The Legislature of the state of California has in Government
Code Sections 65302, 65560, and 65800 conferred upon local governments
the authority to adopt regulations designed to promote the public
health, safety, and general welfare of its citizenry. Therefore, the
city council of San Bruno hereby adopts the following floodplain management
regulations.
(Ord. 1870 § 2, 2019)
A.
The
flood hazard areas of the city of San Bruno are subject to periodic
inundation which may result in loss of life and property, health and
safety hazards, disruption of commerce and governmental services,
extraordinary public expenditures for flood protection and relief,
and impairment of the tax base, all of which adversely affect the
public health, safety, and general welfare.
B.
These
potential flood losses are caused by uses that are inadequately elevated,
flood proofed, or protected from flood damage. The cumulative effect
of obstructions in areas of special flood hazards which increase flood
heights and velocities also contributes to flood losses.
(Ord. 1870 § 2, 2019)
It is the purpose of this chapter to promote the public health,
safety, and general welfare, and to minimize public and private losses
due to flood conditions in specific areas by legally enforceable regulations
applied uniformly throughout the community to all publicly and privately
owned land within specific areas. These regulations are designed to:
A.
Protect
human life and health;
B.
Minimize
expenditure of public money for costly flood control projects;
C.
Minimize
the need for rescue and relief efforts associated with flooding generally
undertaken at the expense of the general public;
D.
Minimize
prolonged business interruptions;
E.
Minimize
damage to public facilities and utilities such as water and gas mains;
electric, telephone and sewer lines; and streets and bridges located
in areas of special flood hazard;
F.
Help
maintain a stable tax base by providing for the sound use and development
of areas of special flood hazard so as to minimize future blighted
areas caused by flood damage;
G.
Ensure
that potential buyers are notified that property is in an area of
special flood hazard; and
H.
Ensure
that those who occupy the areas of special flood hazard assume responsibility
for their actions.
(Ord. 1870 § 2, 2019)
In order to accomplish its purposes, this chapter includes regulations
to:
A.
Restrict
or prohibit uses which are dangerous to health, safety, and property
due to water or erosion hazards, or which result in damaging increases
in erosion or flood heights or velocities;
B.
Require
that uses vulnerable to floods, including facilities which serve such
uses, be protected against flood damage at the time of initial construction;
C.
Control
the alteration of natural floodplains, stream channels, and natural
protective barriers, which help accommodate or channel floodwaters;
D.
Control
filling, grading, dredging, and other development which may increase
flood damage; and
E.
Prevent
or regulate the construction of flood barriers which will unnaturally
divert floodwaters or which may increase flood hazards in other areas.
(Ord. 1870 § 2, 2019)
Unless specifically defined below, words or phrases used in
this chapter shall be interpreted so as to give them the meaning they
have in common usage and to give this chapter its most reasonable
application.
See "Special flood hazard area."
means a structure that is either:
means a use which is incidental and subordinate to the principal
use of the parcel of land on which it is located.
means a request for a review of the floodplain administrator's
interpretation of any provision of this chapter.
means the floodplain management regulations appeals board
who reviews an appeal of the provisions of this chapter. This board
consists of the public services director, community and economic development
director, and the community services director.
means a designated AO or AH Zone on the Flood Insurance Rate
Map (FIRM). 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. Such flooding
is characterized by ponding or sheet flow.
See "Special flood hazard area."
means a flood which has a one percent chance of being equaled
or exceeded in any given year (also called the "one-hundred-year flood").
Base flood is the term used throughout this chapter.
means the elevation shown on the Flood Insurance Rate Map
for Zones AE, AH, A1-30, VE and V1-V30 that indicates the water surface
elevation resulting from a flood that has a one-percent or greater
chance of being equaled or exceeded in any given year.
means any area of the building having its floor subgrade,
i.e., below ground level, on all sides.
See "Structure."
means the city of San Bruno, including its elected and appointed
officials and employees charged with duties and responsibilities pursuant
to this chapter.
means any man-made change to improved or unimproved real
estate, including, but not limited to, buildings or other structures,
mining, dredging, filling, grading, paving, excavation or drilling
operations or storage of equipment or materials.
means the advance or infringement of uses, plant growth,
fill, excavation, buildings, permanent structures or development into
a floodplain which may impede or alter the flow capacity of a flood-plain.
means a manufactured home park or subdivision for which the
construction of facilities for servicing the lots on which the manufactured
homes are to be affixed (including, at a minimum, the installation
of utilities, the construction of streets, and either final site grading
or the pouring of concrete pads) is completed before April 11, 2019.
means the preparation of additional sites by the construction
of facilities for servicing the lots on which the manufactured homes
are to be affixed (including the installation of utilities, the construction
of streets, and either final site grading or the pouring of concrete
pads).
means:
A general and temporary condition of partial or complete inundation
of normally dry land areas from the overflow of inland or tidal waters;
the unusual and rapid accumulation or runoff of surface waters from
any source; and/or mudslides (i.e., mudflows); and
The condition resulting from flood-related erosion.
means the official map on which the Federal Emergency Management
Agency or Federal Insurance Administration has delineated both the
areas of special flood hazards and the floodway.
means the official map on which the Federal Emergency Management
Agency or Federal Insurance Administration has delineated both the
areas of special flood hazards and the risk premium zones applicable
to the community.
