The legislature of the state has in the Flood Control Insurance
Act,
Texas Water Code, Section 16.315, as amended, delegated
the responsibility of local governmental units to adopt regulations
designed to minimize flood losses. Therefore, the City Council of
Cedar Park of Travis and Williamson County, Texas does ordain as follows.
(Ordinance CO31-16-02-25-C1 adopted 2/25/16)
(a) The
flood hazard areas of the city, are subject to periodic inundation
which results in loss of life and property, health and safety hazards,
disruption of commerce and governmental services, and extraordinary
public expenditures for flood protection and relief, all of which
adversely affect the public health, safety and general welfare.
(b) These
flood losses are created by the cumulative effect of obstructions
in floodplains which cause an increase in flood heights and velocities,
and by the occupancy of flood hazard areas by uses vulnerable to floods
and hazardous to other lands because they are inadequately elevated,
floodproofed, or otherwise protected from flood damage.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08)
It is the purpose of these regulations to promote the public
health, safety and general welfare and to minimize public and private
losses due to flood conditions in specific areas by provisions designed
to:
(1) Protect
human life and health;
(2) Minimize
expenditure of public money for costly flood control projects;
(3) Minimize
the need for rescue and relief efforts associated with flooding and
generally undertaken at the expense of the general public;
(4) Minimize
prolonged business interruptions;
(5) Minimize
damage to public facilities and utilities such as water and gas mains,
electric, telephone and sewer lines, streets and bridges located in
floodplains;
(6) Help
maintain a stable tax base by providing for the sound use and development
of floodprone areas in such a manner as to minimize future flood blight
areas; and
(7) Insure
the potential buyers are notified that property is in a flood area.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08)
In order to accomplish its purposes, this article uses the following
methods:
(1) Restrict
or prohibit uses that are dangerous to health, safety or property
in times of flood, or cause excessive increases in flood heights or
velocities;
(2) Require
that uses vulnerable to floods, including facilities which serve such
uses, be protected against flood damage at the time of initial construction;
(3) Control
the alteration of natural floodplains, stream channels, and natural
protection barriers, which are involved in the accommodation of floodwaters;
(4) Control
filling, grading, dredging and other development which may increase
flood damage;
(5) Prevent
or regulate the construction of flood barriers which will unnaturally
divert floodwaters or which may increase flood hazards to other lands.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08)
Unless specifically defined below, words or phrases used in
this article shall be interpreted to give them the meaning they have
in common usage and to give this article its most reasonable application.
Alluvial fan flooding.
Flooding occurring on the surface of an alluvial fan or similar
landform which originates at the apex and is characterized by high-velocity
flows, active processes or erosion, sediment transport, and deposition,
and unpredictable flow paths.
Apex.
A point on an alluvial fan or similar landform below which
the flow path of the major stream that formed the fan becomes unpredictable
and alluvial fan flooding can occur.
Appurtenant structure.
A structure which is on the same parcel of property as the
principal structure to be insured and the use of which is incidental
to the use of the principal structure.
Area of shallow flooding.
A designated AO, AH, or VO zone on a community’s flood
insurance rate map (FIRM) with a one-percent change or greater annual
change of flooding to an average depth of one (1) to three (3) feet
where a clearly defined channel does not exist, where the path of
flooding is unpredictable and where velocity flow may be evident.
Such flooding is characterized by ponding or sheet flow.
Area of special flood hazard.
The land in the floodplain within a community subject to
a one-percent or greater chance of flooding in any given year. The
area may be designated as zone A on the flood hazard boundary map
(FHBM). After detailed ratemaking has been completed in preparation
for publication of the FIRM, zone A usually is refined into zones,
A, AE, AH, AO, A1-99, VO, V1-30, VE or V.
Base flood.
The flood having a one-percent chance of being equaled or
exceeded in any given year.
Base flood elevation (BFE).
The elevation shown on the flood insurance rate map (FIRM)
and found in the accompanying flood insurance study (FIS) for zones
A, AE, AH, A1-A30, AR, V1-V30, or VE that indicates the water surface
elevation resulting from the flood that has a 1% chance of equaling
or exceeding that level in any given year - also called the base flood.
Basement.
Any area of the building having its floor subgrade (below
ground level) on all sides.
