richmond has been stymied so far by the
departure of key staff, limited jurisdictional resources, and the limited resources of its soft-story wood
frame building owners and tenants; a more aggressive retrofit program is not realistic until an outside
source of funding is found.
At the other extreme, a few leading jurisdictions set out to comprehensively assess earthquake
vulnerabilities and risk reduction opportunities community-wide through a lengthy, relatively
expensive, and collaboratively-informed processes. San Francisco and more recently Los Angeles are
the most prominent users of this approach, producing in-depth reports and resilience plans intended
to guide city efforts for decades. Importantly, these plans encompass many city activities and roles,
types of buildings and building uses, different phases of the disaster cycle, and explicitly seek to
connect earthquake mitigation efforts to a host of other community resilience concerns, from sea level
rise to water supply reliability to telecommunications operations (Several leading local program models
and planning resources for these types of efforts are introduced in Appendix D).
In between are jurisdictions where program goals are either narrower in scope with more vigorous
requirements (such as the City of Fremont’s mandatory retrofit program for soft-stories) or wider
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scope with less vigorous requirements (such as the City of Santa Monica, which mandates retrofits for
soft-story wood frame buildings and nonductile older concrete structures but only when triggered by a
substantial renovation).
The City of Berkeley took a phased, relatively aggressive approach to soft-stories, but has yet to put in
place a program to address the 50 or so tilt-up concrete structures it has identified. Oakland is also
somewhat unique in being a larger city that has mandated soft-story retrofits without initially taking a
comprehensive approach. However, both Berkeley and Oakland benefited first from substantial
volunteer professional involvement and later from sizeable, multi-year Rockefeller Foundation 100
Resilient Cities grants. Through the early help of both volunteers and consultants, Berkeley and
Oakland laid the groundwork for mandatory programs that likely helped to attract the additional
philanthropic attention and assistance. Berkeley has now produced, and Oakland is on its way to
producing, a comprehensive resilience assessment and plan similar to what was done by San Francisco
and Los Angeles.
In this light, Palo Alto is currently in the “middle” group in terms of its scope and requirements for
seismic safety compared to other leading jurisdictions. Palo Alto set new policy precedents in the
1980s with its community engagement, mandatory evaluation, and voluntary retrofit programs for
three different categories of structures. However, this only addressed a small subset of its overall
vulnerable building stock. By investing in data collection and community discussions this year, Palo Alto
is now poised to move forward into a new position of seismic policy leadership.
It is critical to first clarify community values and goals before designing a program to try to achieve
them. All stakeholders should be invited to participate in discussions of what matters most to the City
and the people who live, work, and invest in it. Common broad goals include increased public safety,
reduced private property damage, and reduced downtime and displacement of businesses, consumers,
and residents. However, addressing of different building types may advance these goals to different
degrees and with different levels of certainty and speed. For instance, addressing soft-story wood
frame housing may have little direct benefit for local businesses but would reduce renter
displacement. Retrofit of older concrete structures might address concerns about provision of basic
services after an event, but would have little or no benefit for housing.
If the goal is to achieve the greatest reduction in losses, Palo Alto should address building types known
to be potentially hazardous that occur in large numbers. Once community discussions lead to a sense
of priorities and preferences, trade-offs and alternatives for pursuing each goal can be understood and
considered.
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Wherever Palo Alto chooses to focus, it should strategically combine policy features to promote risk
reduction. As this report revealed, regardless of scope, the most effective programs use a package of
measures to tip the balance away from the status quo by publicizing and increasing the consequences
of not retrofitting while also publicizing, easing the costs, and increasing the benefits of retrofitting.
Potential Policy Directions
Coming out of this local program review is a list of alternative approaches for Palo Alto to consider:
Option 1: Status Quo
In this option, the existing ordinance with its mandatory evaluation, voluntary retrofit approach
remains in place without changes. This covers 89 buildings and has three categories: Category I—
unreinforced masonry (except for under 1,900 sf with 6 residents), Category II—built before 1/1/1935
with 100 or more occupants, and Category III—built before 8/1/1976 with 300 or more occupants. As
of 12/9/14, City records indicated that sixty-six of the buildings had been either retrofit, demolished,
planned to be demolished, or found exempt, while 23 remained unaddressed. Evaluation was
mandatory, and owner funded but retrofit is voluntary. The list is publically available by request, but
not advertised. Floor area ratio bonuses are (were) available.
Option 2: Increase Scope, but Retrofit Remains Voluntary
Additional categories of structures would be added to the mandatory evaluation requirements. Palo
Alto can consider programs for soft-story wood frame buildings, older concrete buildings, older tilt-up
buildings, and older steel moment frame buildings. Precedents exist for programs addressing each of
these structural types that pose well-identified, publicly important risks. Completion of an evaluation
report could be separated into different timelines, for instance three to ten years, depending on
degree of hazard. Palo Alto could also use location, occupancy type, and/or number of occupants as
criteria in defining the scope or compliance timelines.
Option 3: Similar to Option 2, but Additional Disclosure Measures are Incorporated
This option would be similar to Option 2, but the list of buildings and status could be prominently
posted on City website, tenants could be notified, signage could be required, and/or a recorded notice
could be added to the property title. These options enhance transparency with the public and reward
owners that retrofit by increasing the perceived benefits of retrofitting among potential tenants and
buyers. Relatively inexpensive measures like these have been shown to be effective in increasing public
awareness and motivating greater consideration of earthquake risk in private decisionmaking,
including voluntary retrofits.
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Option 4: Increase Scope, Some Categories are Voluntary and a Few Categories are Mandatory, with
Enforcement by Trigger Threshold
This option builds on Option 3, but retrofitting would be required for some building types at whenever
future time a building is sold or undergoes substantial renovation above a set threshold.
Option 5: Increase Scope, Some Categories are Voluntary and a Few Categories are Mandatory, with
Enforcement by a Fixed Timeline
This option would be similar to Option 4, but retrofitting is required according to a fixed timeline.
Timelines and enforcement emphasis could vary depending on tiers or priority groupings to motivate
prompt action for the most vulnerable or socially important structures. In some cases, longer time
frames are adopted for some building types such as older concrete, to ease the burden on owners and
allow for technical advancement in retrofit techniques.
Option 6: Similar to Option 5, but More Categories are Mandatory
This alternative is similar to Option 5, but retrofitting would be required for additional categories. Palo
Alto can also make its programs more stringent over time. Explicit phasing has been successful in
jurisdictions like Berkeley and San Francisco for generating political consensus and enhancing
administrative feasibility.
This array of options can be also be shown in diagram format (Figure 9), which shows how a number of
jurisdictions in this report have positioned themselves in terms of the relative strength of their
requirements and the number and scope of the building types addressed.
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Figure 9: Diagram showing alternative policy directions for Palo Alto in the context of other jurisdictional
earthquake mitigation programs.
When considering options, Palo Also leaders and community members should keep in mind the
following additional findings from this review:
Mandating retrofit is the surest way to achieve risk reduction.
Jurisdictions are increasingly using disclosure measures to motivate retrofits in both voluntary
and mandatory programs, and such approaches have been shown to be powerful and relatively
low cost to implement.
Many mandatory programs use intermediate mandatory screening and/or evaluation phases to
better gauge the risk and filter out properties that need not comply before implementing
retrofit requirements.
Fixed timelines allow a jurisdiction to prioritize and control the pace of risk reduction, provide a
predictable planning horizon for owners.
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Incentive Options and Considerations
By offering a strategic set of incentives and devoting a steady, adequate program budget, Palo Alto can
create a program that eases the financial and logistical burdens on owners and provides adequate
technical assistance to support retrofit project completion. Small incentives are meaningful and helpful
to owners, while larger incentives may be critical for a subset of owners that face particularly complex
or costly projects.
Palo Alto has several traits that could make policy incentives (non-monetary assistance) particularly
effective. One is a relatively manageable number of affected buildings for some building types. This
means city staff might be able to provide high quality assistance to owners in complying and taking
advantage of any special programs. Palo Alto is a highly desirable locale with a highly educated, real
estate savvy population, and robust real estate market. Palo Alto has experience using policy incentives
in the past, so staff and many owners are familiar with them.
Despite limited data on their use or effectiveness, incentives can be politically important and provide a
variety of benefits. Below are some specific ways incentives could play a role in Palo Alto’s future
program and some steps that Palo Alto can take to create a package of incentives effectively tailored to
its own goals and circumstances.
