HomeMy WebLinkAboutStaff Report 9576
City of Palo Alto (ID # 9576)
City Council Staff Report
Report Type: Action Items Meeting Date: 3/18/2019
City of Palo Alto Page 1
Council Priority: Climate/Sustainability and Climate Action Plan
Summary Title: Proposed Draft Sea Level Rise Policy
Title: Acceptance of Proposed Policy to Plan for Sea Level Rise
From: City Manager
Lead Department: Public Works
RECOMMENDATION
Staff recommends that City Council:
1. Accept the attached Sea Level Rise Adaptation Policy (Attachment A), which will serve as a
guide for the development of a subsequent Sea Level Rise Adaptation Plan. This Plan will
serve as the Sustainability and Climate Action Plan–Sea Level Rise chapter;
2. Direct Staff to return to Council with a Sea Level Rise Adaptation Plan by December 2020.
EXECUTIVE SUMMARY
This report provides an overview of Palo Alto’s draft Sea Level Rise Adaptation Policy. The
purpose of the policy is to provide guidance in planning for rising tides that could impact Palo
Alto’s neighborhoods, economy, and the Baylands habitat. The Policy strives to ensure
consistency and integration with the City’s Comprehensive Plan (November 2017), the
Sustainability and Climate Action Plan (S/CAP) (November 2016) and related Sustainability
Implementation Plans (SIPs) (December 2017), the Local Hazard Mitigation and Adaptation Plan
(March 2017), the Baylands Master Plan (2008), Parks Master Plan (August 2017) and the Urban
Forest Master Plan (February 2019).
The Policy will serve as guidance in developing the more detailed Sea Level Rise Adaptation Plan
(Plan) to protect Palo Alto’s neighborhoods, economy, and Baylands hab itat. The Policy and
Plan are needed to complete the 2018-2020 SIPs which were accepted by Council in 2017 (Staff
Report 8487). The Plan will be delivered for Council review by December 2020 and will serve as
the Sea Level Rise Implementation Plan chapter of the 2020 S/CAP Update. The Plan will include
suggested measures to protect infrastructure, determine sea level height triggers for the Plan’s
various actions, and initiate adaptation strategies. The adaptation strategies of the Plan will
likely include measures such as revising building requirements, staff and public education, and
integrating sea level rise policy elements into other City operational procedures and plans.
City of Palo Alto Page 2
BACKGROUND
On May 31, 2016, staff presented a Study Session on Sea Level Rise to City Council (Staff Report
6953). At that study session, Staff identified facility-specific and programmatic issues that
involve sea level rise. Facilities that could be impacted by sea level rise include the Regional
Water Quality Control Plant, the Palo Alto Golf Course, the Palo Alto Airport, and the Municipal
Service Center. Services that could be impacted by sea level rise include critical underground
utilities, Highway 101, and emergency response capabilities. Six “Guiding Principles” and three
generic “Tools” (Protect, Adapt, and Retreat) were presented as a framework for Council
discussion on future sea level rise plans and projects, including the City of Palo Alto
Comprehensive Plan Update.
On November 28, 2016, Palo Alto City Council unanimously adopted the draft
Sustainability/Climate Action Plan (S/CAP) Framework (Staff Report 7304), which included goals
and strategies for sea level rise. The S/CAP Framework also included six Guiding Principles and
four goals for Sea Level Rise Response:
1. Plan for coming changes in our climate and environment
2. Protect the City from climate change induced hazards
3. Adapt to current and projected environmental conditions
4. Empower the local community and foster regional collaboration
DISCUSSION
Greenhouse gases trap the earth’s heat which warms land and oceans. This causes both
thermal expansion of the oceans and Antarctic and Greenland ice melt which together are the
primary sources of sea level rise globally and in San Francisco Bay.
Sea level rise threatens the operational integrity of critical services and facilities, e.g., Palo
Alto’s electrical, gas, water and wastewater utilities, the Municipal Service Center, the Palo Alto
Airport, Highway 101 and surrounding roads. Business districts and residential neighborhoods
within the projected sea level rise area are vulnerable to a rising Bay and potential future FEMA
insurance zone requirements.
Sea level rise is also likely to affect the elevation and salinity of groundwater close to the Bay.
Rising groundwater could have impacts on belowground infrastructure which may be subject to
corrosion and buoyancy effects and could contribute to liquefaction. In the case of very low-
lying areas, groundwater may result in surface flooding and long-term ponding.
Under the State of California’s Ocean Protection Council (OPC) 2018 Probabilistic Sea Level Rise
Projections, the Palo Alto Baylands may be submerged by mid-century which would eliminate
their ability to buffer upstream or Bayside flooding sources, attenuate storm surge, or
sequester carbon. The encroachment of Bay water may alter or eliminate habitat for
endangered species that reside in Palo Alto Baylands and the millions of birds that use the Palo
Alto segment of the Pacific Flyway for seasonal migration. The recreational and inspirational
City of Palo Alto Page 3
services of the Palo Alto shoreline could change if Baylands trails, playing fields, and golf course
are surrendered to encroachment of San Francisco Bay.
The decisions that Palo Alto makes in future years to adapt to rising tides extend beyond the
City’s borders. Implications with built features such as levees will impact adjacent communities
and thus require close coordination with surrounding local and regional agencies.
The proposed Sea Level Rise Adaptation Policy:
1. Recognizes that the best way to avoid long-term impacts from the worst sea level rise
predictions and to minimize adaption response costs is to reduce greenhouse gas (GHG)
contributions locally and to support regional, state, and national initiatives that reduce
GHGs.
