HomeMy WebLinkAbout2004-05-03 Ordinance 4824follows:
ORDINANCE NO. 4824
ORDINANCE OF THE COUNCIL OF THE CITY OF PALO
ALTO AMENDING PALO ALTO MUNICIPAL CODE SECTIONS
16.52.040 AND 16.52.130 OF CHAPTER 16.52
PERTAINING TO FLOOD HAZARD REGULATIONS
The Council of the City of Palo Alto does ORDAIN as
SECTION 1. Section 16.52.040 (Definitions) of Chapter
16.45 (Flood Hazard Regulations), Title 16 [Building
Regulations] of the Palo Alto Municipal Code is hereby amended
to read as follows:
16.52.040 Definitions.
(a) The definitions contained hereafter shall govern
the interpretation of the terms defined for the purposes of this
chapter, except where the context clearly requires otherwise.
Words used in this chapter and not defined in this section shall
be interpreted so as to gi ve them the meaning they have in
common usage and to give this chapter its most reasonable
application.
(1) "Appeal" means a request for a review of the
floodplain administrator I s interpretation of any provision of
this chapter or a request for a variance.
(2) "Area of shallow flooding" means a designated AO
or AH zone on the Flood Insurance Rate Map. The base flood
depths range from one to three feet; a clearly defined channel
does not exist; the path of flooding is unpredictable and
indeterminate; and velocity flow may be evident.
(3) "Area of Special Flood Hazard." See "Special flood
hazard area."
(4) "Base flood" or "one hundred year flood" means the
flood having a one percent chance of being equaled or exceeded
in any given year.
(5) "Basement" means any area of the building having
its floor subgrade (below ground level) on all sides.
(6) "Breakaway walls" means any type of walls, whether
solid or lattice, and whether constructed of concrete, masonry,
wood, metal, plastic or any other sui table building material
which is not part of the structural support of the building and
which is designed to break away under abnormally high tides or
wave action without causing any damage to the structural
integrity of the building on which they are used or any
buildings to which they might be carried by floodwaters. A
breakaway wall shall have a safe design loading resistance of
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not less than ten and no more than twenty pounds per square
foot. Use of breakaway walls must be certified by a registered
engineer or architect and shall meet the following conditions:
(A) Breakaway wall collapse shall result from a water
load less than that which would occur during the base flood; and
(B) The elevated portion of the building shall not
incur any structural damage due to the effects of wind and water
loads acting simultaneously in the event of the base flood.
(7) "Coastal high hazard area" is the area subject to
high velocity waters, including coastal and tidal and inundation
or tsunamis. The area is designated on the Flood Insurance Rate
Map as Zone Vl -V30, VE or V.
(8) II Development" means
improved or unimproved real estate,
buildings or other structures,
grading, paving, excavation or
storage of equipment or materials.
any man-made change to
including but not limited to
mining, dredging, filling,
drilling operations or bulk
(9) "Flood" or "Flooding" means a general and
temporary condition of partial or complete inundation of
normally dry land areas from (A) the overflow of floodwaters,
(B) the unusual and rapid accumulation or runoff of surface
waters from any source, and/or (C) the collapse or subsidence of
land along the shore of a lake or other body of water as a
result of erosion or undermining caused by waves or currents of
water exceeding anticipated cyclical levels or suddenly caused
by an unusually high water level in a natural body of water,
accompanied by a severe storm, or by an unanticipated force of
nature, such as flash flood or an abnormal tidal surge, or by
some similarly unusual and unforeseeable event which results in
flooding.
(lO) "Flood Boundary and Floodway Map" means the
official map on which the Federal Emergency Management Agency or
Federal Insurance Administration has delineated both the areas
of flood hazard and the floodway.
(ll) "Flood Insurance Rate Map" means the official map
on which the Federal Emergency Management Agency or Federal
Insurance Administration has delineated both the areas of
special flood hazard and the risk premium zones applicable to
the conununity.
(l2) "Flood Insurance Study" means the official report
provided by the Federal Insurance Administration that includes
flood profiles, the Flood Insurance Rate Map, the Flood Boundary
and Floodway Map, and the water surface elevation of the base
flood.
(13) "Floodplain or flood-prone area" means any land
area susceptible to being inundated by water from any flood.
(l4) "Floodplain management" means the operation of an
overall program of corrective and preventive measures for
reducing flood damage, including but not limited to emergency
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preparedness plans, flood control works and floodplain
management regulations.
(15) "Floodplain management regulations" means zoning
ordinances, subdivision regulations, building codes, health
regulations, special purpose ordinances (such as floodplain
ordinance, grading ordinance and erosion control ordinance) and
other applications of police power. The term describes such
State of California or local regulations in any combination
thereof, which provide standards for the purpose of flood damage
prevention and reduction.