It is good to offer small incentives to all owners because it fosters positive interest in the
program and builds community good will. Modest incentives, on the order of a few
hundred dollars, help acknowledge the public value that is being created by the efforts
undertaken by owners. For example, offering fee waivers is a gesture that owners will
appreciate, if not expect. Expedited permitting is likely to be viewed similarly, because time
equates with money. Policy incentives tend to be in the direct control of the City to
implement, and are often cost-effective and very helpful for owners in smoothing the path
and easing the hassle of doing retrofit work.
Incentives are especially important to the outcomes of voluntary programs. Incentives
play slightly different roles in mandatory compared to voluntary programs. In the case of
mandated upgrades, incentives essentially ease the burden of doing what has to be done or
to make it happen more quickly. In the case of, voluntary programs, the goal of incentives is
to motivate retrofit work to occur that might not have otherwise. In this way, incentive
offerings are more critical to the degree of risk reduction achieved in the case of voluntary
programs, and to political viability, perceptions of program fairness, and speed of risk
reduction achieved in the case of mandatory programs. Bottom line, in the case of URMs, a
small number of voluntary programs with substantial incentives have achieved similar
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success compared to mandatory programs. With soft-story wood frame buildings, voluntary
programs in the absence of incentives alone have not been enough to motivate retrofit
work to be done. An exception is for owners in financial hardship, where incentives are
most meaningful in mandatory programs.
Design the incentive strategy to match the circumstances of the locally targeted building
stock. FAR bonuses are likely irrelevant for soft-story wood frame buildings which are
seldom renovated to include more units or changes of use, but relaxing of parking
requirements or special provisions for condominiums may help. Mixed-used and historic
buildings may require deeper financial assistance when they face high costs associated with
retrofitting due to complex design issues, ADA compliance, and imposed restrictions on
changes in use.
Take time to assess actual need for incentives and the types that will make the most
difference to affected Palo Alto owners. Larger policy incentives like FAR bonuses can be
very effective, especially in higher income, higher growth communities like Palo Alto. In
contrast, larger financial incentives can be difficult to orchestrate and have not always been
as necessary or useful as hoped. Surprisingly, jurisdictions have sometimes found they have
to “sell” incentives programs to owners. Certain strategies tend to be very challenging and
costly to get the incentive to work compared to the amount of good they seem to do. Such
may be the case with PACE financing,32 as seen through the experiences of San Francisco
and Berkeley for soft-story wood frame buildings. When private market capital is
affordable, loan programs may not be needed or utilized. Use of larger, more complex
incentive instruments in general increases the amount of hand holding that is needed and
the amount of time until retrofits are completed.
Consider offering larger incentives to only those owners or properties that qualify or meet
certain social importance or hardship criteria. Interviews in Berkeley (Rabinovici 2012)
showed that soft-story wood frame building owners were open to the possibility of need-
based financial help. They did not want financing programs to reward ignorance or risky
business practices, but as long as the criteria are clear and the process is fair and
transparent, many expressed support for programs that would help fellow owners that are
truly burdened or in need. There was also support for using social or resilience importance
as part of the criteria for special financing eligibility.
32 Information about San Francisco’s PACE program can be found at: http://www.sfgov.org/esip/seismic-retrofit-financing
Accessed April 11, 2016. Information about Berkeley’s PACE programs can be found at: http://www.ci.berkeley.ca.us/PACE/
(Accessed May 2, 2016.)
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Integrate incentives as seamlessly as possible into the overall compliance process.
Incentives work best when they are delivered in a timely way, right when people are already
making important property or financial decisions. One notable example is the City of
Berkeley’s transfer tax rebate for single family home seismic improvements, which is
available retroactively two years before through two years after time of sale. Another is
Palo Alto’s floor area ratio (FAR) bonus for retrofit of designated vulnerable structures,
which allowed owners the chance to plan in additional space at the same time a retrofit is
being designed.
Beyond money, it will be important to offer technical assistance, and this can be very
helpful and even critical for some owners and engineers. Retrofitting is not a simple
process, and ironically it can become even harder for an owner if it happens as part of a
jurisdictional program that requires or is intended to encourage it. Obtaining financing,
especially through special programs, may also require intense staff effort.
Beware of the timing and costs of seeking public support for new bond financing. In
Berkeley, attempts were made to make a pool of funds available to owners through a
transfer tax increase measure on the November 2002 ballot, but it failed to get the required
two thirds vote. Participants in retrospect considered the campaign poorly run, but the
state of the local economy probably played more of a role than any decrease in support for
mandatory retrofit in concept.
Consider creation of formal cost-sharing arrangements between tenants and owners. Part
of the financial equation surrounding any upgrade work is the owner’s ability to capitalize
on the value added to the structure. In the case of rent control, the rate for pass through of
capital improvements is a matter of law. Jurisdictions like Oakland, Berkeley, and San
Francisco have negotiated cost-sharing arrangements ranging from 50 to 100% that allow
owners to increase rents up to a certain percent of the retrofit cost, over a specified time
period (usually 10 years). Even though Palo Alto does not have a rent control ordinance, it
could establish a permitted amortization schedule into any new retrofit law, which could
lessen the impact for tenants of any resulting rent increases.
Disclosure Measure Options
With relatively modest expense for a jurisdiction, disclosure measures can inform the populace and
leverage social and market awareness to amplify program effectiveness. In effect, signage, tenant
notification, internet lists, and other disclosure tactics make more transparent both useful risk
information and the policies a city is using to address risk.
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Public perception of disclosure policies has been on balance positive but not without critique. On the
one hand, revealing property addresses that are subject to an ordinance can be thought of as making
more accessible information that is already public. It spares all parties of going through the time and
hassle of formal information requests. It is also consistent with a philosophy of the public’s right to
know, and may be legally protective for both owners and jurisdictions against accusations that
important risk information is being held back. On the other hand, the media has at times portrayed
signage as a shaming device, though this may depend on a sign or placard’s particular graphic design
and wording. Soft-story wood frame owners in Berkeley described the overall suite of disclosure
measures imposed there as a “scarlet letter.”
San Francisco included disclosure practices as part of its first “nudging” phase in their program plan. In
essence, before and in complement to implementing mandates, San Francisco’s plan called for trying
to increase understanding in the real estate market empower tenants, buyers, and even owners (who
could now more credibly and prominently claim credit for early compliance, retrofitting ahead of
schedule, or voluntarily taking extra steps).
Evidence about the effectiveness of disclosure, either together with other policy requirements or
separately, is quite limited. In at least one case, voluntary retrofit programs combined with disclosure
measures have achieved significant risk reduction. Berkeley’s mandatory soft-story evaluation program
had several prominent disclosure features and resulted in a 25% voluntary retrofit rate in the first four
years (Rabinovici, 2012).
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4. REFERENCES AND RESOURCES
ABAG. (1996). Seismic Retrofit Incentive Programs: A Handbook for Local Governments.
ABAG. (1999). Preventing the Nightmare. Oakland, CA.
ABAG. (2014). Soft-Story Housing Improvement Plan for the Cit of Oakland. Oakland. Retrieved from
http://resilience.abag.ca.gov/wp-content/documents/OaklandSoftStoryReport_102914.pdf
ATC. (2010). Here Today—Here Tomorrow: The Road to Earthquake Resilience in San Francisco. Community
Action Plan for Seismic Safety, Redwood City. Retrieved from
http://sfgov.org/esip/sites/default/files/FileCenter/Documents/9757-atc522.pdf
ATC. (2012). ATC 78-1: Evaluation of the Methodology to Select and Prioritize Collapse Indicators in Older
Concrete Buildings. Redwood City, CA.
Bonowitz, D. (2012). Soft-Story Risk Reduction: Lessons from the Berkeley Data. EERI, Oakland, CA.
Bonowitz, D., & Rabinovici, S. (2012). Soft-Story Risk Reduction: Lessons from the Berkeley Data. EERI, Oakland,
CA.
Chakos, A. P. (2002). Making It Work in Berkeley: Investing in Community Sustainability. Natural Hazards Review,
3(2), 55-67.
City of Los Angeles. (2015). Resilience by Design. Los Angeles.
Comerio, M. (1992). Impacts of the Los Angeles Retrofit Ordinance on Residential Buildings. Earthquake Spectra,
8(1), 9-94.