2. Guides staff to lead by example and coordinate on sea level rise studies and planning
efforts with East Palo Alto, Mountain View, and other cities and public agencies,
including counties, as needed as well as utilities and public-private partnerships.
3. Standardizes the use of the Ocean Protection Council (OPC) 2018 Probabilistic Sea Level
Rise Projections for use in the City’s sea-level rise planning efforts for proposed
development projects, renovations and possible property acquisitions and other City
planning.
4. Provides a framework for the development of a Sea Level Rise Adaptation Plan which
would include a vulnerability assessment, short-term and long-term plan components,
and roles and responsibilities of staff.
The draft policy reflects extensive input from staff, subject matter experts working on sea level
rise and climate adaptation planning, and Palo Alto residents. Reviewers included:
Staff across City of Palo Alto Departments (Planning, Public Works, Utilities, Community
Services, Office of Emergency Services, City Manager’s Office, Open Space);
The San Francisco Estuary Institute–Resilient Landscapes Program. This program
develops innovative ecosystem restoration and management strategies to re-establish
and sustain key ecological functions and services. These strategies integrate natural and
human infrastructure to create systems that are more adaptive to climate change and
other stressors;
The Bay Area Climate Action Network (BayCAN). BayCAN is a collaborative network of
local government staff helping the Bay Area respond to the impacts of climate change
on human health, infrastructure and natural systems;
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UC Berkeley scientists and professors affiliated with the Climate Readiness Institute
(CRI). CRI utilizes experts from the region’s leading research institutions with expertise
in climate science, civil engineering, urban planning, ecology, oceanography, and law;
Staff from the cities of Mountain View, Santa Clara County, San Mateo County Sea
Change (oversees sea level rise planning efforts for the County); and,
Palo Alto residents who attended a public meeting on Wednesday February 27, 2019.
Invitees included members from the Parks and Recreation Commission and Baylands
Comprehensive Conservation Plan Committee, Save Palo Alto’s Groundwater and other
interested public members.
A separate Parks and Recreation Commission meeting is also scheduled for March 26, 2019
to assist in Sea Level Rise Adaptation Plan development.
Current Palo Alto Sea Level Rise Planning Efforts
The development of a sea level rise policy and a proposal for a Sea Level Rise Adaptation Plan
are two efforts among several to plan for sea level rise. Additional current City of Palo Alto sea
level rise-related planning efforts include:
1. A feasibility study for levee Improvements along the Palo Alto’s San Francisco Bay edge
via the Strategy to Advance Flood Control, Environmental Protection and Recreation
(SAFER) Project. This project will propose options for new and upgraded levee
alignments around Palo Alto Bay edge which also enhance habitat and recreation
opportunities. Palo Alto’s levees currently do not meet standards for Federal Emergency
Management Agency (FEMA) accreditation and may be vulnerable to overtopping from
future rising tides and storm surge. SAFER feasibility study and coordination with East
Palo Alto and Menlo Park is supported by the San Francisquito Creek Joint Powers
Authority. Staff will bring a feasibility study for proposed levee alignments to City
Council in 2019;
2. A conceptual design for a horizontal levee to be integrated into the SAFER alignment.
Horizontal levees are wide, engineered planted landscapes that mimic nature to
attenuate storm surge and rising tides, and sequester carbon. The preferred location
that was identified is at the east end of Embarcadero Road. A 30% design development
is in process;
3. The completion of a Baylands Vulnerability Assessment by the Community Services
Department in 2018. This document describes the potential impacts of sea level rise on
physical assets and habitats in the Baylands and high-level measures that the City can
take to adapt to climate change and sea level rise. This document can be used as a
starting point for planning efforts to address potential future impacts caused by sea
level rise and climate change.
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Public Works–Watershed Protection hopes to build upon this work to prioritize projects
that would protect critical infrastructure and to develop “Adaptation Pathways.”
“Pathways,” in relation to adaptation, is an approach designed to schedule adaptation
decision-making. It identifies the decisions that need to be taken now and those that
may be taken in future. The approach supports strategic, flexible and structured
decision-making. The pathways approach allows decision makers to plan for, prioritize,
and stagger investment in adaptation options. Sea level rise trigger points and
thresholds help them identify when to revisit decisions or actions. Examples of
pathways approaches can be translated into visual aids that help with stakeholder
communication. The adaptation pathway approach has been successfully applied in
adaptation planning for infrastructure and water management projects, and broader
cross-sector adaptation planning1;
4. Improved Stormwater Management. Stormwater runoff travels to low-lying areas in
Palo Alto which may also be impacted by sea level rise. Two recent stormwater
management efforts will reduce stormwater ponding contributions to projected sea
level rise inundation areas:
a) The Stormwater Management Fee. The Stormwater Management Fee ballot
measure passed in April 2017 with 64% of Palo Altans voting for the measure.
The Storm Water Management Program funds stormwater system maintenance
and provides for stormwater system improvements that prevent street flooding
and protect water quality. The program also provides litter reduction, creek
pollution prevention programs, commercial and residential rebates, and flooding
emergency- response services. Constructing Green Stormwater Infrastructure
projects is a new priority which includes infiltrating and cleansing storm water to
decrease peak flows to the conveyance system. ;
b) Green Stormwater Infrastructure (GSI) Framework. The GSI Framework was
adopted by Council in June 2017. Its purpose is to describe how the City will
gradually integrate GSI features into its urban landscape and stormwater
conveyance systems over several decades. GSI uses vegetation, soils, and natural
processes to manage stormwater runoff. It can help to avoid additional ponding
in areas that may also be flooded in future years by rising tides. GSI is partially
funded by the Stormwater Management Fee.