Breakaway wall.
A wall that is not part of the structural support of the
building and is intended through its design and construction to collapse
under specific lateral loading forces, without causing damage to the
elevated portion of the building or supporting foundation system.
Critical feature.
An integral and readily identifiable part of a flood protection
system, without which the flood protection provided by the entire
system would be compromised.
Development.
Any manmade 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.
Elevated building.
A nonbasement building:
(1)
Built, in the case of a building in zones A1-30, AE, A, A99,
AO, AH, B, C, X and D, to have the top of the elevated floor, or in
the case of a building in zones V1-30, VE or V, to have the bottom
of the lowest horizontal structure member of the elevated floor elevated
above the ground level by means of pilings, columns (post and piers),
or shear walls parallel to the floor of the water; and
(2)
Adequately anchored so as not to impair the structural integrity
of the building during a flood of up to the magnitude of the base
flood. In the case of zones A1-30, AE, A, A99, AO, AH, B, C, X, D,
“elevated building” also includes a building elevated
by means of fill or solid foundation perimeter walls with openings
sufficient to facilitate the unimpeded movement of floodwaters. In
the case of zones V1-30, VE or V, “elevated building”
also includes a building otherwise meeting the definition of “elevated
building,” even though the lower area is enclosed by means of
breakaway walls if the breakaway walls meet the standards of section
60.3(e)(5) of the National Flood Insurance Program regulations.
Existing construction.
For the purposes of determining rates, structures for which
the start of construction commenced before the effective date of the
FIRM or before January 1, 1975, for FIRMs effective before that date.
“Existing construction” may also be referred to as existing
structures.
Existing manufactured home park or subdivision.
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 the effective date of
the floodplain management regulations adopted by a community.
Expansion to an existing manufactured home park or subdivision.
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).
Flood elevation study.
An examination, evaluation and determination of flood hazards
and, if appropriate, corresponding water surface elevations, or an
examination, evaluation and determination of mudslide (i.e., mudflow)
and/or flood-related erosion hazards.
Flood insurance rate map (FIRM).
An official map of a community, on which the Federal Emergency
Management Agency has delineated both the areas of special flood hazards
and the risk premium zones applicable to the community.
Flood insurance study.
The official report provided by the Federal Emergency Management
Agency. The report contains flood profiles, water surface elevation
of the base flood, as well as the flood boundary-floodway map.
Flood or flooding.
A general and temporary condition of partial or complete
inundation of normally dry land areas from:
(1)
The overflow of inland or tidal waters.
(2)
The unusual and rapid accumulation or runoff of surface waters
from any source.
Flood protection system.
Those physical structural works for which funds have been
authorized, appropriated, and expended and which have been constructed
specifically to modify flooding in order to reduce the extent of the
areas within a community subject to a special flood hazard and the
extent of the depths of associated flooding. Such a system typically
includes hurricane tidal barriers, dams, reservoirs, levees or dikes.
These specialized flood modifying works are those constructed in conformance
with sound engineering standards.
Floodplain management.
The operation of an overall program of corrective and preventive
measures for reducing flood damage, including but not limited to,
emergency preparedness plans, flood control works and floodplain management
regulations.
Floodplain management regulations.
Zoning ordinances, subdivision regulations, building codes,
health regulations, special purpose ordinances (such as a floodplain
ordinance, grading ordinance, and erosion control ordinance) and other
applications of police power. The term describes such state or local
regulations, in any combination thereof, which provide standards for
the purpose of flood damage prevention and reduction.
Floodproofing.
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.
Floodway (regulatory floodway).
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
a designated height.
Functionally dependent use.
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, but does not include long-term storage or
related manufacturing facilities.
High adjacent grade.
The highest natural elevation of the ground surface prior
to construction next to the proposed walls of a structure.
Historic structure.
Any structure that is:
(1)
Listed individually in the National Register of Historic Places
(a listing maintained by the Department of the Interior) or preliminary
determined by the Secretary of the Interior as meeting the requirements
for individual listing on the National Register;
(2)
Certified or preliminary determined by the Secretary of the
Interior as contributing to the historical significance of a registered
historic district or a district preliminary determined by the Secretary
[of the interior] to qualify as a registered historic district;
(3)
Individually listed on a state inventory of historic places
in states with historic preservation programs which have been approved
by the Secretary of the Interior; or
(4)
Individually listed on a local inventory of historic places
in communities with historic preservation programs that have been
certified either:
(A)
By an approved state program as determined by the Secretary
of the Interior; or
(B)
Directly by the Secretary of the Interior in states without
approved programs.