Concrete Coalition. (2011). The Concrete Coalition and the California Inventory Project: An Estimate of the
Number of Pre-1980 Concrete Buildings in the State.
CSSC. (2005). Homeowner’s Guide to Earthquake Safety . Sacramento, CA.
CSSC. (2006). Status of the Unreinforced Masonry Building Law. California Seismic Safety Commission,
Sacramento.
FEMA. (2009). Unreinforced Masonry Buildings and Earthquakes: Developing Successful Risk Reduction
Programs.
Herman, F., Russell, J., Scott, S., & Sharpe, R. (1990). Earthquake Hazard Identification and Voluntary Mitigation:
Palo Alto's City Ordinance. California Seismic Safety Commission 90-05, Sacramento, CA.
NIST. (2015). Community Resilience Planning Guide Volume 1. National Institute of Building Sciences. Retrieved
from http://www.nist.gov/el/resilience/upload/NIST-SP-1190v1.pdf
Olson, R. S. (1999). Some Buildings Just Can't Dance: Politics, Life Safety, and Disaster. Stamford, CN : Jai Press
Inc.
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Rabinovici, S. (2012). Motivating Private Behavior with Public Programs: Insights from a Local Earthquake
Mitigation Ordinance. Berkeley, CA: University of California Berkeley.
Samant, L., & Tobin, T. (2008). Memo to the Advisory Committee on Incentives to Encourage Seismic Retrofits:
Options for San Francisco”. San Francisco, CA. 5 Sept. 2008. San Francisco, CA: Community Action Plan
for Seismic Safety.
SF ESIP. (2011). Community Action Plan for Seismic Safety, San Francisco Earthquake Implementation Plan (ESIP)
Workplan 2012-2042. San Francisco, CA.
SPUR. (2008). The Resilient City: Defining What San Francisco Needs from Its Urban Resilience Strategy. San
Francisco, CA.
SPUR. (2011). Safe Enough to Stay: What will it take for San Franciscans to live safely in their homes after an
earthquake? San Francisco, CA.
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CHAPTER IV.
BUILDING INVENTORY FOR LOSS ESTIMATE
One of the first steps in the study was to develop a digital inventory of buildings in Palo Alto that
includes all the information necessary to build the exposure model for the loss estimate. Information
sources used to develop the inventory included county tax assessor files, City GIS files, a survey done
by the Palo Alto Fire Department and San Jose State University of soft-story wood frame buildings, field
notes from the building department files of selected buildings when the 1986 ordinance was being
developed, Google Earth and Street View visual reviews, and an extensive sidewalk survey.
The Santa Clara County tax assessor’s files, which included 21,187 parcels of real estate in the City of
Palo Alto, were used as a starting point to develop the building inventory. The 15,198 parcels
designated as single family or two-family residences were first removed, as these were excluded from
the study, leaving 5,989 parcels of interest. A parcel is not always equivalent to a building. On one
hand, there are some sites where there is one owner and one tax parcel, but there are multiple
buildings. Sometimes, it is easy to distinguish the separate buildings from an application like Google
Earth or Street View as there is sufficient separation between the structures; in other cases, a field
survey is needed when the seismic separation is small (or not present). On the other hand,
condominiums can be a single structure, but have multiple owners and thus multiple separate
taxpayers and parcel numbers. For the 3,630 residential parcels with three or more units, we found
1,324 distinct buildings. Of the remaining 5,989 – 3,630 = 2,359 tax parcels, we found that 961 tax
parcels were identified as “possessory interest.” They are used at the city-owned Palo Alto airport for
administration of property taxes for concessionaires and for other purposes at other locations in the
city, and they do not represent buildings. When they were removed, there were 1,398 non-residential
buildings. They were combined with the 1,324 residential buildings for a total of 2,722 buildings.
The assessor’s data typically included parcel number (APN), year built, occupancy type, square footage,
and number of stories. These data were supplemented with ArcGIS shape files of building and parcel
outline from City GIS files, providing the geospatial location of each parcel (by latitude/longitude).
In addition to this information, the exposure model requires basic data on structural system needed to
classify each building into a Hazus Model Building Type. For some buildings, this information was
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available from earlier inventory efforts, including a select set of inventory forms used in developing the
current seismic mitigation program, and a survey by SJSU and the City’s Fire Department of soft-story
wood frame buildings. However, for many buildings no structural system could be assigned based on
available records.
The field survey was used to assign the seismic force-resisting system (using the basic FEMA Model
Building Type classification system), and to confirm and supplement information acquired from the
digital files for number of stories, occupancy (using the Hazus occupancy categories), building area, and
year built. In addition, buildings were surveyed for vertical and plan irregularities.
After the sidewalk surveys and additional quality assurance refinements, we identified a total of 2,632
buildings in the study group for Palo Alto. This included 66 buildings subject to Palo Alto’s current
seismic mitigation ordinance, because 23 of the original 89 buildings subject to the ordinance have
been demolished.
Not all buildings were field surveyed and not all key attributes needed for loss estimation were
available for all buildings. For buildings that were not surveyed and were missing information, the
missing attributes were developed using statistical comparisons with buildings that were surveyed on a
sector by sector basis. A multi-step procedure was developed to fill in other missing attributes based
on the best available comparative information. For example, buildings with missing occupancy and
number of stories were assigned occupancies and number of stories with the same distribution of
occupancies for surveyed buildings in that sector. For buildings with missing square footage data, the
median values in the sector for residential and non-residential buildings were used. In assigning
missing seismic force-resisting system information and year built, some rules were applied based on
typical building practices. As a result, while the information for buildings that were not surveyed may
not be fully accurate at the individual building level, the overall data set is seen as sufficiently
representative for the type of loss estimates used in the project and relative comparisons made
between different building types that are discussed ahead.
In addition to the information discussed above, a replacement cost had to be established for each
building. Standard 2014 RS Means Replacement Cost values included in the loss estimation software
(Hazus) used were reviewed as a starting point, but not considered representative for Palo Alto. R+C
and Vanir Construction Management prepared adjustments to RS Means values to capture 2016 data
and local factors. These were reviewed by a task group of the City’s project Advisory Group that
included local design professionals and developers familiar with the local cost climate. The group
recommended an increase of the values in general, and identified target values for selected common
occupancies. Based on these recommendations, R+C updated the values and Vanir reviewed them and
revised the non-targeted occupancies for estimating consistency. The resulting replacement costs are
shown in Table 5, and were used in the loss calculations. It is noted that resulting costs are 1.7-2.6
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times the RS Means-based Hazus default values (2014 cost data), and that costs are intended to be
representative of averages across the town.
Table 5: Average $/SF replacement building cost by Hazus occupancy class.
Occupancy Class RS
Means
2014
Average
Palo
Alto
Cost1
[$/SF]
Market
Factor
for
Palo
Alto
Escalation
Factor
from 2014
costs to
2016 costs
Demo &
Minimal
Sitework
(5’
around
building)
[$/SF]
Soft Cost
Premium2
Average
2016
Palo
Alto
Cost w/
Soft
Costs
[$/SF]
Multiplier
(Replaced
with Soft
Costs / RS
Means)
Multi Family, duplex $130.75 40% 10% $17.50 20% $263 2.01
Multi Family,
triplex/quad
$114.94 40% 10% $17.50 20% $233 2.03
Multi Family, 5-9 units $206.41 40% 10% $17.50 20% $402 1.95
Multi Family, 10-19
units
$194.12 40% 10% $17.50 20% $380 1.96
Multi Family, 20-49
units
$212.26 40% 10% $17.50 20% $413 1.95
Multi Family, 50+ units $199.90 40% 10% $17.50 20% $390 1.95
Temporary Lodging $217.83 40% 10% $17.50 20% $424 1.94
Institutional Dormitory $234.44 50% 14% $25.00 20% $511 2.18
Nursing Homes $238.07 50% 12% $25.00 20% $510 2.14
Retail Trade $121.66 80% 10% $17.50 20% $310 2.55
Wholesale Trade $118.13 60% 10% $17.50 20% $$270 2.29
Personal & Repair
Services
$143.47 60% 10% $17.50 20% $324 2.26
Professional/Technical/
Business Services
$194.52 65% 12% $17.50 20% $452 2.33
Banks $281.88 40% 12% $25.00 20% $560 1.99
Hospitals $372.59 50% 14% $35.00 20% $807 2.16
Medical Office/Clinics $267.85 20% 10% $17.50 20% $445 1.66
Entertainment/Recreation $248.61 25% 12% $25.00 20% $448 1.80
Theaters $186.45 35% 12% $25.00 20% $368 1.98
Parking $84.59 20% 10% $17.50 20% $155 1.83
Heavy $144.71 25% 10% $17.50 20% $260 1.80
Light $118.13 25% 10% $17.50 20% $216 1.83
Food/Drugs/Chemicals $229.48 30% 12% $17.50 20% $422 1.84
Metal/Minerals
Processing
$229.48 30% 12% $17.50 20% $422 1.84
High Technology $229.48 40% 14% $17.50 20% $461 2.01
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Table 5: Average $/SF replacement building cost by Hazus occupancy class.