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.
means any land area susceptible to being inundated by water
from any source (see "Flooding").
is the community official (chief building official) designated
by title to administer and enforce the floodplain management regulations.
means the operation of an overall program of corrective and
preventive measures for reducing flood damage and preserving and enhancing,
where possible, natural resources in the floodplain, including, but
not limited to, emergency preparedness plans, flood control works,
floodplain management regulations, and open space plans.
means this ordinance and other zoning ordinances, subdivision
regulations, building codes, health regulations, special purpose ordinances
(such as grading and erosion control) and other application of police
power which control development in flood-prone areas. This term describes
federal, state or local regulations in any combination thereof which
provide standards for preventing and reducing flood loss and damage.
means any combination of structural and nonstructural additions,
changes, or adjustments to structures which reduce or eliminate flood
damage to real estate or improved real property, water and sanitary
facilities, structures, and their contents.
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. Also referred to as "regulatory floodway."
is that area of the floodplain on either side of the "regulatory
floodway" where encroachment may be permitted.
as related to Section 11.40.090 of this chapter, means that the variance granted must not cause fraud on or victimization of the public. In examining this requirement, the city will consider the fact that every newly constructed building adds to government responsibilities and remains a part of the community for fifty to one hundred years. Buildings that are permitted to be constructed below the base flood elevation are subject to increased risk of damage from floods, while future owners of the property and the community as a whole are subject to all the costs and risks that those increased flood damages bring. In addition, future owners may purchase the property, unaware that it is subject to potential flood damage, and can be insured only at very high flood insurance rates.
means a use which cannot perform its intended purpose 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 ship building and ship repair facilities, and does not include long-term storage or related manufacturing
facilities.
is the local governing unit, i.e., county or municipality
that is empowered to adopt and implement regulations to provide for
the public health, safety and general welfare of its citizenry.
as related to Section 11.40.090 of this chapter means the exceptional hardship that would result from a failure to grant the requested variance. The variance shall be exceptional, unusual, and peculiar to the property involved. Mere economic or financial hardship alone is not exceptional. Inconvenience, aesthetic considerations, physical handicaps, personal preferences, or the disapproval of one's neighbors likewise cannot, as a rule, qualify as an exceptional hardship. All of these problems can be resolved through other means without granting a variance, even if the alternative is more expensive, or requires the property owner to build elsewhere or put the parcel to a different use than originally intended.
means the highest natural elevation of the ground surface
prior to construction next to the proposed walls of a structure.
means any structure that is:
Listed individually in the National Register of Historic Places
(a listing maintained by the Department of Interior) or preliminarily
determined by the Secretary of the Interior as meeting the requirements
for individual listing on the National Register;
Certified or preliminarily determined by the Secretary of the
Interior as contributing to the historical significance of a registered
historic district or a district preliminarily determined by the Secretary
to qualify as a registered historic district;
Individually listed on a state inventory of historic places
in states with historic preservation programs which have been approved
by the Secretary of Interior; or
Individually listed on a local inventory of historic places
in communities with historic preservation programs that have been
certified either by an approved state program as determined by the
Secretary of the Interior or directly by the Secretary of the Interior
in states without approved programs.
means a man-made structure, usually an earthen embankment,
designed and constructed in accordance with sound engineering practices
to contain, control or divert the flow of water so as to provide protection
from temporary flooding.
means a flood protection system which consists of a levee,
or levees, and associated structures, such as closure and drainage
devices, which are constructed and operated in accord with sound engineering
practices.
means the lowest floor of the lowest enclosed area, including
basement (see "Basement" definition).
An unfinished or flood resistant enclosure below the lowest
floor that is usable solely for parking of vehicles, building access
or storage in an area other than a basement area, is not considered
a building's lowest floor provided it conforms to applicable non-elevation
design requirements, including, but not limited to:
The flood openings standard in Section 11.40.080(A)(3)(C);
The anchoring standards in Section 11.40.080(A)(1);
The construction materials and methods standards in Section
11.40.080(A)(2); and
The standards for utilities in Section 11.40.080(B).