5. Sea level rise integration into City Planning Documents. Planning for Sea Level rise is
now referenced in the Local Hazard Mitigation and Adaptation Plan Revision and the
2030 Comprehensive Plan; and,
6. There are many Bay Area Regional efforts working to coordinate and provide resources
to public agencies for sea level rise planning. See Attachment B–Regional Sea Level Rise
Planning Efforts for a summary table.
1 CoastAdapt. (2019). Retrieved from https://coastadapt.com.au/pathways-approach
City of Palo Alto Page 6
Resource Impacts
Development of the Sea Level Rise Adaptation Policy to date required relatively small amounts
of staff time by each department and minimal consultant support. Should the Sea Level Rise
Policy be accepted by Council, resource requirements will increase to develop the follow-on Sea
Level Rise Adaptation Plan. Staff’s preliminary estimate is a one-time cost of $250,000 for
development of the Sea Level Rise Adaptation Plan, with ongoing costs for implementation of
the plan that will be evaluated during plan development. These budget needs, as well as a
position reclassification to provide coordination of the plan, are being considered through the
annual budget process. Once the City’s Policy and Plan are complete and the regional effo rts
are developed, the more difficult issues of locating funding for implementation will commence.
Policy Implications
The Sea Level Rise Adaptation Policy aligns with the 2019 Climate/Sustainability and Climate
Action Plan Council Priority.
Environmental Review
Acceptance by Council of and direction to staff regarding next steps concerning the Sea Level
Rise Adaptation Rise Policy is not a “project” approval under California Environmental Quality
Act (CEQA) because the action constitutes acceptance of a work program to develop a plan, and
the work program is subject to change, is non-binding and its acceptance would not result in a
direct or indirect physical change to the environment. If the action were considered a project, it
would be exempt from review under CEQA Guidelines Section 15061(b)(3) for the same
reasons. The plan that will be developed will be evaluated under CEQA prior to its consideration
by Council.
Attachments:
Attachment A - Sea Level Rise Policy
Attachment B - Summary of Regional Sea Level Rise Planning Efforts
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Sea Level Rise Adaptation Policy #-#/MGR
DRAFT Policy Version: March 1, 2019
SEA LEVEL RISE ADAPTATION
OVERVIEW
The State of California anticipates that relative sea level rise (SLR) projections stemming from greenhouse gas
emissions and related climate change pose significant economic, environmental and social risks to
communities along the San Francisco Bay Shoreline, including the City of Palo Alto. Research shows that these
projections may worsen if greenhouse gas emission trajectories continue unabated.1
Sea level rise in San Francisco Bay is anticipated to range between three feet to more than ten feet by 2100
with rising tides likely thereafter.2 In Palo Alto, many City services and infrastructure that are essential to the
City’s public health, safety and economy are located within areas that are predicted to be inundated by Bay
water if adaptation measures are not implemented.3
PURPOSE OF POLICY
The purpose of this policy is to plan for rising tides that could impact Palo Alto’s neighborhoods, economy and
the Baylands habitat, and to ensure consistency and integration with the range of City plans that call for SLR
planning such as the City’s 2030 Comprehensive Plan (adopted November 2017), the Sustainability and
Climate Action Plan (S/CAP) (November 2016) and related Sustainability Implementation Plans (SIPs), the Local
Hazard Mitigation and Adaptation Plan (March 2017), the Baylands Master Plan (2008), Baylands
Comprehensive Conservation Plan (in development), and the Urban Forest Master Plan (February 2019), and
other key planning documents that are produced. This policy will serve as a blueprint for the development of
a Sea Level Rise Adaptation Plan, and is not intended to establish requirements on new development for
implementation prior to Plan adoption; however, projects may be encouraged in advance to consider sea level
rise as part of the development process. Definitions and terminology relevant to this policy are listed in
Appendix 1– Policy Definitions and Related Terminology.
POLICY SUMMARY
The City recognizes that the best way to avoid long-term impacts from the worst SLR predictions and to
minimize adaption response costs is to reduce greenhouse gas (GHG) contributions locally and to support
regional, state and national initiatives that reduce GHGs.
Palo Alto will lead by example and coordinate on SLR studies and planning efforts with East Palo Alto,
Mountain View, and other cities and public agencies, including counties, as well as utilities, and public-private
partnerships, as needed. Palo Alto will establish interdepartmental SLR Planning responsibilities into City
1 Ocean Protection Council. (2018). State of California Sea-Level Rise Guidance 2018 Update. Retrieved from
http://www.opc.ca.gov/webmaster/ftp/pdf/agenda_items/20180314/Item3_Exhibit-A_OPC_SLR_Guidance-rd3.pdf. Page 12.
2 Reference 1, page 18.
3 San Francisco Bay Conservation and Development Commission Adapting to Rising Tides Program (2018). Adapting to Rising Tides
Bay Shoreline Flood Explorer online tool. Retrieved from https://explorer.adaptingtorisingtides.org/home.
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procedures and planning (see, e.g., Appendix 2–Departmental Responsibilities for Sea Level Rise Planning).