Occupancy Class RS
Means
2014
Average
Palo
Alto
Cost1
[$/SF]
Market
Factor
for
Palo
Alto
Escalation
Factor
from 2014
costs to
2016 costs
Demo &
Minimal
Sitework
(5’
around
building)
[$/SF]
Soft Cost
Premium2
Average
2016
Palo
Alto
Cost w/
Soft
Costs
[$/SF]
Multiplier
(Replaced
with Soft
Costs / RS
Means)
Construction $118.13 30% 10% $17.50 20% $224 1.89
Church $118.13 50% 12% $25.00 20% $268 2.27
Agriculture $199.08 10% 12% $17.50 20% $315 1.58
General Services $152.63 40% 10% $17.50 35% $341 2.23
Emergency Response $259.52 40% 14% $25.00 35% $593 2.28
Schools/Libraries $193.00 40% 12% $25.00 35% $442 2.29
Colleges/Universities $214.91 60% 12% $25.00 35% $554 2.58
Notes:
1. RS Means average cost includes RS Means default location factors to adjust national average to Palo Alto of 15%
for residential and 11% for commercial.
2. Soft costs include architect and engineer design fees, testing and inspection, utility connection fee, permits, and an
allowance for owner change order contingency.
3. Costs are intended to be representative of average in Palo Alto across the town, including downtown areas together
with other areas in the city.
4. Costs were previously prepared following a 3/7/2016 discussion with the Palo Alto Seismic Risk Program Advisory
Group Technical Advisory Committee. Table includes minor updates based on internal review between Rutherford
+ Chekene and Vanir Construction Management to achieve improved relative ratios between different occupancy
types.
Table 6 shows how the number and aggregate value of Palo Alto’s buildings is distributed by structural
system, using the FEMA Model Building Type classification system for structural system. The table is
sorted by aggregate building value. Wood frame buildings make up about 60% of the number of
buildings, and represent 35% of the total value. About 20% of the buildings are concrete, and they
represent over 40% of the total value. Of the remaining 20%, about two-thirds are masonry buildings,
and one-third steel. However, the steel buildings represent about twice the value of the masonry
buildings.
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Table 6: Distribution of number of buildings, building area, and building value by Model Building
Type.
Model Building Type Number of
Buildings
Aggregate Square
Feet (1,000)
Aggregate Building
Value ($M)
Concrete shear wall (C2) 318 9,699 4,082
Concrete tilt-up (PC1) 242 8,054 3,368
Wood frame larger residential (W1A) 331 8,403 3,232
Wood frame commercial/industrial (W2) 307 6,209 2,369
Steel braced frame (S2) 50 3,116 1,391
Wood frame smaller residential (W1) 898 3,821 1,278
Steel moment frame (S1) 75 3,005 1,242
Reinforced masonry, wood floor (RM1) 285 2,806 1,209
Reinforced masonry, concrete floor (RM2) 30 574 211
Steel light metal frame (S3) 41 533 177
Precast concrete frame (PC2) 5 334 125
Concrete moment frame (C1) 18 325 117
Steel frame with concrete shear walls (S4) 13 162 72
Unreinforced masonry bearing wall (URM) 9 274 15
Concrete with masonry infill (C3) 8 26 8
Steel frame with masonry infill (S5) 2 6 3
Totals 2,632 47,346 18,899
The study group can be further divided into age groups separated by significant milestones in building
code implementation. The following age groups were selected: pre-1927, 1927-1961, 1962-1976, 1977-
1997, and 1998 until now. The milestones reflected include the first earthquake code in Palo Alto in
1926, adoption of the 1961 Uniform Building Code (UBC) and associated higher forces, code changes in
the 1976 UBC following the 1971 San Fernando Earthquake, and code changes in the 1998 UBC
following the 1994 Northridge Earthquake. Figure 10 shows a histogram of the year built of the
buildings in the study group.
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Figure 10: Distribution of year built of buildings in study group with significant changes in the building
design practice.
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CHAPTER V.
VULNERABLE BUILDING CATEGORIES
One of the important tasks in the risk assessment study was to identify potentially vulnerable building
categories specific to Palo Alto using the building inventory that was developed early in the risk
assessment study. Potentially vulnerable structural system types were identified based on experience
in past earthquake events, knowledge of milestones when improvements in seismic code requirements
were made in Palo Alto, rankings in prominent seismic risk assessment tools such as the 2015 edition
of FEMA P-154 Rapid Visual Screening of Buildings for Potential Seismic Hazards, results from past
seismic risk assessment studies in California communities, and engineering judgment. The building
categories were then evaluated in analytical loss estimate studies described ahead which helped to
confirm the selected categories as appropriate for Palo Alto. Key building vulnerability metrics include
the risk of deaths and injuries, the cost of damage, and the extent of downtime or loss of use. Buildings
in the identified vulnerable building categories tend to perform poorly with respect to all three of
these metrics though the relative degree of vulnerability to each factor varies.
Community resilience is improved if residents have homes that remain usable after an earthquake
event, and if businesses can still operate. From a program perspective, the consultant team and
Advisory Group believe the greatest reduction in losses and the largest benefit to community resilience
will come from seismically retrofitting building types know to be both potentially hazardous and
present in significant numbers in Palo Alto.
In addition to the three categories already in Palo Alto’s seismic hazard identification ordinance
(Categories I, II, and III below), five additional categories of vulnerable building types were identified.
All five categories meet the criteria of being potentially hazardous and having a significant presence in
Palo Alto. The eight categories and the approximate number of buildings included in each category are
as follows:
Category I: Constructed of unreinforced masonry, except for those small than 1,900 square feet
with six or few occupants (10 remaining buildings in Palo Alto);
Category II: Constructed prior to January 1, 1935 containing 100 or more occupants (4
remaining buildings);
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Category III: Constructed prior to August 1, 1976 containing 300 or more occupants (9
remaining buildings);
Category IV: Pre-1977 soft-story wood frame (294 buildings);
Category V: Pre-1998 tilt-up concrete (99 buildings);
Category VI: Pre-1977 concrete soft-story (37 buildings);
Category VII: Pre-1998 steel moment frame (35 buildings);
Category VIII: Other pre-1977 concrete construction (170 buildings).
The loss estimate discussed ahead in Chapter VIII confirmed that the potential reduction in losses from
retrofitting is significant for these categories.
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CHAPTER VI.
CONCEPTUAL SEISMIC RETROFITTING OF REPRESENTATIVE
VULNERABLE BUILDINGS
Retrofit was considered for all buildings that have not already been retrofitted and were either
constructed before 1961 or between 1962 and the “benchmark” year with a soft story. A “benchmark”
year is when the code requirements for that building type became similar to those currently in place.
Buildings built after a benchmark year are assumed not to have significant seismic deficiencies and are
typically not seismically retrofitted. Consistent with typical practice, the performance of the retrofitted
buildings in an earthquake is assumed to be less than that of newly constructed buildings.
For estimating the cost of retrofit for the improved buildings, Rutherford + Chekene developed
conceptual designs for Model Building Types that represent a significant number and value of Palo
Alto’s building stock, as well as a significant loss and loss reduction after retrofit. This process identified
wood frame (W1, W1A, W2), steel moment frame (S1), concrete shear wall (C2), concrete tilt-up (PC1),
and reinforced masonry (RM1) and unreinforced masonry (URM) as appropriate candidates. For each
Model Building Type, the age, square footage and number of stories were reviewed to identify a
“prototype” building. In cases where the prototype building was not representative of more than two-
thirds of the total number of buildings, it was judged that multiple prototypes should be considered.