For residential structures, all subgrade enclosed areas are
prohibited as they are considered to be basements (see "Basement"
definition). This prohibition includes below-grade garages and storage
areas.
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 attached to the required utilities.
The term "manufactured home" does not include a "recreational vehicle."
means a parcel (or contiguous parcels) of land divided into
two or more manufactured home lots for rent or sale.
is defined in the city of San Bruno substantial damage/improvement
procedures. See Section 11.40.070(B)(2)(a).
means, for purposes of the National Flood Insurance Program,
the National Geodetic Vertical Datum (NGVD) of 1929, North American
Vertical Datum (NAVD) of 1988, or other datum, to which base flood
elevations shown on a community's Flood Insurance Rate Map are referenced.
for floodplain management purposes, means structures for
which the "start of construction" commenced on or after April 11,
2019, and includes any subsequent improvements to such structures.
means a manufactured home park or subdivision for which the
construction of facilities for servicing the lots on which the manufactured
homes are to be affixed (including at a minimum, the installation
of utilities, the construction of streets, and either final site grading
or the pouring of concrete pads) is completed on or after April 11,
2019.
includes, but is not limited to, any dam, wall, wharf, embankment,
levee, dike, pile, abutment, protection, excavation, channelization,
bridge, conduit, culvert, building, wire, fence, rock, gravel, refuse,
fill, structure, vegetation or other material in, along, across or
projecting into any watercourse which may alter, impede, retard or
change the direction and/or velocity of the flow of water, or due
to its location, its propensity to snare or collect debris carried
by the flow of water, or its likelihood of being carried downstream.
or "100-year flood." See "Base flood."
means a defect in a community's floodplain management regulations
or administrative procedures that impairs effective implementation
of those floodplain management regulations.
as related to Section 11.40.090 of this chapter, means that the granting of a variance must not result in anything which is injurious to safety or health of an entire community or neighborhood, or any considerable number of persons, or unlawfully obstructs the free passage or use, in the customary manner, of any navigable lake, or river, bay, stream, canal, or basin.
means a vehicle which is:
Built on a single chassis;
Four hundred square feet or less when measured at the largest
horizontal projection;
Designed to be self-propelled or permanently towable by a light-duty
truck; and
Designed primarily not for use as a permanent dwelling but as
temporary living quarters for recreational, camping, travel, or seasonal
use.
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.
means to bring the structure or other development into compliance
with state 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 the ordinance or otherwise deterring future similar
violations, or reducing state or federal financial exposure with regard
to the structure or other development.
means relating to, formed by, or resembling a river (including
tributaries), stream, brook, etc.
means an area in the floodplain subject to a one percent
or greater chance of flooding in any given year. It is shown on an
FHBM or FIRM as Zone A, AO, A1-A30, AE, A99, or, AH.
includes substantial improvement and other proposed new development
and means the date the building permit was issued, provided the actual
start of construction, repair, reconstruction, rehabilitation, addition,
placement, or other improvement was within one hundred eighty days
from the date 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 manufacture 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 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 structural part of a building, whether or not that alteration
affects the external dimensions of the building.
means a walled and roofed building that is principally above
ground; this includes a gas or liquid storage tank or a manufactured
home.
means damage of any origin sustained by a structure whereby
the cost of restoring the structure to its before damaged condition
would equal or exceed fifty percent of the market value of the structure
before the damage occurred.
means any reconstruction, rehabilitation, addition, or other
improvement 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 structures which
have incurred "substantial damage," regardless of the actual repair
work performed. The term does not, however, include either:
Any project for improvement of a structure to correct existing
violations or state or local health, sanitary, or safety code specifications
which have been identified by the local code enforcement official
and which are the minimum necessary to assure safe living conditions;
or
Any alteration of a "historic structure," provided that the
alteration will not preclude the structure's continued designation
as a "historic structure."
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.
means the failure of a structure or other development to
be fully compliant with this chapter. 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.
means the height, in relation to the National Geodetic Vertical
Datum (NGVD) of 1929, North American Vertical Datum (NAVD) of 1988,
or other datum, of floods of various magnitudes and frequencies in
the floodplains of coastal or riverine areas.
means a lake, river, creek, stream, wash, arroyo, channel
or other topographic feature on or over which waters flow at least
periodically. Watercourse includes specifically designated areas in
which substantial flood damage may occur.
(Ord. 1870 § 2, 2019; Ord. 1927 § 2, 2022)
A.
Lands
to Which this Chapter Applies. This chapter shall apply to all areas
of special flood hazards within the jurisdiction of the city of San
Bruno.
B.