Levee.
A manmade 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.
Levee system.
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 accordance with sound engineering
practices.
Lowest floor.
The lowest floor of the lowest enclosed area (including basement).
An unfinished or flood resistant enclosure, 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,
that such enclosure is not built so as to render the structure in
violation of the applicable nonelevation design requirement of section
60.3 of the National Flood Insurance Program regulations.
Manufactured home.
A structure transportable in one (1) or more sections, which
is built on a permanent chassis and is designed for use with or without
a permanent foundation when connected to the required utilities. The
term “manufactured home” does not include a recreational
vehicle.
Mean sea level.
For purposes of the National Flood Insurance Program, the
National 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.
New construction.
For the purpose of determining insurance rates, structures
for which the start of construction commenced on or after the effective
date of an initial FIRM or after December 31, 1974, whichever is later,
and includes any subsequent improvements to such structures. For floodplain
management purposes, “new construction” means structures
for which the start of construction commenced on or after the effective
date of a floodplain management regulation adopted by a community
and includes any subsequent improvements to such structures.
New manufactured home park or subdivision.
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 the effective date
of floodplain management regulations adopted by a community.
Recreational vehicle.
A vehicle which is:
(1)
Built on a single chassis;
(2)
Four hundred (400) square feet or less when measured at the
largest horizontal projections;
(3)
Designed to be self-propelled or permanently towable by a light
duty truck; and
(4)
Designed primarily not for use as a permanent dwelling but as
temporary living quarters for recreational, camping, travel, or seasonal
use.
Regulatory floodway.
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
a designated height.
Riverine.
Relating to, formed by, or resembling a river (including
tributaries), stream, brook, etc.
Start of construction.
For other than new construction or substantial improvements
under the Coastal Barrier Resources Act (Pub. L. 97-348), includes
substantial improvement and means the date the building permit was
issued, provided the actual start of construction, repair, reconstruction,
placement, or other improvement was within one hundred-eighty (180)
days of the permit date. 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 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
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.
Structure.
A walled and roofed building, including a gas or liquid storage
tank, that is principally above ground, as well as a manufactured
home.
Substantial damage.
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 (50) percent of the market value of the structure
before the damage occurred.
Substantial improvement.
Any reconstruction, rehabilitation, addition or other improvement
of a structure, the cost of which equals or exceeds fifty (50) percent
of the market value of the structure before start of construction
of the improvement. This includes structures which have incurred substantial
damage, regardless of the actual repair work performed. The term does
not, however, include either:
(1)
Any project for improvement of a structure to correct existing
violations of state or local health, sanitary, or safety code specifications
that have been identified by the local code enforcement official,
and which are the minimum necessary conditions; or
(2)
Any alteration of a historic structure, provided that the alteration
will not preclude the structure’s continued designation as a
historic structure.
Variance.
A grant of relief to a person from the requirement of this
article when specific enforcement would result in unnecessary hardship.
A variance, therefore, permits construction or development in a manner
otherwise prohibited by this article. (For full requirements see section
60.6 of the National Flood Insurance Program regulations.)
Violation.
The failure of a structure or other development to be fully
compliant with the community’s floodplain management regulations.
A structure or other development without the elevation certificate,
other certifications, or other evidence of compliance required in
section 60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or (e)(5)
[of the National Flood Insurance Program regulations] is presumed
to be in violation until such time as that documentation is provided.
Water surface elevation.
The height, in relation to the National American Vertical
Datum (NAVD) of 1988 (or other datum, where specified), of floods
of various magnitudes and frequencies in the floodplains of coastal
or riverine areas.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08; Ordinance CO31-16-02-25-C1 adopted 2/25/16)
(a) Lands to which this Article applies.
This Article shall
apply to all areas of special flood hazard within the jurisdiction
of the City.
(b) Basis for establishing the areas of special flood hazard.