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Figure 11: Retrofit scheme for Large Multi-family Soft-Story Wood Frame Building.
For example, for the W1A Model Building Type there were a significant number of two-story and three-
story buildings with a significant difference in average square footage. Therefore, a two-story and a
three-story prototype building were developed to represent this Model Building Type. Eventually this
led to the 12 prototype buildings shown in Table 7.
Based on a review of buildings of size similar to the prototypes, representative floor plans were
developed. A conceptual retrofit was then shown on the floor plans. An example of a conceptual
retrofit for the W1A prototype building is shown in Figure 11 from a 2000 brochure by Rutherford +
Chekene for the City of San Jose entitled “Practical Solutions for Improving the Seismic Performance of
Buildings with Tuckunder Parking.” The retrofit elements were keyed to representative details in 2006
FEMA 547 Techniques for the Seismic Rehabilitation of Existing Buildings, and a written description of
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collateral impacts was developed as well to provide sufficient detail to allow a rough order of
magnitude cost estimate to be prepared. The conceptual retrofit designs, description of collateral
impacts, and referenced details are included in Appendix E.
The cost estimators of Vanir Construction Management used the conceptual designs to estimate a
range of probable cost to implement the retrofits. The retrofit costs for each prototype building are
shown in Table 7. These costs include hard costs, which are the costs the owner pays the contractor,
plus a design contingency as these are conceptual retrofits. The estimate further includes soft costs,
representing architect and engineer design fees, testing and inspection costs, permit fees, and an
owner change order contingency.
Considered costs do not include hazardous material abatement, costs associated with performing the
work while occupants are using the building, triggered accessibility upgrades, cost premiums
associated with retrofit of a historic building, tenant relocation or business interruption during
construction, project management, renovation, financing, repair of existing conditions, and legal fees.
These costs are more variable and project and site specific, and are typically not included in loss
estimates for this type of study. A detailed breakdown of estimated cost is included in Appendix F
The retrofit costs were extrapolated to Model Building Types not represented by a prototype retrofit
as shown in the fifth column of Table 7.
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Table 7: Conceptual retrofit cost.
Retrofit
Prototype
Model Building Type Stories Square
Feet
Used for
Model
Building
Types
Used
for
Square
Feet
Average
Retrofit
Cost
($/SF)
1 Wood frame smaller
residential (W1)
2 5,320 W1 All 12
2 Wood frame larger
residential (W1A)
2 9,500 W1A < 15,000 11
3 Wood frame larger
residential (W1A)
3 30,000 W1A ≥ 15,000 6
4 Wood frame
commercial/industrial (W2)
2 10,000 W2 All 14
5 Steel moment frame (S1) 2 43,900 S1, S2, S3 All 10
6 Concrete shear wall (C2) 1 5,000 C1, C2, S4,
PC2
< 10,000 50
7 Concrete shear wall (C2) 2 17,280 C1, C2, S4,
PC2
≥ 10,000 40
8 Concrete tilt-up (PC1) 1 18,435 PC1 < 25,000 29
9 Concrete tilt-up (PC1) 2 38,400 PC1 ≥ 25,000 21
10 Reinforced masonry, wood
floor (RM1)
1 2,750 RM1, RM2 < 5,000 74
11 Reinforced masonry, wood
floor (RM1)
2 8,150 RM1, RM2 ≥ 5,000 46
12 Unreinforced masonry
bearing wall (URM)
1 5,000 URM, S5,
C3
All 110
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CHAPTER VII.
LOSS ESTIMATING FINDINGS FOR EXISTING BUILDING STOCK
Hazus is a geographic information system (GIS) based, standardized, nationally applicable multi-hazard
loss estimation methodology and software tool. It is used by local, state, and federal government
officials for preparedness, emergency response, and mitigation planning. FEMA has recently released
the latest version of Hazus (Hazus 3.1) which includes building inventory data reflecting 2010 census
data for residential structures and costs to 2014. Rather than using the embedded inventory data for
Palo Alto, which are estimated from census data, a detailed earthquake risk assessment of the
individual buildings in the study group was conducted using the Hazus Advanced Engineering Building
Module (AEBM).
Direct loss is calculated through a complex process in Hazus. In essence, the engine consists of a large
database of “fragility functions”. These fragility functions describe the probability of exceeding
threshold damage levels as a function of a seismic demand parameter. For example, spectral
displacement is linked to slight, moderate, extensive and complete damage states to describe the
performance of a structural system. The estimated level of damage for the level of ground shaking
under consideration is then used to assign the costs to repair or replace the damage to the building’s
structural and nonstructural systems and contents (the loss). Each Hazus fragility function represents a
combination of Model Building Type, number of stories, and seismic design level.
Analyses were conducted for two specific earthquake scenarios developed by the United States
Geological Survey (USGS), a major M7.9 San Andreas Fault event, and a strong M6.7 San Andreas Fault
event.
The USGS has developed a suite of ShakeMap earthquake scenarios for different faults around
California. In the San Francisco Bay Area, they include events of different magnitude on a number of
faults, such as various segments of the San Andreas Fault and the Hayward Fault. The largest scenario
is a M7.9 event on the San Andreas Fault which represents a repeat of the 1906 earthquake. In this
scenario, all four segments (Santa Cruz Mountains, Peninsula, North Coast, and Offshore) of the San
Andreas Fault are assumed to rupture. There is a M7.2 event on the Peninsula segment with an
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epicenter somewhat south of Palo Alto. In addition to the scenarios, a ShakeMap of the 1989 Loma
Prieta earthquake which had an epicenter southwest of Palo Alto is also available.
In reviewing the available scenarios, the repeat of the 1906 earthquake provided a desirable, easy to
communicate upper bound scenario. Since the 1989 Loma Prieta event did relatively little damage to
buildings in Palo Alto (though there was substantial damage to some of the older buildings at nearby
Stanford University), it was judged to be too small to provide meaningful information for policy choices
in Palo Alto. Most of the Hayward Fault scenarios also produce small to moderate shaking in Palo Alto.
Review of the M7.2 San Andreas scenario found that it produced relatively similar peak ground
acceleration and short period spectral accelerations to those of the M7.9 scenario. Tom Holzer, an
engineering geologist with the USGS, is a member of the project Advisory Group. With his help and the
ShakeMap team at USGS, two other scenarios were developed between the M7.2 scenario and the
Loma Prieta earthquake. These are a M6.9 scenario and a M6.7 scenario on the Peninsula segment of
the San Andreas with an epicenter directly adjacent to downtown Palo Alto.
In the end, the M6.7 scenario was selected in addition to the M7.9 scenario. The M6.7 scenario
provided values somewhat smaller than the M7.9 scenario event, values large enough to be
meaningful, and is a magnitude size commonly used in USGS communications. It also has a
substantially lower equivalent return period from the M7.9 scenario.
Contour plots for the short period spectral acceleration for the two M6.7 and M7.9 scenarios are
shown in Figure 12.
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Figure 12: Predicted short period spectral acceleration in vicinity of Palo Alto (city boundary shown) for
two selected San Andreas Fault scenarios.
Table 8 summarizes the total loss calculated by Hazus for the as-is condition for the two earthquake
scenarios. The results show that the estimated losses to Palo Alto buildings and contents in a M6.7
scenario will be significant, on the order of $1.2 billion. Though ground shaking in the M7.9 scenario is
only about 25% larger than it is in the M6.7 scenario, overall building and content losses double to $2.4
billion. Average building damage and content damage also approximately double with a M7.9 event.
The difference in the number of buildings that are heavily damaged with the larger earthquake is more
pronounced with a 12-fold increase from the M6.7 to the M7.9 scenarios. This is shown in the fourth
column of Table 8 as the number of buildings with a damage ratio exceeding 20%.
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Table 8: Total losses for study group in as-is condition.
Earthquake
Scenario
Building
Value1
($B)
Content
Value2
($B)
Number
of Bldgs
with
Damage
Ratio ≥
20%3
Estimated
Building
Damage4
($B)
Estimated
Content
Damage4
($B)
Total
Building
and
Content
Damage
($B)
M7.9 18.9 17.3 224 1.7 0.7 2.4
M6.7 18.9 17.3 19 0.8 0.4 1.2
Ratio of M7.9/M6.7 2 2 2
Notes:
1. Building value is the complete replacement cost for the building, and includes the
structure, architectural, mechanical, electrical, and plumbing components (e.g.,
ceilings and lighting).