Basis
for Establishing the Areas of Special Flood Hazard. The areas of special
flood hazard identified by the Federal Emergency Management Agency
(FEMA) in the "Flood Insurance Study (FIS) for San Mateo County, California
and Incorporated Areas" dated October 16, 2012, with accompanying
Flood Insurance Rate Maps (FIRMs) and Flood Boundary and Floodway
Maps (FBFMs), dated October 16, 2012, and all subsequent amendments
and/or revisions, are hereby adopted by reference and declared to
be a part of this chapter. This does not limit the city's right to
challenge and appeal future revisions to the FIRM. This FIS and attendant
mapping is the minimum area of applicability of this chapter and may
be supplemented by studies for other areas which allow implementation
of this chapter and which are recommended to the city of San Bruno
city council by the floodplain administrator. The study, FIRMs and
FBFMs are on file at the city of San Bruno.
C.
Compliance.
No structure or land shall hereafter be constructed, located, extended,
converted, or altered without full compliance with the terms of this
chapter and other applicable regulations. Violation of the requirements
(including violations of conditions and safeguards) shall constitute
a misdemeanor. Nothing herein shall prevent the city from taking such
lawful action as is necessary to prevent or remedy any violation.
D.
Abrogation
and Greater Restrictions. This chapter is not intended to repeal,
abrogate, or impair any existing easements, covenants, or deed restrictions.
However, where this chapter and another ordinance, easement, covenant,
or deed restriction conflict or overlap, whichever imposes the more
stringent restrictions shall prevail.
F.
Warning
and Disclaimer of Liability. The degree of flood protection required
by this chapter is considered reasonable for regulatory purposes and
is based on scientific and engineering considerations. Larger floods
can and will occur on rare occasions. Flood heights may be increased
by man-made or natural causes. This chapter does not imply that land
outside the areas of special flood hazards or uses permitted within
such areas will be free from flooding or flood damages. This chapter
shall not create liability on the part of the city, the state of California,
or the Federal Emergency Management Agency, for any flood damages
that result from reliance on this chapter or any administrative decision
lawfully made hereunder.
(Ord. 1870 § 2, 2019)
A.
Designation
of the Floodplain Administrator. The chief building official is hereby
appointed to administer, implement, and enforce this chapter by granting
or denying development permits in accordance with its provisions.
B.
Duties
and Responsibilities of the Floodplain Administrator. The duties and
responsibilities of the floodplain administrator shall include, but
not be limited to, the following:
1.
Permit
Review. Reviews all development permits to determine:
a.
Permit requirements of this chapter have been satisfied, including
determination of substantial improvement and substantial damage of
existing structures;
b.
All other required state and federal permits have been obtained;
c.
The site is reasonably safe from flooding;
d.
The proposed development does not adversely affect the carrying capacity
of areas where base flood elevations have been determined but a floodway
has not been designated. This means that the cumulative effect of
the proposed development when combined with all other existing and
anticipated development will not increase the water surface elevation
of the base flood more than one foot at any point within the city
of San Bruno; and
e.
All letters of map revision (LOMRs) for flood control projects are
approved prior to the issuance of building permits. Building permits
must not be issued based on conditional letters of map revision (CLOMRs).
Approved CLOMRs allow construction of the proposed flood control project
and land preparation as specified in the "start of construction" definition.
2.
Development
of Substantial Improvement and Substantial Damage Procedures.
a.
Using FEMA publication FEMA 213, "Answers to Questions About Substantially
Damaged Buildings," develop detailed procedures for identifying and
administering requirements for substantial improvement and substantial
damage, to include defining "market value."
b.
Assure procedures are coordinated with other departments/divisions
and implemented by community staff.
3.
Review, Use and Development of Other Base Flood Data. When base flood elevation data has not been provided in accordance with Section 11.40.060(B), the floodplain administrator shall obtain, review, and reasonably utilize any base flood elevation and floodway data available from a federal or state agency, or other source, in order to administer Section 11.40.080. NOTE: A base flood elevation may be obtained using one of two methods from the FEMA publication, FEMA 265, "Managing Floodplain Development in Approximate Zone A Areas – A Guide for Obtaining and Developing Base (100-year) Flood Elevations" dated July 1995.
4.
Notification
of Other Agencies.
a.
Alteration or Relocation of a Watercourse.
i.
Notify adjacent communities and the California Department of Water
Resources prior to alteration or relocation;
ii.
Submit evidence of such notification to the Federal Emergency Management
Agency; and
iii.
Assure that the flood carrying capacity within the altered or
relocated portion of said watercourse is maintained.
b.
Base Flood Elevation Changes Due to Physical Alterations.
i.