The areas of special flood hazard identified by the Federal Emergency
Management Agency in the current scientific and engineering report
entitled, “The Flood Insurance Study (FIS) for Williamson County,
Texas, and Incorporated Areas dated September 6, 2008, with accompanying
flood insurance rate maps (FIRMs) dated September 6, 2008,”
as amended, and “The Flood Insurance Study (FIS) for Travis
County, Texas, and Incorporated Areas” dated January 6, 2016
with accompanying flood insurance rate maps (FIRMs) dated January
6, 2016, as amended, are hereby adopted by reference and declared
to be a part of this Article.
(c) Establishment of development permit.
A development permit
shall be required to ensure conformance with the provisions of this
Article.
(d) Compliance.
No structure or land shall hereafter be
located, altered, or have its use changed without full compliance
with the terms of this Article and other applicable regulations.
(e) Abrogation and greater restrictions.
This Article is
not intended to repeal, abrogate, or impair any existing easements,
covenants, or deed restrictions. However, where this Article and another
existing easement, covenant, or deed restriction conflict or overlap,
whichever imposes the more stringent restrictions shall prevail.
(f) Interpretation.
In the interpretation and application
of this Article, all provisions shall be:
(1) Considered as minimum requirements;
(2) Liberally construed in favor of the governing body; and
(3) Deemed neither to limit nor repeal any other powers granted under
state statutes.
(g) Warning and disclaimer of liability.
The degree of flood
protection required by this Article is considered reasonable for regulatory
purposes and is based on scientific and engineering considerations.
On rare occasions greater floods can and will occur and flood heights
may be increased by manmade or natural causes. This Article 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 Article shall not create liability on the part of the community
or any official or employee thereof for any flood damages that result
from reliance on these provisions or any administrative decision lawfully
made thereunder.
(Ordinance CO31-16-02-25-C1 adopted 2/25/16)
(a) Designation of the Floodplain Administrator.
The Director
of Engineering is hereby appointed the Floodplain Administrator to
administer and implement the provisions of this Article and other
appropriate sections of 44 CFR (Emergency Management and Assistance
- National Flood Insurance Program regulations) pertaining to floodplain
management.
(b) Duties and responsibilities of the Floodplain Administrator.
Duties and responsibilities of the Floodplain Administrator
shall include, but not be limited to, the following:
(1) Maintain and hold open for public inspection all records pertaining
to the provisions of this Article.
(2) Review permit application to determine whether proposed building
site, including the placement of manufactured homes, will be reasonably
safe from flooding.
(3) Review, approve or deny all applications for development permits
required by adoption of this Article.
(4) Review permits for proposed development to assure that all necessary
permits have been obtained from those federal, state or local governmental
agencies (including section 404 of the Federal Water Pollution Control
Act Amendments of 1972, 33 U.S.C. 1334) from which prior approval
is required.
(5) Where interpretation is needed as to the exact location of the boundaries
of the areas of special flood hazards (for example, where there appears
to be a conflict between a mapped boundary and actual field conditions)
the Floodplain Administrator shall make the necessary interpretation.
(6) Notify, in riverine situations, adjacent communities and the state
coordinating agency which is the Texas Water Development Board (TWDB),
prior to any alteration or relocation of a watercourse, and submit
evidence of such notification to the Federal Emergency Management
Agency. The Texas Commission on Environmental Quality (TCEQ) must
also be notified.
(7) Assure that the flood carrying capacity within the altered or relocated
portion of any watercourse is maintained.
(8) When base flood elevation data has not been provided in accordance with section
3.03.006(b), the Floodplain Administrator shall obtain, review, and reasonably utilize any base flood elevation data and floodway data available from a federal, state, or other source, in order to administer the provisions of section
3.03.008.
(9) When a regulatory floodway has not been designated, the Floodplain
Administrator must require that no new construction, substantial improvements,
or other development (including fill) shall be permitted within zones
A1-30 and AE on the community’s FIRM, unless it is demonstrated
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 at any point within
the community.
(10) Under the provisions of 44 CFR chapter
1, section 65.12, of the National Flood Insurance Program regulations, a community may approve certain development in zones A1-30, AE, AH, on the community’s FIRM which increases the water surface elevation of the base flood by more than 1 foot, provided that the community first completes all of the provisions required by section 65.12.
(c) Permit procedures.