2. Content value includes the complete replacement cost of furniture and equipment
that is not integral with the structure (e.g., computers and other supplies). They
are estimated as a percent of structure replacement value, dependent on
occupancy.
3. Damage ratio is defined as the cost of repairing damage divided by the
replacement cost of the building.
4. Estimated building and content damage cost is the cost associated with repair and
replacement of the building and its content.
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To put the loss from building damage in context, the average annual valuation of Palo Alto construction
permits was $400M between 2013 and 2016 (which represents a boom period). The total loss in a
major M7.9 earthquake represents more than four years’ worth of construction, and the total loss in a
strong M6.7 earthquake represents more than two years worth of construction.
It should be noted that these losses do not include the effects of lives lost and business disruption, or
the ripple effects in the local economy or real estate market, and that much of this loss will not be
insured.
Table 9 breaks out the estimated loss and damage ratio for various model building types, and it can be
seen that it depends on the metric used which building type is considered the poorest performer.
Looking at the total loss alone, concrete bearing wall buildings and commercial wood frame buildings
are responsible for the highest total loss. This tracks well with the earlier finding that these structural
systems are the most prevalent ones. If we look at the highest average building damage ratio instead,
buildings with unreinforced masonry bearing walls and unreinforced masonry infills are the most prone
to damage. However, not very many of them exist in Palo Alto, and as a result they do not represent
much of the aggregate loss. It is therefore important to look at multiple metrics when deciding which
buildings are the most vulnerable and significant to the community as a whole.
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Table 9: Top three vulnerable building types ranked by total loss, average damage ratio, and number
of severely damaged buildings.
Building Type Number
of
Buildings
Building
Value
($M)
M7.9 EQ
Total
Building
+ Content
Losses
($M)
M7.9
EQ
Average
Building
Damage
Ratio
M7.9
EQ
Number
of Bldgs
with
Damage
Ratio ≥
20%
Concrete shear wall (C2) 318 4,082 477 14% 75
Concrete tilt-up (PC1) 242 3,368 365 12% 32
Wood frame commercial/industrial (W2) 307 2,369 216 9% 9
Steel frame with masonry infill (S5) 2 3 1 38% 1
Unreinforced masonry bearing wall (URM) 9 15 4 29% 9
Concrete frame with masonry infill (C3) 8 8 2 29% 6
Concrete shear wall (C2) 318 4,082 477 14% 75
Concrete tilt-up (PC1) 242 3,368 365 12% 32
Steel moment frame (S1) 75 1,242 130 18% 27
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CHAPTER VIII.
LOSS ESTIMATING FINDINGS WITH BUILDINGS RETROFITTED
A second Hazus AEBM run was done assuming a retrofitted building stock. For this run, it was assumed
that a building would be retrofitted if it has not already been retrofitted and is either constructed
before 1961 or between 1962 and the benchmark year with a soft story. The Hazus model was rerun
with the updated fragilities simulating retrofit.
Table 10 shows the resulting total losses and damage ratios. Though total losses are still significant,
comparing the results of Table 10 with Table 8 shows a reduction in total loss of 45% for the M7.9
scenario, and 33% for the M6.7 scenario. In other words, aggregate loss to the community if all
considered properties were retrofit could be reduced by one third in a very plausible event and almost
halved in a much larger event.
Another important improvement is the reduction of the number of buildings with more than 20%
damage. The M7.9 scenario shows a reduction from 224 buildings to 6 buildings, meaning that the
probability of building collapse and resulting injuries and fatalities has become very low.
Finally, the damage and loss of the M7.9 scenario remain approximately two times the amount
sustained in the M6.7 scenario. This suggests that the retrofit has a similar impact for both levels of
ground shaking.
Table 10: Total losses after retrofitting.
Earthquake
Scenario
Building
Value
($B)
Content
Value
($B)
Estimated
Building
Damage
($B)
Number
of Bldgs
with
Damage
Ratio ≥
20%
Estimated
Content
Damage
($B)
Total
Building
&
Content
Damage
($B)
M7.9 18.9 17.3 0.9 6 0.5 1.3
M6.7 18.9 17.3 0.5 0 0.3 0.8
Ratio of M7.9/M6.7 2 - 2 2
Table 11 breaks out the reduction in total loss by model building type for the M7.9 scenario, and shows
the associated retrofit cost. The average reduction in loss varies by building type, with URM buildings
showing the highest reduction in loss after retrofit of 80%, and steel braced frames showing an 18%
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reduction at the low end. On average, the retrofit costs are on the order of the damage reduction for
this scenario, though by building type the average damage reduction (loss avoided) divided by retrofit
cost ranges from 0.14 for steel light frame buildings to almost eight for reinforced masonry buildings.
Wood frame and concrete buildings are responsible for the largest reduction in total loss, with wood
frame construction representing over 20% of the loss reduction, and concrete buildings over 50%.
It should be noted that the data in Table 11 also includes buildings that were not retrofitted. As a
result, further parsing of the data is needed to better understand which buildings are responsible for
the most loss, and those that can be improved more cost-effectively.
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Table 11: Comparison of retrofit benefits and costs by Model Building Type.
Model Building Type M7.9 EQ
Average
Damage
($/SF)
M7.9 EQ
Total
Damage
Reduction
($1,000)
Average
Damage
Reduction
($/SF)
Retrofit
Cost
($/SF)
Wood frame smaller residential (W1) 16 13,775 4 12
Wood frame larger residential (W1A) 25 61,317 7 6-11
Wood frame commercial/industrial (W2) 50 160,155 26 14
Steel moment frame (S1) 62 76,150 25 10
Steel braced frame (S2) 44 24,222 8 10
Steel light metal frame (S3) 108 38,163 72 10
Steel frame with concrete shear walls (S4) 101 11,118 69 40-50
Steel frame with masonry infill (S5) 247 695 121 110
Concrete moment frame (C1) 55 8,045 25 40-50
Concrete shear wall (C2) 70 336,574 35 40-50
Concrete frame with masonry infill (C3) 120 865 34 110
Concrete tilt-up (PC1) 68 218,491 27 21-29
Precast concrete frame (PC2) 21 0 0 21-29
Reinforced masonry, wood floor (RM1) 59 87,697 31 46-74
Reinforced masonry, concrete floor (RM2) 35 3,727 6 46-74
Unreinforced Masonry Bearing Wall (URM) 23 5,216 19 110
Totals 51 1,046,210 22
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Table 12 shows those buildings types that may be considered good candidates for a retrofit program.
Although representing only about 15% of the total inventory, these buildings are responsible for over
30% of the total loss. This is reflected in the considerably higher than average loss (fourth column of
Table 12). The benefit of retrofit is also considerable for this group of buildings, as they are responsible
for over 50% of the reduction in loss. Additionally, the cost to retrofit them is only a fraction of the
losses avoided in a major event, ranging from a third for the concrete buildings to a tenth for the steel
frames. Note that these values are based on conceptual retrofits. Actual retrofit costs for individual
buildings would vary substantially, and the steel moment frame benefit-to-cost ratio is higher than
expected by engineering judgment. This is caused in part by a comparatively low retrofit cost for this
Model Building Type.
Table 12: Comparison of benefits and costs by selected Model Building Type, date and
characteristics.
Model Building Type Number
of
Buildings
Total
SF
(1,000)
M7.9 EQ
Average
Loss by
Building
($/SF)
M7.9 EQ
Average
Loss
Avoided
by
Retrofit
($/SF)
Average
Cost to
Retrofit
($/SF)
(Average
Loss
Avoided)
/
(Average
Retrofit
Cost)
Pre-1977 wood frame soft-story
(W1, W1A, W2)
294 3,690 66 46 12 4
Pre-1998 tilt-up
(PC1)
99 3,078 106 71 23 3
Pre-1977 concrete soft-story
(C1, C2, C3)
37 842 149 108 42 3
Pre-1998 steel moment frame
(S1)
35 690 152 110 10 11
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CHAPTER IX.
REVIEW OF PAST SEISMIC RETROFITS
To gain a better understanding of the quality of the retrofits and identify relevant issues to updating
Palo Alto’s seismic risk mitigation program, a sample of the submitted engineering studies and building
retrofit drawings was reviewed.