Within six months of information becoming available or project completion,
whichever comes first, the floodplain administrator shall submit or
assure that the permit applicant submits technical or scientific data
to FEMA for a letter of map revision (LOMR).
ii.
All LOMRs for flood control projects are approved prior to the issuance
of building permits. Building permits must not be issued based on
conditional letters of map revision (CLOMRs). Approved CLOMRs allow
construction of the proposed flood control project and land preparation
as specified in the "start of construction" definition. Such submissions
are necessary so that upon confirmation of those physical changes
affecting flooding conditions, risk premium rates and floodplain management
requirements are based on current data.
c.
Changes in Corporate Boundaries. Notify FEMA in writing whenever
the corporate boundaries have been modified by annexation or other
means and include a copy of a map of the community clearly delineating
the new corporate limits.
5.
Documentation
of Floodplain Development. Obtain and maintain for public inspection
and make available as needed the following:
a.
Certification required by Section 11.40.080(A)(3)(a) and Section 11.40.080(D) (lowest floor elevations);
b.
Certification required by Section 11.40.080(A)(3)(b) (elevation or
floodproofing of nonresidential structures);
c.
Certification required by Section 11.40.080(A)(3)(c) (wet floodproofing
standard);
d.
Certification required by Sections 11.40.080(C)(1)(c) (subdivisions
and other proposed development standards);
e.
Certification required by Section 11.40.080(F)(2) (floodway encroachments);
and
f.
Maintain a record of all variance actions, including justification
for their issuance, and report such variances issued in its biennial
report submitted to the Federal Emergency Management Agency.
6.
Map Determination. Make interpretations where needed, as to the exact location of the boundaries of the areas of special flood hazard, where there appears to be a conflict between a mapped boundary and actual field conditions. The person contesting the location of the boundary shall be given a reasonable opportunity to appeal the interpretation as provided in subsection D of this section.
7.
Remedial Action. Take action to remedy violations of this chapter as specified in Section 11.40.060(C).
8.
Biennial
Report. Complete and submit biennial report to FEMA.
9.
Planning.
Assure community's general plan is consistent with floodplain management
objectives herein.
C.
Development Permit. A development permit shall be obtained before any construction or other development, including manufactured homes, within any area of special flood hazard established in Section 11.40.060(B). Application for a development permit shall be made on forms furnished by the city. The applicant shall provide the following minimum information:
1.
Plans
in duplicate, drawn to scale, showing:
a.
Location, dimensions, and elevation of the area in question, existing
or proposed structures, storage of materials and equipment and their
location;
b.
Proposed locations of water supply, sanitary sewer, and other utilities;
c.
Grading information showing existing and proposed contours, any proposed
fill, and drainage facilities;
d.
Location of the regulatory floodway when applicable;
e.
Base flood elevation information as specified in Section 11.40.060(B) or Section 11.40.070(B)(3);
f.
Proposed elevation in relation to mean sea level, of the lowest floor
(including basement) of all structures; and
g.
Proposed elevation in relation to mean sea level to which any nonresidential
structure will be floodproofed, as required in Section 11.40.080(A)(3)(b)
of this chapter and detailed in FEMA Technical Bulletin TB 3-93.
2.
Certification
from a registered civil engineer or architect that the nonresidential
floodproofed building meets the floodproofing criteria in Section
11.40.080(A)(3)(b).
3.
For
a crawlspace foundation, location and total net area of foundation
openings as required in Section 11.40.080(A)(3)(c) of this chapter
and detailed in FEMA Technical Bulletins 1-93 and 7-93.
4.
Description
of the extent to which any watercourse will be altered or relocated
as a result of proposed development.
5.
All
appropriate certifications listed in subsection (B)(5) of this section.
D.
Appeals.
The city's appeals board shall hear and decide appeals when it is
alleged there is an error in any requirement, decision, or determination
made by the floodplain administrator in the enforcement or administration
of this chapter.
(Ord. 1870 § 2, 2019)
A.
Standards
of Construction. In all areas of special flood hazards the following
standards are required:
1.
Anchoring.
All new construction and substantial improvements of structures, including
manufactured homes, shall be adequately anchored to prevent flotation,
collapse or lateral movement of the structure resulting from hydrodynamic
and hydrostatic loads, including the effects of buoyancy.
2.
Construction
Materials and Methods. All new construction and substantial improvements
of structures, including manufactured homes, shall be constructed:
a.
With flood resistant materials, and utility equipment resistant to
flood damage for areas below the base flood elevation;
b.
Using methods and practices that minimize flood damage; and
c.
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;
d.
Within Zone AH, so that there are adequate drainage paths around
structures on slopes to guide flood waters around and away from proposed
structures.
3.
Elevation
and Floodproofing.
a.