Palo Alto will use the Ocean Protection Council (OPC) 2018 Probabilistic SLR Projections published by the State
of California (Appendix 3) for proposed development projects, renovations and possible property acquisitions
and other City planning unless a more suitable reference is identified and agreed upon by local agencies
tasked with SLR preparedness. City of Palo Alto, business and residential investments in new property,
development, and infrastructure should be designed based on OPC SLR projections for the useful life of the
asset to avoid flooding or erosion. To that end, the forthcoming Sea Level Rise Adaptation Plan should
consider the following best practices:
1. Upgrades to existing property or infrastructure that are considered less-critical (not essential to
immediate public health and safety, e.g. trails or playing fields) should consider the impacts of SLR
beyond 2050 using the Low Risk Aversion or Medium-high Risk Aversion Projection listed in Table 1;
2. For critical development and infrastructure (e.g., wastewater treatment facility or utilities that are
essential to public health and safety), a risk assessment should be completed based on the SLR
projections to 2100 and to include the lifetime of the building using the Medium-high or Extreme Risk
Aversion Projections;
3. All designs and engineering strategies, where possible and financially feasible, should be adaptable to
changing climate predictions. Each new development should be required to develop and maintain an
individual “adaptation pathway plan” to prepare for changes in rising sea level, and related
groundwater intrusion. In all sea level rise assessments, and where data are available, the City will
consider Base Flood Elevations, storm surge, groundwater table changes due to rising sea levels, and
wave runup, where appropriate.
BACKGROUND
Greenhouse gases trap the earth’s heat which warms land and oceans. This causes both thermal expansion of
the oceans and Antarctic and Greenland ice melt which together are the primary sources of SLR globally and in
San Francisco Bay.
SLR threatens the operational integrity of critical services and facilities, e.g., Palo Alto’s electrical, gas, water
and wastewater utilities, the Municipal Service Center, the Palo Alto Airport, Highway 101 and surrounding
roads. Business districts and residential neighborhoods within the projected SLR area are vulnerable to a rising
Bay and potential future FEMA insurance zone requirements.
SLR is also likely to affect the elevation and salinity of groundwater close to the Bay. Rising groundwater could
have impacts on belowground infrastructure which may be subject to corrosion and buoyancy effects and
could contribute to liquefaction. In the case of very low-lying areas, groundwater may result in surface
flooding and long-term ponding.
Under current SLR predictions, the Palo Alto Baylands may be submerged by mid-century which would
eliminate their ability to buffer upstream or Bayside flooding sources, attenuate storm surge or sequester
carbon. The encroachment of Bay water may alter or eliminate habitat for endangered species that reside in
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Palo Alto Baylands and the millions of birds that use the Palo Alto segment of the Pacific Flyway for seasonal
migration. The recreational and inspirational services of the Palo Alto shoreline could change if Baylands trails,
playing fields and golf course are surrendered to encroachment of San Francisco Bay.
The decisions that Palo Alto makes in future years to adapt to rising tides extend beyond the City’s borders.
Implications with built features such as levees will impact (help or imperil) adjacent communities and thus
require close coordination with surrounding local and regional agencies.
PROCEDURES FOR POLICY IMPLEMENTATION
1. The City will:
a) conduct a SLR vulnerability assessment, which will:
i. identify critical and less-critical City infrastructure and ecosystem assets to manage risks
given predicted SLR scenarios through 2100 and beyond;
ii. Identify hazards and determine tolerable risks of the City and community members (risk =
hazard x exposure x vulnerability; risk ($/year) = frequency (events/year) x consequences
($/event);
iii. include an economic assessment of SLR vulnerability for public and private property and
cost estimates for inaction;
iv. engage community members in the process.
b) develop a multi-year SLR Implementation Plan to coordinate internal and regional SLR
planning, project funding and public outreach. The Plan will include a SLR adaptation plan and
timeline which will:
i. align with the intent and language of the City’s various plans, policies and documents that
intersect with SLR Policy and Plan (e.g., the Comprehensive Plan, Sustainability and Climate
Action Plan, Local Hazard Mitigation Plan, Baylands Comprehensive Conservation Plan,
Baylands Master Plan, Regional Water Quality Control Plant Long Range Facility Plan,
Urban Water Management Plan, Recycled Water Strategic Plan, Parks Master Plan, etc.);
ii. include a table of prioritized adaptation pathways to manage risks to natural and built
assets based on the SLR Vulnerability Assessment. Adaptation pathways provide a menu of
recommendations and logically staged phases for adaptation over time based on triggers
related to SLR levels. Adaptation pathways factor in cost/benefits, the lengthy time to plan,
fund and build response strategies and potential additional benefits of carbon
sequestration, GHG reduction, wildlife protection and social equity;
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iii. include a development plan for public and private property anticipated to be impacted by
SLR which may include:
a. changing the city zoning map and amending requirements, restrictions, or municipal
codes to be stricter than state or federal requirements as necessary and when
feasible to reduce risks;
b. adding conditions of approval for project permits in areas where there is a SLR or
groundwater intrusion risk;
c. establishing geographic areas and/or triggers for requiring consideration of
relocation;
d. developing restrictions or additional criteria; and
e. funding identification
f. educate and engage community members in the process of SLR planning, including
creating a SLR Task Force and meeting with stakeholders (e.g., realtors, property
owners, etc.) to educate them about SLR and the options, tradeoffs, and costs, for
resilience;
iv. address budget and funding considerations for additional or existing staff to perform SLR
planning, adaptation and Capital Improvement Projects (CIPs);
v. provide guidance on managing and enhancing Baylands, creek and open space ecosystem
services to mitigate SLR impacts through carbon sequestration and absorption. Examples of
this include the use of horizontal levees, expanding or improving Baylands habitat; this
guidance should consider the use of the Baylands Comprehensive Conservation Plan, and
the concept of “Operational Landscape Units” developed by San Francisco Estuary Institute
which delineate Bay shoreline ecosystem functions and services within the natural and
built environment and not by jurisdictional boundaries, and;
vi. include the development of educational materials and technical assistance for staff and
developers, including:
a. a checklist and primer on SLR, risk and sharing risk, and planning guidance;
b. technical and regulatory guidance to City engineers and public developers so that
projects are designed based on accepted OPC SLR assumptions and which prompt
design-standard revisions, and protect, adapt, retreat responses for threatened
areas;
c. a risk assessment process to be used during CIP site selection, planning and property
purchases;
d. a SLR and groundwater projection zone map which also shows the intersection of
the FEMA flood zone and associated insurance requirements;
2. Recognize policy limits: This policy does not establish specific requirements for all projects because
each site condition is unique, but instead provides expectations for developing guidance and tools to
answer key building and infrastructure design and SLR response strategies . This policy also recognizes
that not all codes and regulations that govern construction are yet synchronized with OPC SLR
predictions, however Palo Alto will incorporate SLR guidance and planning into its own construction
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and planning process proactively for both public and private structures until regional standards are
adopted for use.