(16) "Floodproofing" means any combination of
structural and nonstructural additions, changes or adjustments
to non-residential structures which reduce or eliminate flood
damage to real estate or improved real property, water and
sanitary facilities, structures and their contents.
(17) "Floodway" or "regulatory floodway" means the
channel of a river or other watercourse and the adjacent land
areas that must be reserved in order to discharge the base flood
without cumulatively increasing the water surface elevation more
than one foot.
(18) "Functionally dependent use" means a use which
has an intended purpose that cannot be performed, unless it is
located or carried out in close proximity to water. The term
includes only docking facilities, port facilities that are
necessary for the loading and unloading of cargo or passengers,
and shipbuilding and ship repair facilities, but does not
include long-term storage or related manufacturing facilities.
(19) "Highest adjacent grade" means the highest
natural elevation of the ground surface prior to construction
next to the proposed walls of a structure.
(20) "Historic structure" means any structure that is
listed individually in the National Register of Historic Places
or in the State of California Register of Historical Resources
or any structure that is listed individually in the current
edition of the Palo Alto Master List of Structures on the
Historic Inventory in Category 1 "Exceptional BuildingH or
Category 2 "Major BuildingH or any structure that has been
certified by the Keeper of the National Register as contributing
to the historical significance of a registered historic
district.
(21) "Lowest floor" means the lowest floor of the
lowest enclosed area, including basement.
(A) An unfinished or flood resistant enclosure below the
lowest floor that is usable solely for the parking of vehicles,
building access or storage in an area other than a basement area
is not considered a building's lowest floor, provided that it
conforms to the applicable non-elevation design requirements,
including but not limited to:
(1) The standard set forth in subdivision (3) of
subsection (c) of Section 16.52.130i
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(2) The anchoring standards set forth in subdivision
(1) of subsection (a) of Section 16.52.130;
(3) The construction materials and methods standards
set forth in subsection (b) of Section 16.52.130; and
(4) The standards for utili ties set forth in Section
16.52.140.
(B) For residential structures, all subgrade enclosed
areas are prohibi ted as they are considered to be basements.
This prohibition includes below-grade garages, storage areas and
subfloor crawl spaces, except existing below-grade subfloor
crawl spaces meeting the standards set forth in subsection (d)
of Section 16.52.130.
(22) "Manufactured home" means a structure,
transportable in one or more sections, which is built on a
permanent chassis and is designed for use with or without a
permanent foundation when it is attached to the required
utilities. The term does not include a recreational vehicle.
(23) "Manufactured home park or subdivision" means a
parcel (or contiguous parcels) of land divided into two or more
manufactured home lots for sale or rent.
(24) "Market Value of the structure" means that value
of a structure determined by estimating the cost to replace the
structure in a new condition and adjusting that cost figure by
the amount of depreciation which has accrued since the structure
was constructed. The cost of replacement of the structure shall
be based on a square foot cost factor determined by reference to
a building cost estimating guide recognized by the building
construction industry, as approved by the floodplain
administrator. The amount of depreciation shall be determined
by taking into account the age and physical deterioration of the
structure and functional obsolescence, as approved by the
floodplain administrator, but shall not include economic or
other forms of external obsolescence. The use of replacement
costs or accrued depreciation factors different from those
contained in recognized building cost estimating guides may be
approved at the discretion of the floodplain administrator only
if such factors are included in a report prepared by an
independent professional appraiser and supported by a written
explanation of the differences.
(25) "Mean sea level" means, for purposes of the
National Flood Insurance Program, the Na~ional Geodetic Vertical
Datum (NGVD) of 1929 or other datum, to which base flood
elevations shown on a conununity's Flood Insurance Rate Map are
referenced.
(26) "New construction", for floodplain management
purposes, means structures for which the "start of construction"
conunenced on or after the effective date of floodplain
management regulations adopted by this community, and includes
any subsequent improvements to such structures.
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(27) " Person" means an individual
partnership, association or corporation,
aforementioned groups, or the State of
agencies or political subdivisions.
or his agent, firm,
or agent of the
California or its
(28) "Recreational vehicle" means a vehicle which:
(A) Is built on a single chassis;
(B) Measures 400 square feet or less at its argest or
widest horizontal projection;
(C) Is designed to be self-propelled or permanently
towable by a small truck;
(D) Is designed primarily not for use as a permanent
dwelling but as temporary living quarters for recreational,
seasonal use camping or travel; and
(E) Incorporates a vehicle that is defined by the
State of California as a camp trailer, camper, fifth-wheel
travel trailer, or house car.