Ten buildings were selected, so that their permit history could be reviewed and documents could be
retrieved from the archives of the Building Department. They were distributed over the three existing
hazardous buildings categories, and also included soft-story wood frame buildings. Records were
retrieved for four Category I buildings (to reflect the higher number of these), two Category II
buildings, two Category III buildings, and two soft-story wood frame buildings.
The City tracked permit numbers for the retrofit projects in their “hazardous buildings” database. Even
so, it proved difficult to retrieve associated documents. After careful review of the City’s records, some
archived documents showing structural modifications were retrieved. The type of documents available
varied from building to building. In about half of the cases, plans were available, and in the other half,
the documents consisted of calculations with sketches.
For one of the Category I buildings, plans showing a comprehensive retrofit were available. The 2001
California Building Code was referenced for seismic design. In a second case, the retrieved plans show
retrofit of a section of the building that appears to be intended to improve the original retrofit. It was
unclear if other sections of the building were improved in a similar fashion. In the third case, structural
calculations were provided. It is unclear what criteria were used, as the 1991 UCBC is used for certain
elements and the regular UBC seismic load calculations for global loading. The set of plans retrieved for
the last building is for a tenant improvement that appears to have been constructed a few years after
the original seismic retrofit. Interestingly, the structural engineer referenced the 1977 UBC as the
seismic design criteria. The building is identified on the plans as a concrete building, rather than a URM
building.
For the Category II buildings, in one case only the permit application worksheet was available; in the
other case there were detailed calculations and sketches (no construction documents). The permit
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application for the first building indicates that shear walls were added as part of a voluntary seismic
upgrade. The sketches for the second building indicated that the retrofit was designed to mitigate the
deficiencies identified in the evaluation report. It references both elements and loads from the earlier
study.
For the Category III buildings, it appears that in both cases the projects were driven by modifications or
additions to the existing building. Since no plans were archived, and the calculations could not be easily
followed, it was not clear if the existing building was fully evaluated and if all deficiencies found in the
original evaluation report were addressed.
In 2003, the Collaborative for Disaster Mitigation at San Jose State University completed an “Inventory
of Soft-First Story Multi-Family Dwellings in Santa Clara County”. According to the report the City of
Palo Alto had 130 soft-first story multi-family buildings including 1,263 residential units housing 3,158.
The list of addresses from the San Jose State University report was updated with information from the
City of Palo Alto Fire Department, and resulted in a reduced list of 108 addresses. According to this list,
which was included in a recent Staff Report to Palo Alto’s Policy and Services Committee33, six buildings
were improved voluntarily. Two sets of plans were retrieved and reviewed; in one case the plans
improved two buildings with the same plan as a mirror image. One of the permits was issued in 2006
and one in 2009. It appears that in both cases the buildings were of a more recent vintage, as plans
show that existing plywood shear walls are present. On both sets of plans design criteria were
referenced, with one building referring to the 2001 California Building Code, and one Appendix Chapter
A4 of the 2006 International Existing Building Code.
Review of the submitted engineering studies and building retrofit drawings identified the following
relevant needs for future seismic risk mitigation programs:
Clear identification of retrofit design intent, scope, and limitations, also for voluntary retrofits;
Identification of existing structural systems;
Decision on requirements for buildings that have had partial seismic retrofits completed, and
may have remaining seismic deficiencies.
33 Policy and Services Committee Staff Report 5293, Discussion of Updating the Seismic Safety Chapter of the Municipal
Code for Hazardous Buildings, December 9, 2014, available online at
https://www.cityofpaloalto.org/civicax/filebank/documents/44945 (accessed 12/21/2016)
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CHAPTER X.
ADDITIONAL RECOMMENDED PROGRAM FEATURES
In addition to expansion of the building categories included within the City’s seismic risk mitigation
program and refinement of disclosure measures and incentive options, a number of other program
features are recommended. They are described in the following:
Use the current inventory, taking note of its limitations: The inventory developed for the effort
to date involved use of digital information and field surveys. A complete field survey of all
buildings in Palo Alto was outside the scope of the project. However, the inventory that has
been developed is an excellent resource. The first step in any future ordinance will involve
notification of building owners that they may be subject to the requirements of the ordinance.
Those buildings that were field surveyed and fall within the scope of the ordinance can be
notified using the existing inventory. For the remaining buildings, additional field survey is
recommended. This would be a rapid visual assessment and could be conducted by City staff or
outside consultants.
Use an initial screening form phase: Typically, as part of the notification process, a screening
form of about one-page in length is sent, and the owner is required to have a design
professional, such as a structural engineer or architect, complete the form for a relatively
nominal cost to confirm whether or not the building actually is subject to the City’s ordinance.
Some buildings may appear from a rapid visual assessment to be one of the building categories
covered, but upon closer review they are exempt. This approach has been taken in many
communities in the past, and thus sample forms are available that can be easily tailored for
Palo Alto.
Clearly specify seismic evaluation and retrofit scope: The seismic evaluation (and retrofit)
methodology for each building category will need to be defined after the building categories
included in the updated ordinance are determined. Industry consensus standards exist and
cover the vulnerable building categories identified for Palo Alto. These include the 2015
International Existing Building Code (IEBC) and 2014 ASCE 41-13 Seismic Evaluation and Retrofit
of Existing Buildings. Both are currently being updated by groups of engineers and building
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officials. For soft-story wood frame buildings, there is also the 2012 FEMA P-807 Seismic
Evaluation and Retrofit of Multi-Unit Wood-Frame Buildings with Weak First Stories. For steel
moment frame buildings, there is also the 2000 FEMA 351 Recommended Seismic Evaluation
and Upgrade Criteria for Existing Welded Moment Resisting Steel Structures. ASCE 41 has three
tiers of evaluation: Tier 1, Tier 2, and Tier 3. Tier 1 is primarily a screening tool. As a minimum
standard, Tier 2 is recommended. Table 13 provides recommended evaluation and retrofit
standards.
Table 13: Recommended Evaluation and Retrofit Standards
Category Description Evaluation and Retrofit Standards
I Unreinforced masonry IEBC Appendix Chapter A1
II Built before 1/1/35 with 100
or more occupants
ASCE 41
III Built before 8/1/76 with 300
or more occupants
ASCE 41
IV Pre-1977 soft-story wood
frame
IEBC Appendix Chapter A4, ASCE 41, or FEMA P-807
V Pre-1998 tilt-up IEBC Appendix Chapter A2 and ASCE 41
VI Pre-1977 soft-story concrete ASCE 41
VII Pre-1998 steel moment
frame
ASCE 41, or FEMA 351
VIII Other pre-1977 concrete ASCE 41
Provide detailed evaluation report submittal requirements: Minimum submittal requirements
for evaluation reports will need to be defined. The above evaluation and retrofit standards
provide some guidance but a short clear set of requirements will be beneficial. This will include
such items as address, construction date, size, number of stories above and below grade,
owner, occupancy type, structural system type, the location and features of the primary
structural system, the extent of field review, material properties, the evaluation criteria and
methodology used, whether the structure meets the evaluation criteria, identified seismic
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deficiencies if it does not. The current ordinance requires identification of retrofit measures to
address seismic deficiencies. Even in a voluntary program, it is recommended that this be
continued to help owners, tenants, and the City better understand what is necessary to
mitigate the issues that exist.
Specify how past partial retrofits will be handled: In the past, some buildings have had partial
seismic retrofits where only selected portions of the seismic force-resisting system have been
upgraded, and some seismic deficiencies may still exist in these structures. If mandatory retrofit
requirements are implemented that provide for comprehensive retrofitting of the full seismic
load path, there may be buildings with previous partial retrofits that do not fully comply and
need remaining deficiencies to be addressed. This will be identified in the seismic evaluation
report.
Update both new and existing building permit submittal requirements: Review of City records
found that basic information such as the building structural system, date of construction, and
retrofit standard used (where applicable) are not readily available. It is recommended that
submittals for permit for both new buildings and existing building renovations require this
information. For structural systems, both the categorization found in ASCE 41 and the ASCE 7
Table 12.2-1 is recommended. This will allow the city to have a much better understanding of
its building stock and its expected performance in an earthquake.
Write a new ordinance or set of ordinances to update the program: After the Council has
provided direction and the above issues have been addressed, an updated ordinance will need
to formally be written. This can be done by City staff, but will likely benefit from the
involvement of an appropriately experienced structural engineering consultant.