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Appendix 1: Policy Definitions and Related Terminology
Adaptation Pathway: “Pathways” in relation to adaptation is an approach designed to schedule
adaptation decision-making. It identifies the decisions that need to be taken now and those that may be
taken in future. The approach supports strategic, flexible and structured decision-making. The pathways
approach allows decision makers to plan for, prioritize and stagger investment in adaptation options.
Trigger points and thresholds help them identify when to revisit decisions or actions. Examples of
pathways approaches can be translated into visual aids such as “route maps” that support communication
and consultation with stakeholders. The adaptation pathway approach has been successfully applied in
adaptation planning for infrastructure and water management projects, and broader cross-sector
adaptation planning4.
Baylands: Lands which are located between the lines of mean high tide and mean low tide (California
Coastal Commission Sea Level Rise Policy Guidance).
Base Flood Elevation (1% annual chance flood): A flood that has a 1% probability of occurring in any given
year. The 100-year floodplain is the extent of the area of a flood that has a 1% chance of occurring or being
exceeded in any given year. This is indicated by the Special Flood Hazard Area (SFHA) on FEMA flood maps.
Baylands Comprehensive Conservation Plan: A plan currently being prepared by the City of Palo Alto that
provides specific programs and projects to achieve the goals and policies of the Baylands Master Plan.
Baylands Master Plan: A plan prepared by the City of Palo Alto to provide a framework and guide for
actions in the Baylands that seek to preserve the area’s unique natural, recreational and flood -prevention
resources.
Capital Improvement Program (CIP): The Capital Improvement Program (CIP) includes projects that help
maintain or improve City assets, often called infrastructure. To be included in the City of Palo Alto Capital
Budget, a project must meet the following criteria:
Must have a minimum cost of $50,000 for each stand-alone unit or combined project.
Must have a useful life of at least five to seven years (the purchase or project will still be
functioning and not be obsolete at least five to seven years after implementation).
Must extend the life of an existing asset or provide a new functional use for an existing asset for
at least five years. Examples include extensive roof rehabilitations. These improvements are
distinguished from ongoing maintenance work that may extend the life of the asset but is done
on a routine basis.
Climate change: Any long-term change in climate conditions in a place or region, whether due to natural
causes or as a result of human activity.
Comprehensive Plan: The City of Palo Alto Comprehensive Plan (or Comp Plan) is the primary tool for
guiding land use and development in Palo Alto. The Plan fulfills the State requirement that the City adopt
4 CoastAdapt. (2019). Retrieved from https://coastadapt.com.au/pathways-approach
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a General Plan. The Plan provides a foundation for the City’s development regulations, capital
improvements program, and day-to-day decisions.
Critical infrastructure: City built assets with a long-projected life span (greater than 50 years) which if
compromised by rising tides could potentially have catastrophic results on public health, safety or well-
being, e.g., wastewater treatment facilities, stormwater infrastructure, levees or impoundments, bridges
along major evacuation routes, airports, seaports, railroads, and major highways,
EOC/Fire/Police/Healthcare, schools, homeless shelters, landfills and contaminated sites.
Less-critical Infrastructure: City assets that have an expected lifetime of 10-20 years or is replaceable and
adaptable, or has limited interdependencies and limited consequences should the system fail or be
inundated by water. Examples include isolated parks, unpaved trails.
Design life: The life expectancy of a project as determined during design. As opposed to useful life (see
below).
Erosion: The wearing away of land by natural forces; on a beach, the carrying away of beach material by
wave action, currents, or the wind , the loss of marsh due to the erosion of the marsh edge by waves.
Development and other non-natural forces (e.g., water leaking from pipes or scour caused by wave action
against a seawall) may create or worse erosion problems (California Coastal Commission Sea Level Rise
Policy Guidance).
Facilities: All buildings, communications facilities, energy systems, industrial facilities, all transportation
networks, water and wastewater systems, and parks.
Flood (or Flooding): Refers to normally dry land becoming temporarily covered in water, either
periodically (e.g., tidal flooding, king tides) or episodically (e.g., storm surge or tsunami flooding).
Greenhouse gases (GHGs): Any gas that absorbs infrared radiation in the atmosphere. Greenhouse gases
include, carbon dioxide, methane, nitrous oxide, ozone, chlorofluorocarbons, hydrochlorofluorocarbons,
hydrofluorocarbons, perfluorocarbons, sulfur hexafluoride.