(1) Application for a development permit shall be presented to the floodplain
administrator on forms furnished by him/her and may include, but not
be limited to, plans in duplicate drawn to scale showing the locations,
dimensions, and elevation of proposed landscape alterations, existing
and proposed structures, and the location of the foregoing in relation
to areas of special flood hazard. Additionally, the following information
is required:
(A) Elevation (in relation to mean sea level), of the lowest floor (including
basement) of all new and substantially improved structures;
(B) Elevation in relation to mean sea level to which any nonresidential
structure shall be floodproofed;
(C) A certificate from a registered professional engineer or architect that the nonresidential floodproofed structure shall meet the floodproofing criteria of section
3.03.008(b)(2);
(D) Description of the extent to which any watercourse or natural drainage
will be altered or relocated as a result of proposed development;
and
(E) Maintain a record of all such information in accordance with subsection
(b)(1) above.
(2) Approval or denial of a development permit by the floodplain administrator
shall be based on all of the provisions of this article and the following
relevant factors:
(A) The danger to life and property due to flooding or erosion damage.
(B) The susceptibility of the proposed facility and its contents to flood
damage and the effect of such damage on the individual owner.
(C) The danger that materials may be swept onto other lands to the injury
of others.
(D) The safety of access to the property in times of flood for ordinary
and emergency vehicles.
(E) The costs of providing governmental services during and after flood
conditions including maintenance and repair of streets and bridges,
and public utilities and facilities such as sewer, gas, electrical,
and water systems.
(F) The expected heights, velocity, duration, rate of rise and sediment,
transport of the floodwaters and the effects of wave action, if applicable,
expected at the site.
(G) The necessity to the facility of a waterfront location, where applicable.
(H) The availability of alternative locations, not subject to flooding
or erosion damage, for the proposed use.
(I) The availability of alternative locations, not subject to flooding
or erosion damage, for the proposed use.
(d) Variance procedures.
(1) The board of adjustment as established by the community shall hear
and render judgment on requests for variances from the requirements
of this article.
(2) The board of adjustment shall hear and render judgment on an appeal
only 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 article.
(3) Any person or persons aggrieved by the decision of the board of adjustment
may appeal such decision in the courts of competent jurisdiction.
(4) The floodplain administrator shall maintain a record of all actions
involving an appeal and shall report variances to the Federal Emergency
Management Agency upon request.
(5) Variances may be issued for the reconstruction, rehabilitation or
restoration of structures listed on the National Register of Historic
Places or the state inventory of historic places, without regard to
the procedures set forth in the remainder of this article.
(6) Variances may be issued for new construction and substantial improvements 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 the relevant factors in subsection
(c)(2) above have been fully considered. As the lot size increases beyond the one-half acre, the technical justification required for issuing the variance increases.
(7) Upon consideration of the factors noted above and the intent of this article, the board of adjustment may attach such conditions to the granting of variances as it deems necessary to further the purpose and objectives of section
3.03.002 of this article.
(8) Variances shall not be issued within any designated floodway if any
increase in flood levels during the base flood discharge would result.
(9) Variances may be issued for the repair or rehabilitation of historic
structures upon a determination that the proposed repair or rehabilitation
will not preclude the structure’s continued designation as a
historic structure and the variance is the minimum necessary to preserve
the historic character and design of the structure.
(10) Prerequisites for granting variances.
(A) Variances shall only be issued upon a determination that the variance
is the minimum necessary, considering the flood hazard, to afford
relief.
(B) Variances shall only be issued upon:
(i)
A showing of good and sufficient cause;
(ii)
A determination that failure to grant the variance would result
in exceptional hardship to the applicant; and
(iii)
A determination that the granting of a variance will not result
in increased flood heights, additional threats to public safety, extraordinary
public expense, create nuisances, cause fraud on or victimization
of the public, or conflict with existing local laws or ordinances.
(C) Any applicant to whom a variance is granted shall be given written
notice that the structure will be permitted to be built with a lowest
floor elevation below the base flood elevation, and that the cost
of flood insurance will be commensurate with the increased risk resulting
from the reduced lowest floor elevation.