Residential Construction. All new construction or substantial improvements
of residential structures in AE Zones shall have the lowest floor,
including basement: 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 civil
engineer or licensed land surveyor, and verified by the community
building inspector to be properly elevated. Such certification and
verification shall be provided to the floodplain administrator.
b.
Nonresidential Construction. All new construction or substantial
improvements of nonresidential structures shall either be elevated
to conform to Section 11.40.080(A)(3)(a) or:
i.
Be floodproofed, together with attendant utility and sanitary facilities,
below the elevation recommended under Section 11.40.080(A)(3)(a),
so that the structure is watertight with walls substantially impermeable
to the passage of water;
ii.
Have structural components capable of resisting hydrostatic and hydrodynamic
loads and effects of buoyancy; and
iii.
Be certified by a registered civil engineer or architect that
the standards of Section 11.40.080(A)(3)(b)(i) and 11.40.080(A)(3)(b)(ii)
are satisfied. Such certification shall be provided to the floodplain
administrator.
c.
Flood Openings. All new construction and substantial improvements
of structures with fully enclosed areas below the lowest floor (excluding
basements) that are usable solely for 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 floodwater. Designs for meeting
this requirement must meet the following minimum criteria:
i.
For nonengineered openings:
(A)
Have a minimum of two openings on different sides having a total
net area of not less than one square inch for every square foot of
enclosed area subject to flooding;
(B)
The bottom of all openings shall be no higher than one foot
above grade;
(C)
Openings may be equipped with screens, louvers, valves or other
coverings or devices provided that they permit the automatic entry
and exit of floodwater; and
(D)
Buildings with more than one enclosed area must have openings
on exterior walls for each area to allow flood water to directly enter;
or
ii.
Be certified by a registered civil engineer or architect.
d.
Manufactured Homes. See Section 11.40.080(D).
e.
Garages and Low Cost Accessory Structures.
i.
Attached garages.
(A)
A garage attached to a residential structure, constructed with
the garage floor slab below the BFE, must be designed to allow for
the automatic entry of flood waters. See Section 11.40.080(A)(3)(c).
Areas of the garage below the BFE must be constructed with flood resistant
materials. See Section 11.40.080(A)(2).
(B)
A garage attached to a nonresidential structure must meet the
above requirements or be dry floodproofed. For guidance on below grade
parking areas, see FEMA Technical Bulletin TB-6.
ii.
Detached garages and accessory structures.
(A)
"Accessory structures" used solely for parking (two-car detached garages or smaller) or limited storage (small, low-cost sheds), as defined in Section 11.40.050, may be constructed such that its floor is below the base flood elevation (BFE), provided the structure is designed and constructed in accordance with the following requirements:
(1)
Use of the accessory structure must be limited to parking or
limited storage;
(2)
The portions of the accessory structure located below the BFE
must be built using flood-resistant materials;
(3)
The accessory structure must be adequately anchored to prevent
flotation, collapse and lateral movement;
(4)
Any mechanical and utility equipment in the accessory structure
must be elevated or floodproofed to or above the BFE;
(5)
The accessory structure must comply with floodplain encroachment provisions in Section 11.40.080(F); and
(6)
The accessory structure must be designed to allow for the automatic
entry of flood waters in accordance with Section 11.40.080(A)(3)(c).
(B)
Detached garages and accessory structures not meeting the above standards must be constructed in accordance with all applicable standards in Section 11.40.080(A).
f.
Crawl Space Construction. This subsection applies to buildings with
crawl spaces up to two feet below grade. Below-grade crawl space construction
in accordance with the requirements listed below will not be considered
basements.
i.
The building must be designed and adequately anchored to resist flotation,
collapse, and lateral movement of the structure resulting from hydrodynamic
and hydrostatic loads, including the effects of buoyancy. Crawl space
construction is not allowed in areas with flood velocities greater
than five feet per second unless the design is reviewed by a qualified
design professional, such as a registered architect or professional
engineer;
ii.
The crawl space is an enclosed area below the BFE and, as such, must
have openings that equalize hydrostatic pressures by allowing for
the automatic entry and exit of floodwaters. For guidance on flood
openings, see FEMA Technical Bulletin 1-93;
iii.
Portions of the building below the BFE must be constructed with
materials resistant to flood damage. This includes not only the foundation
walls of the crawl space used to elevate the building, but also any
joists, insulation, or other materials that extend below the BFE;
iv.
Any building utility systems within the crawl space must be elevated
above BFE or designed so that floodwaters cannot enter or accumulate
within the system components during flood conditions; and
v.