Green Stormwater Infrastructure (GSI): Infrastructure that uses vegetation, soils, and natural processes to
manage stormwater runoff and reduce peak flows in flood control channels or creeks. Examples of GSI
include landscape-based stormwater “biotreatment” using soil and plants ranging in siz e from grasses to
trees; pervious paving systems (e.g., interlocking concrete pavers, porous asphalt, and pervious concrete);
rainwater harvesting systems (e.g., cisterns and rain barrels); and other methods to capture and use
stormwater as a resource.
Groundwater: The water found below the surface of the land and contained in the pore spaces of
saturated geologic media (sand, gravel). Groundwater is either rain water that has seeped through the soil
surface and by means of gravity of soil conditions drained from high to lower elevation areas.
Groundwater can also come from the bay transferred via bay mud under the existing levees. Groundwater
can be source of water found in wells and springs.
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Hazard: A situation involving danger such as coastal flooding, earthquake rainfall and local flooding.
Local Hazard Mitigation Plan: The Federal Disaster Mitigation Act of 2000 (DMA) requires all cities,
counties, and special districts to adopt a Local Hazard Mitigation Plan (LHMP) to receive disaster mitigation
funding from the Federal Emergency Management Agency (FEMA). Hazard mitigation planning is the
process used by state, local and tribal leaders to understand risks from natural hazards and develop long-
term strategies to reduce the impacts of disasters on people, property, and the environment. The Palo Alto
Local Hazard Mitigation Plan is updated every three years.
Mean Sea Level: The average relative sea level over a period, such as a month or a year, long enough to
average out transients such as waves and tides.
Ocean Protection Council (OPC): The Council was created pursuant to the California Ocean Protection
Act (COPA), which was signed into law in 2004 by Governor Arnold Schwarzenegger. The mission of the
OPC is to “…ensure that California maintains healthy, resilient, and productive ocean and coastal
ecosystems for the benefit of current and future generations. The OPC is committed to basing its decisions
and actions on the best available science, and to promoting the use of science among all entities involved
in the management of ocean resources.” The OPC published the State of California Sea Level Rise Guidance
Document and subsequent updates which provides an estimated range of predicted SLR and subsequent
updates.
Operational Landscape Units: A delineated area that effectively provides specific ecosystem functions and
services within the natural and built environment.
Pacific Flyway: A major north-south flyway for migratory birds in America, extending from Alaska to
Patagonia. Every year, migratory birds travel some or all of this distance both in spring and in fall, following
food sources, heading to breeding grounds, or travelling to overwintering sites.
Protect, adapt, retreat strategies: Responding to SLR generally involves three general concepts:
Protect: Implementing strategies that reduce the risk of SLR impacts to land e.g., levees, horizontal
levies, floodwalls, flood gates, and wetlands;
Adapt: Adjusting to natural or human systems in response to actual or expected climatic stimuli or
their effects, which minimizes harm or takes advantage of beneficial opportunities. This includes
building any new or substantially-improved structures elevated above future flood levels or as
structures that can be submerged without sustaining appreciable damage.
Retreat: Surrendering an area partially, seasonally or completely to rising sea level;
Regional Water Quality Control Plant (RWQCP): Owned and operated by the Palo Alto, the Plant treats
wastewater for the communities of Los Altos, Los Altos Hills, Mountain View, Palo Alto, Stanford University
and the East Palo Alto Sanitary District. The mission of the RWQCP is to protect San Francisco Bay by
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cleaning and treating wastewater before it is discharged.
Relative Sea Level: Sea level measured by a tide gauge with respect to the land upon which it is situated.
Risk: Often expressed as “hazard x exposure x vulnerability;” in terms of costs per year it can be expressed
as “frequency (events/year) x consequences ($/event).
SAFER Bay Project Feasibility Report: SAFER (Strategy to Advance Flood protection, Ecosystem and
Recreation along San Francisco Bay) has prepared a feasibility report that is in the review and comment
phase. Once City staff comments are made and report revised as needed, the report will be available for
public review and comment.
Sea level: The height of the ocean relative to land; tides, wind, atmospheric pressure changes, heating,
cooling, and other factors cause sea level changes.
Sea level rise (SLR): Sea level can change, both globally and locally, due to (a) changes in the shape of the
ocean basins, (b) changes in the total mass of water and (c) changes in water density. Factors leading to
SLR under climate change include both increases in the total mass of water from melting land-based snow
and ice, and changes in water density from an increase in ocean water temperatures and salinity changes.
Relative SLR occurs where there is a local increase in the level of the ocean relative to the land, which
might be due to ocean rise and/or land level subsidence.
Storm Surge: A rise above normal water level due to low atmospheric pressure associated with storms and
the action of wind stress on the water surface.
Sustainability and Climate Action Plan (S/CAP): Palo Alto’s plan to reduce the city and community’s
greenhouse gas emissions to meet climate protection goals and also consider broader issues of
sustainability, such as sea level rise, land use and biological resources.
Sustainability Implementation Plans (SIPS): Specific actions needed to achieve S/CAP goals.
Useful life: The period over which a project is expected to be available for use by an entity. This period of
time typically exceeds the design life (see above).
Threat and Hazard Identification and Risk Assessment (THIRA): A THIRA helps communities better
understand the hazards from natural, technological, and human-caused threats that pose the greatest risk.
The Palo Alto THIRA report is updated every two years.
Vulnerability: The extent to which a species, habitat, ecosystem, or human system is susceptible to harm
from climate change impacts. More specifically, the degree to which a system is exposed to, susceptible to,
and unable to cope with, the adverse effects of climate change, including climate variability and extremes.