(29) "Remedy a violation" means to bring the structure
or other development into compliance with the State of
California or local floodplain management regulations, or, if
this is not possible, to reduce the impacts of its
noncompliance. Ways that impacts may be reduced include
protecting the structure Or other .affected development from
flood damages, implementing the enforcement provisions of this
chapter or otherwise deterring future similar violations, or
reducing federal or State of California financial exposure with
regard to the structure or other development.
(30) "Riverine" means relating to, formed by, or
resembling a river (including tributaries), stream, or brook.
(31) "Sand dunes" means naturally occurring
accumulations of sand in ridges or mounds landward of the beach.
(32) "Special flood hazard area (SFHA)" means an area
having special flood or flood-related erosion hazards, and shown
on the Flood Insurance Rate Map as Zone A, AO, A1 -A30, AE, AH,
V1 V30, VE or V.
(33) "Start of construction" includes substantial
improvement and other proposed new development, and means the
date on which the building permit was issued, provided the
actual start of construction, repair, reconstruction,
rehabi1i tation, addition, placement, or other improvement
commenced wi thin 180 days from the date of issuance of the
permit. The actual start means either the first placement of
permanent construction of a structure on a site, such as the
pouring of slab or footings, the installation of piles, the
construction of columns, or any work beyond the stage of
excavation; or the placement of a manufactured home on a
foundation. Permanent construction does not include land
preparation, such as clearing, grading and filling; nor does it
include the installation of streets and/or walkways; nor does it
include excavation for a basement, footings, piers, or
foundations or the erection of temporary forms; nor does it
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include the installation on the property of accessory buildings,
such as garages or sheds not occupied as dwelling units or not
part of the main structure. For a substantial improvement, the
actual start of construction means the first alteration of any
wall, ceiling, floor, or other part of a structure, whether or
not that alteration affects the external dimensions of the
structure.
(34) "Structure" means a walled and roofed building,
including but not limited to a gas or liquid storage tank, that
is principally above ground, as well as a manufactured home.
(35) "Substantial damage" means damage of any origin
sustained by a structure, whereby the cost of restoring the
structure to its original damage-free condition would equal or
exceed fifty percent of the market value of the structure before
the damage occurred.
(36) "Substantial improvement" means any
reconstruction, rehabilitation, addition, or other proposed new
development of a structure, the cost of which equals or exceeds
fifty percent of the market value of the structure before the
start of construction of the improvement. This term includes a
structure which has incurred substantial damage, regardless of
the actual repair work to be performed.
The term shall not include:
(A) Any project, or any portion of a project, for
improvement of a structure undertaken in response to a finding
by the local code enforcement official that there are existing
violations of State of California or local health, sanitary, or
safety code specifications which render the structure unfit for
human occupanCYi or
(B) Any alteration of an historic structure, provided
that the alteration will not result in the termination of a
structurets continued designation as an historic structure: or
(C) Any project, or any portion of a project, for
improvement of a structure that is required to comply with the
Americans with Disabilities Act of 1990 (42 U.S.C. Section 12101
et. seq.) .
(37) "Variance" means a grant of relief from the
requirements of this chapter which permits construction in a
manner that would otherwise be prohibited by this chapter.
(38) IIViolationll means the failure of a structure or
other development to be fully compliant with the communityt s
floodplain management regulations. A structure or other
development without the elevation certificate, other
certifications, or other evidence of compliance required in this
chapter is presumed to be in violation until such time as that
documentation is provided.
SECTION 2. Section 16.52.130 (Standards of Construction)
of Chapter 16.52 (Flood Hazard Regulations), Title 16 [Building
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Regulations] of the Palo Alto Municipal Code is hereby amended
to read as follows:
16.52.130 Standards of construction.
In all areas of special flood hazards the following
standards are required:
(a) Anchoring.
(1) All new construction and substantially improved
structures shall be anchored to prevent flotation, collapse or
lateral movement of the structure resulting from hydrodynamic
and hydrostatic loads, including the effects of buoyancy.
(2) All manufactured homes shall meet the anchoring
standards of Section 16.52.160.
(b) Construction Materials and Methods.
(1) All new construction and substantially improved
structures shall be constructed with flood-resistant materials
as specified in applicable Federal Emergency Management Agency
technical bulletins, including but not limited to TB 2-93, and
utility equipment resistant to flood damage.
(2) All new construction and substantially improved
structures shall be constructed using methods and practices that
minimize flood damage.