Requirements for all below-grade crawl space construction, in addition
to the above requirements, to include the following:
(A)
The interior grade of a crawl space below the BFE must not be
more than two feet below the lowest adjacent exterior grade (LAG),
shown as D in Figure 3 of Technical Bulletin 11-01;
(B)
The height of the below-grade crawl space, measured from the
interior grade of the crawl space to the top of the crawl space foundation
wall must not exceed four feet (shown as L in Figure 3 of Technical
Bulletin 11-01) at any point;
(C)
There must be an adequate drainage system that removes floodwaters
from the interior area of the crawl space within a reasonable period
of time after a flood event, not to exceed seventy-two hours; and
(D)
The velocity of floodwaters at the site should not exceed five
feet per second for any crawl space. For velocities in excess of five
feet per second, other foundation types should be used.
B.
C.
Standards
for Subdivisions and Other Proposed Development.
1.
All
new subdivisions proposals and other proposed development, including
proposals for manufactured home parks and subdivisions, greater than
fifty lots or five acres, whichever is the lesser, shall:
a.
Identify the special flood hazard areas (SFHA) and base flood elevations
(BFE).
b.
Identify the elevations of lowest floors of all proposed structures
and pads on the final plans.
c.
If the site is filled above the base flood elevation, the following
as-built information for each structure shall be certified by a registered
civil engineer or licensed land surveyor and provided as part of an
application for a Letter of Map Revision based on Fill (LOMR-F) to
the Floodplain Administrator:
2.
All
subdivision proposals and other proposed development shall be consistent
with the need to minimize flood damage.
3.
All
subdivision proposals and other proposed development shall have public
utilities and facilities such as sewer, gas, electrical and water
systems located and constructed to minimize flood damage.
4.
All
subdivisions and other proposed development shall provide adequate
drainage to reduce exposure to flood hazards.
D.
Standards
for Manufactured Homes.
1.
All
manufactured homes that are placed or substantially improved, on sites
located: (1) outside of a manufactured home park or subdivision; (2)
in a new manufactured home park or subdivision; (3) in an expansion
to an existing manufactured home park or subdivision; or (4) in an
existing manufactured home park or subdivision upon which a manufactured
home has incurred "substantial damage" as the result of a flood, shall:
a.
Within Zone AE on the community's Flood Insurance Rate Map, be elevated
on a permanent foundation such that the lowest floor of the manufactured
home is elevated to or above the base flood elevation and be securely
fastened to an adequately anchored foundation system to resist flotation,
collapse, and lateral movement.
2.
All
manufactured homes to be placed or substantially improved on sites
in an existing manufactured home park or subdivision within Zone AH
and AE on the community's Flood Insurance Rate Map that are not subject
to the provisions of subsection (D)(1) will be securely fastened to
an adequately anchored foundation system to resist flotation, collapse,
and lateral movement, and be elevated so that either the:
a.
Lowest floor of the manufactured home is at or above the base flood
elevation; or
b.
Manufactured home chassis is supported by reinforced piers or other
foundation elements of at least equivalent strength that are no less
than thirty-six inches in height above grade. Upon the completion
of the structure, the elevation of the lowest floor including basement
shall be certified by a registered civil engineer or licensed land
surveyor, and verified by the community building inspector to be properly
elevated. Such certification and verification shall be provided to
the floodplain administrator.
E.
Standards
for Recreational Vehicles. All recreational vehicles placed in Zone
AE shall either:
1.
Be
on the site for fewer than one hundred eighty consecutive days; or
2.
Be
fully licensed and ready for highway use. A recreational vehicle is
ready for highway use if it is on its wheels or jacking system, is
attached to the site only by quick disconnect type utilities and security
devices, and has no permanently attached additions; or
3.
Meet the permit requirements of Section 11.40.070(C) of this chapter and the elevation and anchoring requirements for manufactured homes in subsection D.
F.
Floodways.
Since floodways are an extremely hazardous area due to the velocity
of flood waters which carry debris, potential projectiles, and erosion
potential, the following provisions apply:
1.
Until
a regulatory floodway is adopted, no new construction, substantial
development, or other development (including fill) shall be permitted
within Zone AE, unless it is demonstrated that the cumulative effect
of the proposed development, when combined with all other development,
will not increase the water surface elevation of the base flood more
than one foot at any point within the city of San Bruno.
2.
Within
an adopted regulatory floodway, the city of San Bruno shall prohibit
encroachments, including fill, new construction, substantial improvements,
and other development, unless certification by a registered civil
engineer is provided demonstrating that the proposed encroachment
shall not result in any increase in flood levels during the occurrence
of the base flood discharge.
3.
If
subsections (F)(1) and (2) are satisfied, all new construction, substantial
improvement, and other proposed new development shall comply with
all other applicable flood hazard reduction provisions of this section.