Vulnerability is a function of the character, magnitude, and rate of climate variation to which a system is
exposed, as well as of non-climatic characteristics of the system, including its sensitivity, and its coping and
adaptive capacity.
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Vulnerability Assessment: A practice that identifies who and what is exposed and sensitive to change and
how able a given system is to cope with extremes and change. It considers the factors that expose and
make people or the environment susceptible to harm and access to natural and financial resources
available to cope and adapt, including the ability to self-protect, external coping mechanisms, support
networks, and so on.
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Appendix 2–Departmental Responsibilities for Sea Level Rise Planning
The following table is a menu of potential actions to be confirmed in the plan for each
department.
Lead Department Responsibility
Administrative Services
Department
1. Revise Purchasing Department construction solicitation
templates and contract documents to include SLR and
sustainability considerations.
2. Prioritize SLR planning and budget equal to other performance
indicators for projects within projected SLR areas.
City Manager’s Office 1. Implement the Sustainability and Climate Action Plan to
reduce greenhouse gas emission contributions.
2. Include SLR update with annual Earth Day and Sustainability
Implementation Plan reporting.
3. Consider development of key performance indicators to track
if the City is meeting its SLR planning goals.
4. Provide outreach through City Manager Office communication
channels about how the City is preparing for sea level rise in
coordination with Public Works and Utilities Department
outreach.
5. Prioritize SLR projects equal to other Council priorities.
Community
Services/Open Space
Implement the recommendations of the 2019 Palo Alto Baylands
Vulnerability Assessment for flood control, access, non-recreational
features and facilities, habitats and wildlife where feasible, e.g.:
1. Seek funding to expand and enhance Baylands habitat to
leverage wave attenuation, water absorption and other
ecosystem services that mitigate SLR.
2. Develop climate-smart planting palettes that are projected to
survive under changing climate conditions.
Office of Emergency
Services
Continue to consider sea level rise in community risk assessments,
such as Threat and Hazard Identification Risk Assessment and Local
Hazard Mitigation Plan, with appropriate risk considerations and
weighting.
Planning & Community
Environment
1. Update zoning code and related requirements, such as design
standards for public and private development based on OPC
predictions.
Public Works–Airport 1. Plan for SLR to reduce risk of impacts to Airport operations.
2. Seek funding opportunities with the Federal Aviation
Administration and Caltrans Division of Aeronautics.
Public Works–
Interdepartmental
1. Coordinate groundwater management in recognition that SLR
will push groundwater levels inland and closer to the surface.
2. Explore the interaction between groundwater, Sea Level Rise
and Stormwater.
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Public Works–
Engineering
1. Plan, design, identify funding, build and maintain resiliency
features in City planning and CIP projects per the City’s
Comprehensive Plan, e.g.:
a) Manage the preparation of SAFER feasibility report and
potential environmental review, funding, public
outreach and construction of SAFER levees and related
projects to mitigate SLR.
b) Seek grants and other funding for design alternatives
and structures that mitigate SLR.
c) Build design alternatives and structures that mitigate
SLR.
2. Manage the implementation of large-scale stormwater
infrastructure rehabilitation projects to minimize flooding from
upstream sources, e.g.:
a) Construct the high priority projects identified through
Storm Drain Master Plan and listed with the
Stormwater Management Fee and consider integration
of GSI Plan elements.
b) Address FEMA regulations (flooding risks) and sea level
rise associated with at least 100-year storm events for
at least the design life of the structure.
c) Manage stormwater rebate program and coordinate
with development services, inspect project sites once
completed and issue rebates to property owners for
installed rainwater capture devices.
d) Work with Development Services to help developers of
private projects comply with SLR policy and plans and
FEMA regulations.
e) Implement County Hazard Mitigation Plan (FEMA).
f) Implement Green Stormwater Infrastructure Plan
requirements.
g) Design new infrastructure to be flexible so that it may
be incrementally enhanced as sea level rise increases
Public Works–
Environmental Services
1. Coordinate internal discussions on SLR planning at a frequency
that facilitates proactive planning, e.g., quarterly or as needed.
2. Manage SLR risks to allow for ongoing operations of the
RWQCP and the sanitary landfill;
3. Seek opportunities and funding to enhance the Baylands
ecosystem and build and nature-based features such as
horizontal levees.
4. Maintain AB2516 Ocean Protection Council semi-annual
report.
5. Conduct Public Outreach on SLR education and planning in
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coordination with the City Manager’s Office and Utilities.
6. Prepare Policy updates.
7. Lead Green Stormwater Infrastructure planning and
implementation.
Utilities 1. Execute energy portfolio-related actions in the SIPs Plan for
Utilities-related asset protection from flooding, SLR and
erosion.
2. Increase climate and SLR messages in ongoing water
conservation public awareness campaigns in coordination with
the City Manager’s Office and Public Works–Watershed
Protection.
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Appendix 3–Ocean Protection Council 2018 Probabilistic Sea Level Rise Projections
Rising Seas Report, State of California Sea Level Rise Guidance*
Low Risk Aversion
Likely Range (ft.)
66% Probability
Medium-high Risk
Aversion (ft.)
0.5% probability
1-in-200 chance
Extreme Risk
Aversion (ft.)
(No probability yet
available)**
Use for less-critical infrastructure and services
e.g., trails, playing fields, golf course that could
potentially be surrendered to SLR.