Carefully address program management and interdepartmental coordination needs: To
successfully manage Palo Alto’s updated Seismic Risk Mitigation Program, an effective
management plan is needed so that progress is monitored by the City and community intent is
achieved. It will include a realistic list of information that can be easily input, summarized, and
tracked in digital records such as the submittal requirements recommended above and that can
be used to link the seismic risk program data to other digital records such as assessor files or
GIS systems; quality assurance procedures for checking information; clearly defined roles and
responsibilities; timelines and requirements for reporting of information internally and
externally; procedures for gathering, assessing and implementing community feedback and
suggestions; and links between the seismic risk mitigation program and activities that will occur
following an earthquake, such as postearthquake safety evaluation.
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Delineate department and key staff responsibilities: For Palo Alto’s updated Seismic Risk
Mitigation Program, City staff will be responsible for several categories of activities.. These will
include the basic activities such as managing the notification and inventory process, reviewing
evaluation reports and plan checking retrofit construction documents, and field inspections of
retrofit work. Less obvious activities will include evaluating requested exceptions to the
program or alternative means of compliance; managing feedback from design professionals,
owners, and the public; tying pre-earthquake retrofitting to post-earthquake safety evaluations
records; and managing post-earthquake safety evaluation, repair, and recovery plans.
Depending on the scale of the updated program, it is possible that addition staff members or
consultants will be needed to handle the work flow. The City may also benefit from an
appropriately experienced structural engineer to provide advice on technical and program
management issues, particularly as the program moves to final definition and then to initial
implementation. Later, as is done in some communities, it may be desirable to create volunteer
review boards of local structural engineers who review questions on the evaluation and retrofit
criteria and provide the city with technical opinions that staff can use.
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CHAPTER XI.
QUESTIONS TO GUIDE COUNCIL DELIBERATIONS AND POTENTIAL
ISSUES FOR FUTURE STUDY
1. QUESTIONS TO HELP GUIDE COUNCIL DELIBERATIONS
Preferred policy directions were developed with the Advisory Group and staff as discussed in Chapter I
and include expansion of the building categories currently covered by the City’s ordinance, movement
toward mandatory requirements for some categories, additional disclosure measures and use of
incentives to increase the effectiveness and likelihood of compliance and of success. To help the
Council in its deliberations, a series of questions are given here. They are similar to questions and
issues discussed by the Advisory Group.
1. Does the Council wish to expand the current seismic hazard program to cover more vulnerable
building categories?
2. If so, which of the building categories in Table 1 should be included? The Advisory Group proposed
that the existing Categories I-III, plus the Categories IV-VII, be included as follows. The categories
are:
a. Category I: Constructed of unreinforced masonry, except for those smaller than 1,900 square
feet with six or fewer occupants (in the current ordinance)
b. Category II: Constructed prior to January 1, 1935 containing 100 or more occupants (in the
current ordinance)
c. Category III: Constructed prior to August 1, 1976 containing 300 or more occupants (in the
current ordinance)
d. Category IV: Pre-1977 soft-story wood frame
e. Category V: Pre-1998 tilt-up concrete
f. Category VI: Pre-1977 concrete soft-story
g. Category VII: Pre-1998 steel moment frame
An eighth category (Category VIII other older nonductile concrete buildings) was discussed, but
because of the lack of inexpensive analytical methods for reliably identifying the worst of these
buildings, inclusion of this building category in an updated ordinance is not recommended at this
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time. Such buildings could be included in the future when the engineering community has
developed appropriate analytical methods.
3. In addition to mandatory initial evaluation requirements, should one or more of the categories of
buildings be subject to mandatory retrofit requirements? The Advisory Group had a consensus on
mandatory requirements for renovation for unreinforced masonry buildings and there was strong
support among many members for other categories such as soft-story wood frame buildings and tilt-
up buildings, particularly those with high occupancies.
4. Should the City develop a trigger mechanism based on sale or substantial renovation where seismic
retrofit is required? If so, which building categories should be subject to a trigger mechanism?
There was support among some Advisory Group members for a trigger mechanism for some building
categories, such as tilt-up industrial buildings, particularly those that are being converted to office
buildings and increasing the occupant load and thus exposure to seismic risk.
5. What public disclosure or notice measures of the need for retrofitting a building should be pursued?
The Advisory Group supported website listing and tenant notification, but there was low support for
placing notices on property titles or for signage or placing placards on the outside of buildings.
Other possibilities include encouraging earthquake performance rating systems and disclosing them
to the public or developing such a rating system for city-owned buildings.
6. What incentive measures to encourage property owners undertake a structural retrofit should be
pursued?
The Advisory Group supported incentives for fee waivers, expedited permitting, and property-
assessed financing tools. There was minimal interest in deep financial assistance such as establishing
a special district or passing of bond measure to assist property owners financially. . Opinions were
split on the use of transfer of development rights, floor area ratio bonuses, and parking exemptions.
8. How much time do you feel is reasonable for property owners of at risk buildings in the community
to: a) prepare the initial structural evaluation reports for regulated buildings; and b), to complete
mandatory structural retrofits to their buildings?
2. POTENTIAL ISSUES FOR FUTURE STUDY AND CONSIDERATION
For some issues, based in part on Advisory Group discussions, additional information may be beneficial to help
develop a strategy and to better understand potential impacts on key stakeholders and community concerns.
Some of these issues are primarily economic and were outside the scope of the current study. The City Council
may wish to direct staff and/or outside consultants to investigate some of these items in more detail as the
seismic risk management program effort proceeds. These issues include the following:
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• Occupants and tenants
– How much would a typical retrofit add to the monthly rent of a multifamily soft-story wood
frame apartment tenant?
– Would some tenants be unable to afford a rent increase and seek housing elsewhere in Palo
Alto or move outside the city (and if so, how many might be displaced)?
– If soft-story wood frame apartments in Palo Alto are retrofitted in time before the next major
earthquake, how much less displacement of residents would occur as a result of the
earthquake?
– What categories of buildings are most important to address in order to help maintain the
commercial viability and vitality of the City’s core business districts and tax base?
• Property owners, developers, and business owners
– What are the characteristics of property owners that would be affected?
– How might small businesses be affected compared to larger ones?
– How many property owners are in need of lower cost capital or other substantial financial
assistance to fund retrofitting?
• Impacts of Seismic Restoration on Retention of Historic Structures in the City
– Insure that the review of initial seismic evaluations identify those structures that are listed in the
City’s Historic Inventory and flag them for attention during subsequent review.
– Develop a clear process for reviewing proposed seismic retrofits to historic structures that is
coordinated among responsible city departments and is consistent with current regulations and
Community policies.
– Seek out retrofit alternatives that are consistent with the Historic Building Code, historic
characteristics of the structure, and provide the most risk reduction.
• City departmental resources and budgets
– What would be the loss in revenue to the Building Department if fee waivers were offered?
– What would be the staffing and budgetary needs over time to administer an expanded program
that addresses additional building types?
– What kinds of interdepartmental cooperation and staff resources in other departments are
necessary to ensure effective implementation and coordination with other city planning and
public safety efforts?
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• Overall community economic health
– What kind of benefits could accrue to Palo Alto in terms of maintaining community function and
ability to recover if various building categories are retrofitted in time before the next major
earthquake?
• Other related issues
– It was brought up in the Advisory Group that the Building Department needs flexibility and
authority to take steps to get tough seismic mitigation projects done. One idea was to grant the
Building Official the ability to classify certain projects (with well-specified criteria) as warranting
a kind of “seismic safety” or “earthquake resilience” fast tracking, with city departments
agreeing to coordinate on a specified accelerated project review timeframe.
– Although outside the formal scope of this planning effort, several Advisory Group members
commented that it would be desirable for the City to do some kind of assessment of any
earthquake mitigation needs in public buildings and facilities serving the City.
– Advisory group members recommended the community be informed of Palo Alto’s overall
potential seismic risk by providing a summary of potential impacts on the City’s website,
including the expected performance of vulnerable buildings.
– The group also had a high degree of support for recommending that the City initiate and nest
future earthquake mitigation programs within a broader disaster or community resilience
initiative, as cities such as Los Angeles, Berkeley, and San Francisco have done. This could be
incorporated into the update of the City’s Comprehensive Plan Safety Element. There was
insufficient time in the project’s six advisory group meetings to consider potential initiatives to
assess risks for cell phone towers, water supply, facades, private schools, post-earthquake
shelter facilities, and/or other assets important to community recovery.
Attachment F