(11) Variances may be issued by a community for new construction and substantial
improvements and for other development necessary for the conduct of
a functionally dependent use provided that:
(A) The criteria outlined in subsections (d)(1)–(9) of this section
are met; and
(B) The structure or other development is protected by methods that minimize
flood damages during the base flood and create no additional threats
to public safety.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08; Ordinance CO31-16-02-25-C1 adopted 2/25/16)
(a) General standards.
In all areas of special flood hazards
the following provisions are required for all new construction and
substantial improvements:
(1) All new construction and substantial improvements shall be designed
(or modified) and adequately anchored to prevent flotation, collapse,
or lateral movement of the structure resulting from hydrodynamic and
hydrostatic loads, including the effects of buoyancy.
(2) All new construction or substantial improvements shall be constructed
by methods and practices that minimize flood damage.
(3) All new construction or substantial improvements shall be constructed
with materials resistant to flood damage.
(4) All new construction and substantial improvements 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.
(5) All new and replacement water supply systems shall be designed to
minimize or eliminate infiltration of floodwaters into the system.
(6) New and replacement sanitary sewage systems shall be designed to
minimize or eliminate infiltration of floodwaters into the system
and discharges from the systems into floodwaters.
(7) On-site waste disposal systems shall be located to avoid impairment
to them or contamination from them during flooding.
(b) Specific standards.
In all areas of special flood hazards where base flood elevation data has been provided as set forth in sections
3.03.006(b),
3.03.007(b)(8), and
3.03.008(c)(4), the following provisions are required:
(1) Residential construction.
New construction or substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to one (1) foot above the base flood elevation. A registered professional engineer, architect or land surveyor shall submit a certification to the Floodplain Administrator that these standards as proposed in section
3.03.007(c)(1)(A), are satisfied.
(2) Nonresidential construction.
New construction and substantial
improvements of any commercial, industrial, or other nonresidential
structure shall either have the lowest floor, including basement,
elevated to one (1) foot above the base flood level or, together with
attendant utility and sanitary facilities, be designed so that below
the base flood level the structure is watertight with walls substantially
impermeable to the passage of water and with structural components
having the capability of resisting hydrostatic and hydrodynamic loads
and effects of buoyancy. A registered professional engineer or architect
shall develop and/or review structural design, specifications and
plans for the construction, and shall certify that the design and
method of construction are in accordance with accepted standards of
practice as outlined in this subsection. A record of such certification
which includes the specific elevation (in relation to mean sea level)
to which such structures are floodproofed shall be maintained by the
Floodplain Administrator.
(3) Enclosures.
New construction and substantial improvements,
with fully enclosed areas below the lowest floor that are usable solely
for parking of vehicles, building access or storage in an area other
than a basement 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 must either be certified by a registered professional
engineer or architect or meet or exceed the following minimum criteria:
(A) A minimum of two (2) openings on separate walls having a total net
area of not less than one (1) square inch for every square foot of
enclosed area subject to flooding shall be provided.
(B) The bottom of all openings shall be no higher than one (1) 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 exist of floodwaters.
(4) Manufactured homes.
(A) Require that all manufactured homes to be placed within zone A on
a community’s FHBM and FIRM shall be installed using methods
and practices which minimize flood damage. For the purposes of this
requirement, manufactured homes must be elevated and anchored to resist
flotation, collapse, or lateral movement. Methods of anchoring may
include, but are not limited to, use of over-the-top or frame ties
to ground anchors. This requirement is in addition to applicable state
and local anchoring requirements for resisting wind forces.
(B) Require that manufactured homes that are placed or substantially
improved within zones A1-30, AH and AE on the community’s FIRM
on sites:
(i)
Outside the manufactured home park or subdivision;
(ii)
In a new manufactured home park or subdivision;
(iii)
In an expansion to an existing manufactured home park or subdivision;
or
(iv)
In an existing manufactured home park or subdivision on which
a manufactured home has incurred substantial damage as a result of
flood, 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 anchored to an adequately anchored foundation
system to resist flotation, collapse, and lateral movement.
(C) Require that manufactured homes be placed or substantially improved
on sites in an existing manufactured home park or subdivision with
zones A1-30, AH, and AE on the community’s FIRM that are not
subject to the provisions of this subsection be elevated so that either:
(i)
The lowest floor of the manufactured home is at or above the
base flood elevation; or
(ii)
The manufactured home chassis is supported by the reinforced
piers or other foundation elements of at least equivalent strength
that are no less than thirty-six inches in height above grade and
be securely anchored to an adequately anchored foundation system to
resist flotation, collapse, and lateral movement.