Use for critical infrastructure and services
e.g., Regional Water Quality Control Plant,
Municipal Service Center, Utilities infrastructure
2030 0.5 0.8 1.0
2040 0.8 1.3 1.8
2050 1.1 1.9 2.7
2060 1.5 2.6 3.9
2070 1.9 3.5 5.2
2080 2.4 4.5 6.6
2090 2.9 5.6 8.3
2100 3.4 6.9 10.2
SLR rates in this table show the upper-range predictions for how SLR may increase in future years and the
SLR rate assumptions that should be used for different facilities and development. Probabilistic projections
in the first two columns are with respect to a baseline of the year 2000, or more specifically the average
relative sea level over 1991 - 2009. These numbers do not include impacts of El Niño, storms or other
acute additions to sea-level rise.5 The time period referenced should be based on the useful life of the
structure. The low and medium-risk projections listed in this table may underestimate the likelihood of
extreme sea-level rise, particularly under high greenhouse gas emissions scenarios which as the writing of
this policy are projected to continue to increase.
Not all infrastructure and development need to be designed to withstand the most extreme SLR
predictions. This table suggests the types of facilities that could be designed to withstand the low, medium
or extreme risk scenarios. Buildings for which there is an extreme risk aversion (e.g. wastewater treatment
facilities) require more extensive and thus more costly designs and retrofits.
*The relative SLR heights above as it relates to Palo Alto’s shoreline can be viewed at Adapting to Rising
Tides Bay Shoreline Flood Explorer online tool at https://explorer.adaptingtorisingtides.org/home.
** OPC guidance also includes an Extreme Risk Aversion scenario (aka H++ Scenario (Sweet et al 2017
Single scenario)). The probability of this scenario is currently unknown, but its consideration is important,
particularly for high stakes, long-term decisions for critical infrastructure and given the uncertainties of
projected GHG emissions discussed above.
5 Ocean Protection Council. (2018). State of California Sea-Level Rise Guidance 2018 Update. Retrieved from
http://www.opc.ca.gov/webmaster/ftp/pdf/agenda_items/20180314/Item3_Exhibit-A_OPC_SLR_Guidance-rd3.pdf. Page 18.
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Attachment B–Summary of Regional Sea Level Rise Planning Efforts
Organization Name Organization Description
Adapting to Rising Tides (ART) ART is a collaborative planning effort led by San
Francisco Bay Conservation and Development
Commission (BCDC) and the National Oceanic and
Atmospheric Administration (NOAA) Coastal Services
Center to understand how San Francisco Bay Area
communities can adapt to sea level rise and storm
event flooding. The ART Project has engaged local,
regional, state and federal agencies, as well as non-
profit and private stakeholders, to explore how the Bay
Area can increase resilience to sea level rise and storm
events, while protecting critical ecosystem and
community services.
Bay Area Climate Adaptation Network
(BayCAN)
BayCAN is a collaborative network of local government
staff helping the Bay Area respond effectively and
equitably to the impacts of climate change on human
health, infrastructure and natural systems.
Resilient By Design A year-long collaborative design challenge bringing
together local residents, public officials and local,
national and international experts to develop
innovative community-based solutions that will
strengthen our region’s resilience to sea level rise,
severe storms, flooding and earthquakes.
San Francisco Bay Conservation and
Development Commission (BCDC)
The BCDC is a 27-member commission authorized to
control bay filling and dredging, and bay-related
shoreline development.
San Francisco Bay Regional CHARG - Coastal
Hazards Adaptation Resiliency Group (CHARG)
CHARG is a forum at which local, regional, state, and
federal scientists, engineers, planners, and policy
makers can develop a common understanding about
regional coastal hazards issues. CHARG’s participants
represent many Bay Area cities (including Palo Alto), all
nine Bay Area counties, and regional, state, and federal
agencies. CHARG shifted its focus in 2017 to supporting
technical studies and solutions to inform regional
adaption, policy, and funding decisions. In 2018, CHARG
became a Strategic Initiative of the Bay Area Flood
Protection Agencies Association (BAFPAA). CHARG
seeks to engage all local flood control districts and
stakeholders from San Francisco Bay through the
Sacramento-San Joaquin Delta to advance the scientific
foundation needed to direct sea level rise adaptation at
2
a regional scale.
San Francisquito Creek JPA (SFCJPA) The SFCJPA is a regional government agency founded
by the cities of East Palo Alto, Menlo Park, and Palo
Alto, the San Mateo County Flood Control District and
Santa Clara Valley Water District in 1999 following a
major flood the preceding year. The SFCJPA plans,
designs and implements capital projects which are
comprehensive in terms of geography and function
because they cross jurisdictional boundaries and serve
to reduce a proven flood threat, enhance ecosystems
and recreational opportunities, and connect our
communities.
San Mateo County Sea Change Sea Change SMC addresses the challenge of sea level
rise by working together with and providing resources
to local governments, stakeholder agencies and
communities groups to create a prepared and stronger
County.
South Bay Shoreline Study The South San Francisco Bay Shoreline Project is a
Congressionally authorized study by the US Army Corps
of Engineers together with the Santa Clara Valley Water
District and the State Coastal Conservancy to identify
and recommend flood risk management projects for
Federal funding. The Corps is looking at projects that
will reduce flood risk, restore some of the region's lost
wetlands, and provide related benefits such as
recreation and public access.
Strategy to Advance Flood protection,
Ecosystems, and Recreation (SAFER)
The SFCJPA’s SAFER Bay project will evaluate
infrastructure alternatives to protect Menlo Park, East
Palo Alto, and Palo Alto against extreme tides with sea
level rise and enhance shoreline habitat and trails.