(3) All new construction and substantially improved
structures shall be constructed with electrical, heating,
ventilation, plumbing and air conditioning equipment and other
service facilities that are designed and/or located so as to
prevent water from entering or accumulating within the
components during conditions of flooding.
(4) Require within Zones AH or AO, adequate drainage
paths around structures on slopes to guide floodwaters around
and away from proposed structures.
(c) Elevation and Floodproofing.
(1) In residential new construction and substantial
improvement of any residential structure, the lowest floor,
including basement:
(A) In an AO zone, shall be elevated above the highest
adjacent grade to a height equal to or exceeding the depth
number specified in feet on the Flood Insurance Rate Map, or
elevated at least two feet above the highest adjacent grade if
no depth number is specifiedi
(B) In an A zone, shall be elevated at least one foot
above the highest adjacent gradei or
(C) In all other zones, shall be elevated to or above
the base flood elevation.
Upon the completion of the structure, the elevation of
the lowest floor, including basement, shall be certified by a
registered professional engineer or surveyor, and verified by a
community official to be properly elevated. Such certification
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and verification shall be provided to the floodplain
administrator.
(2) Nonresidential new construction and any
substantially improved nonresidential structure shall either be
elevated to conform with subdivision (1) of this subsection or,
together with attendant utility and sanitary facilities:
(A) Shall be floodproofed below the minimum elevation
required in subdivision (1) above so that the structure is
watertight with walls substantially impermeable to the passage
of waterj
(B) Shall possess structural components capable of
resisting hydrostatic and hydrodynamic loans and effects of
buoyancy; and
(C) Shall be certified by a registered professional
engineer that the standards of this subdivision are satisfied.
The certification shall be provided to the floodplain
administrator.
(3) All new construction and substantially improved
structures, with fully enclosed areas below the lowest floor
(excluding basements) that are usable solely for the parking of
vehicles, building access or storage, and which are subject to
flooding shall be designed to automatically equalize hydrostatic
flood forces on exterior walls by allowing for the entry and
exit of floodwaters. Designs for meeting this requirement shall
comply with the guidelines set forth in the applicable Federal
Emergency Management Agency technical bulletins, including but
not limited to TB 1 93 and TB 7-93, and shall meet or exceed the
following minimum criteria:
(A) Possess a minimum of two openings with a total net
area of not less than one square inch for every square foot of
enclosed area subject to flooding. The bottom of all openings
shall be no higher than one foot above grade. Openings may be
equipped with screens, louvers, valves or other coverings or
devices provided that they permit the automatic entry and exit
of floodwatersj or
(B) Be certified by a registered professional engineer
or architect.
(4) Manufactured homes shall also meet the standard in
Section 16.52.160.
(d) Existing Residential Below Grade Subfloor Crawl
Spaces. Notwithstanding the provisions of subsection (c) (1) for
existing residential structures, existing below-grade subfloor
crawl spaces shall be allowed to remain beneath substantially
improved structures provided all other standards of construction
set forth in section 16.52.130 and the following conditions are
met:
(1) The lowest floor of the living space of the
existing structure is at or above the elevation required under
subsection (c) above;
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(2) The below-grade crawl space shall be backfilled
to the maximum extent possible without violating Uniform
Building Code requirements for minimum crawl space height;
(3) The crawl space grade is not more than two feet
below the lowest adjacent grade outside the foundation;
(4) The height of the crawl space, measured from the
interior grade of the crawl space to the top of the foundation
wall, does not exceed four feet;
(5) There is an adequate drainage system capable of
removing floodwaters from the interior area of the crawl space
within seventy-two (72) hours after the flood event; and
(6) The expected velocity of the floodwaters at the
site does not exceed five feet per second.
(e) Prohibition of Residential Basement Construction.
(I) For residential structures located wi thin a
Special Flood Hazard Area:
(A) No new basements shall be constructed; and
(B) No existing basements shall be expanded.
SECTION 3. The Council finds that this project is
exempt under the California Environmental Quality Act as a minor
alteration in land use limitations in an area with an average
slope of less than 20% which does not result in any changes in
land use or density. (CEQA Guideline Section 15305) and,
therefore no environment impact assessment is necessary.
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SECTION 4. This ordinance shall be effective on the
thirty-f rst day after the date of its adoption.
INTRODUCED: April 12, 2004
PASSED: May 3, 2004
AYES: BEECHAM, BURCH, CORDELL, FREEMAN, KISHIMOTO, KLEINBERG,
MOSSAR, OJAKIAN
NOES:
ABSENT: MORTON
ABSTENTIONS:
A~: .. ~ . A M..A .9
CrtYC'ierk -iJ-Mayor
~'~City Attorney
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