(5) Recreational vehicles.
Require that recreational vehicles
placed on sites within zones A1-30, AH and AE on the community’s
FIRM either:
(A) Be on the site for fewer than 180 consecutive days and be fully licensed
and ready for highway use; or
(B) Meet the permit requirements of section
3.03.007(c)(1), and the elevation and anchoring requirements for manufactured homes in subsection
(4) of this section. 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.
(c) Standards for subdivision proposals.
(1) All subdivision proposals including the placement of manufactured home parks and subdivisions shall be consistent with sections
3.03.002,
3.03.003, and
3.03.004 of this article.
(2) All proposals for the development of subdivisions including the placement of manufactured home parks and subdivisions shall meet development permit requirements of sections
3.03.006(c),
3.03.007(c) and
3.03.008 of this article.
(3) Base flood elevation data shall be generated for subdivision proposals and other proposed development including the placement of manufactured home parks and subdivisions which are greater than fifty (50) lots or five (5) acres, whichever is lesser, if not otherwise provided pursuant to section
3.03.006(b) or
3.03.007(b)(8) of this article.
(4) All subdivision proposals including the placement of manufactured
home parks and subdivisions shall have adequate drainage provided
to reduce exposure to flood hazards.
(5) All subdivision proposals including the placement of manufactured
home parks and subdivisions shall have public utilities and facilities
such as sewer, gas, electrical and water systems located and constructed
to minimize or eliminate flood damage.
(d) Standards for areas of shallow flooding (AO/AH zones).
Located within the areas of special flood hazard established in section
3.03.006(b) are areas designated as shallow flooding. These areas have special flood hazards associated with base flood depths of one (1) to three (3) feet where a clearly defined channel does not exist and where the path of flooding is unpredictable and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow; therefore, the following provisions apply:
(1) All new construction and substantial improvements of residential
structures have the lowest floor (including basement) elevated above
the highest adjacent grade at least as high as the depth number specified
in feet on the community’s FIRM [at least three feet (3') if
no depth number is specified].
(2) All new construction and substantial improvements of nonresidential
structures:
(A) Have the lowest floor (including basement) elevated above the highest
adjacent grade at least as high as the depth number specified in feet
on the community’s FIRM [at least three feet (3') if no depth
number is specified]; or
(B) Together with attendant utility and sanitary facilities be designed
so that below the base flood level the structure is water-tight with
walls substantially impermeable to the passage of water and with structural
components having the capability of resisting hydrostatic and hydrodynamic
loads of effects of buoyancy.
(3) A registered professional engineer or architect shall submit a certification to the floodplain administrator that the standards of this article, as proposed in section
3.03.007(c)(1)(A), are satisfied.
(4) Require within zones AH and AO, adequate drainage paths around structures
on slopes, to guide floodwaters around and away from proposed structures.
(e) Floodways.
Floodways located within areas of special flood hazard established in section
3.03.006(b) are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and erosion potential, the following provisions shall apply:
(1) Encroachments are prohibited, including fill, new construction, substantial
improvements and other development within the adopted regulatory floodway
unless it has been demonstrated through hydrologic and hydraulic analyses
performed in accordance with standard engineering practice that the
proposed encroachment would not result in any increase in flood levels
within the community during the occurrence of the base flood discharge.
(2) If subsection
(e)(1) above is satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions of this subsection.
(3) Under the provisions of 44 CFR Chapter
1, Section 65.12, of the National Flood Insurance Regulations, a community may permit encroachment within the adopted regulatory floodway that would result in an increase in base flood elevations, provided that the community first applies for a conditional FIRM and floodway revision through FEMA.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08; Ordinance CO31-16-02-25-C1 adopted 2/25/16)
Any person who shall violate any provision of this article shall be deemed guilty of a misdemeanor and upon conviction, shall be fined in accordance with the general penalty provision found in section
1.01.009 of this code. Each day of violation shall constitute a separate offense.
(Ordinance CO59-08-09-25-C5 adopted 9/25/08)