(Ord. 1870 § 2, 2019; Ord. 1927 § 2, 2022)
A.
Nature
of Variances. The issuance of a variance is for floodplain management
purposes only. Insurance premium rates are determined by statute according
to actuarial risk and will not be modified by the granting of a variance.
The variance criteria set forth in this section of the chapter are
based on the general principle of zoning law that variances pertain
to a piece of property and are not personal in nature. A variance
may be granted for a parcel of property with physical characteristics
so unusual that complying with the requirements of this chapter would
create an exceptional hardship to the applicant or the surrounding
property owners. The characteristics must be unique to the property
and not be shared by adjacent parcels. The unique characteristic must
pertain to the land itself, not to the structure, its inhabitants,
or the property owners.
B.
Conditions
for Variances.
1.
Generally, variances may be issued for new construction, substantial improvement, and other proposed new development to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, providing that the procedures of Sections 11.40.070 and 11.40.080 of this chapter have been fully considered. As the lot size increases beyond one-half acre, the technical justification required for issuing the variance increases.
2.
Variances may be issued for the repair or rehabilitation of "historic structures" (as defined in Section 11.40.050 of this chapter) upon a determination that the proposed repair or rehabilitation will not preclude the structure's continued designation as an historic structure and the variance is the minimum necessary to preserve the historic character and design of the structure.
3.
Variances
shall not be issued within any mapped regulatory floodway if any increase
in flood levels during the base flood discharge would result.
4.
Variances
shall only be issued upon a determination that the variance is the
"minimum necessary" considering the flood hazard, to afford relief.
"Minimum necessary" means to afford relief with a minimum of deviation
from the requirements of this chapter. For example, in the case of
variances to an elevation requirement, this means the floodplain administrator
need not grant permission for the applicant to build at grade, or
even to whatever elevation the applicant proposes, but only to that
elevation which the floodplain administrator believes will both provide
relief and preserve the integrity of the local ordinance.
5.
Any
applicant to whom a variance is granted shall be given written notice
over the signature of a community official that:
a.
The issuance of a variance to construct a structure below the base
flood level will result in increased premium rates for flood insurance
up to amounts as high as twenty-five dollars for one hundred dollars
of insurance coverage; and
b.
Such construction below the base flood level increases risks to life
and property. It is recommended that a copy of the notice shall be
recorded by the floodplain administrator in the office of the San
Mateo County recorder and shall be recorded in a manner so that it
appears in the chain of title of the affected parcel of land.
6.
The
floodplain administrator will maintain a record of all variance actions,
including justification for their issuance, and report such variances
issued in its biennial report submitted to the Federal Emergency Management
Agency.
C.
Appeal
Board.
1.
In
reviewing appeals of variance decisions, the appeals board shall consider
all technical evaluations, all relevant factors, standards specified
in other sections of this chapter, and the:
a.
Danger that materials may be swept onto other lands to the injury
of others;
b.
Danger of life and property due to flooding or erosion damage;
c.
Susceptibility of the proposed facility and its contents to flood
damage and the effect of such damage on the existing individual owner
and future owners of the property;
d.
Importance of the services provided by the proposed facility to the
community;
e.
Necessity to the facility of a waterfront location, where applicable;
f.
Availability of alternative locations for the proposed use which
are not subject to flooding or erosion damage;
g.
Compatibility of the proposed use with existing and anticipated development;
h.
Relationship of the proposed use to the comprehensive plan and floodplain
management program for that area;
i.
Safety of access to the property in time of flood for ordinary and
emergency vehicles;
j.
Expected heights, velocity, duration, rate of rise, and sediment
transport of the flood waters expected at the site; and
k.
Costs of providing governmental services during and after flood conditions,
including maintenance and repair of public utilities and facilities
such as sewer, gas, electrical, and water system, and streets and
bridges.
2.
Variances
shall only be issued upon a:
a.
Showing of good and sufficient cause;
b.
Determination that failure to grant the variance would result in
exceptional "hardship" to the applicant; and
c.
Determination that the granting of a variance will not result in
increased flood heights, additional threats to public safety, or extraordinary
public expense, create a nuisance (see "Public safety and nuisance"),
cause "fraud and victimization" of the public, or conflict with existing
local laws or ordinances.
3.
Variances
may be issued for new construction, substantial improvement, and other
proposed new development necessary for the conduct of a functionally
dependent use provided that the provisions of subsection (C)(1) through
(C)(4) are satisfied and that the structure or other development is
protected by methods that minimize flood damages during the base flood
and does not result in additional threats to public safety and does
not create a public nuisance.
(Ord. 1870 § 2, 2019)
