The town engineer or designee is hereby appointed the floodplain
administrator to administer and implement the provisions of this division
and other appropriate sections of 44 CFR (Emergency Management and
Assistance-National Flood Insurance Program regulations) pertaining
to floodplain management.
(Ordinance 2009-4-7E adopted 4/7/09)
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 division.
(2)
Review
permit application to determine whether to ensure that the proposed
building site project, 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 division.
(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 state water development board (TWDB) and also
the state commission on environmental quality (TCEQ), prior to any
alteration or relocation of a watercourse, and submit evidence of
such notification to the Federal Emergency Management Agency.
(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 3.12.037, 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 part III.
(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 more than one foot 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.
(11)
When a permit is sought for land which lies within an area of uncertain flood hazard or zone A, both as defined in section 3.12.035, require that the person seeking a permit supply sufficient appropriate information (as detailed in section 3.12.073) from which the floodplain administrator will be able to establish the base flood elevations and design flood elevation through the property. When such information has been provided, make a determination as to whether the land lies within or outside of an area of special flood hazard.
(12)
Determine if the proposed development could result in a significant
change to the watershed hydrology. If such a change appears possible,
require that the person seeking a permit supply sufficient appropriate
information to demonstrate the effect that the proposed development
would have on watershed hydrology. Also require appropriate measures
to mitigate such effects.
(13)
On an annual basis, review creek and watershed computer models and
floodplain mapping to determine whether the current watershed, creek
and floodplain conditions are adequately reflected in the models and
mapping.
(14)
Order regular inspection of all floodplains through the town to determine
whether nonpermitted or otherwise noncompliant developments or other
alterations have occurred. When such developments or alterations are
discovered, require that they be made compliant with the terms of
this division or that the creek or floodplain be restored to its prior
condition.
(Ordinance 2009-4-7E adopted 4/7/09)
(a)
Application
for a floodplain development permit (including fill) 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 location, dimensions, and elevation of proposed landscape
alterations, existing and proposed structures, including the placement
of manufactured homes, and the location of the foregoing in relation
to areas of special flood hazard. Additionally, the following information
is required:
(1)
Elevation (in relation to mean sea level), of the lowest floor (including
basement) of all new and substantially improved structures;
(2)
Elevation in relation to mean sea level to which any nonresidential
structure shall be floodproofed;
(3)
A certificate from a registered professional engineer or architect that the nonresidential floodproofed structure shall meet the floodproofing criteria of section 3.12.102(2);
(4)
Description of the extent to which any watercourse or natural drainage
will be altered or relocated as a result of proposed development;
(5)
Maintain a record of all such information in accordance with section 3.12.072(1);
(b)
Approval
or denial of a floodplain development permit by the floodplain administrator
shall be based on all of the provisions of this division and the following
relevant factors:
(1)
The danger to life and property due to flooding or erosion damage;
(2)
The susceptibility of the proposed facility and its contents to flood
damage and the effect of such damage on the individual owner;
(3)
The danger that materials may be swept onto other lands to the injury
of others;
(4)
The compatibility of the proposed use with existing and anticipated
development;
(5)
The safety of access to the property in times of flood for ordinary
and emergency vehicles;
(6)
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;
(7)
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;
(8)
The necessity to the facility of a waterfront location, where applicable;
(9)
The availability of alternative locations, not subject to flooding
or erosion damage, for the proposed use.
(Ordinance 2009-4-7E adopted 4/7/09)
(a)
If a fill permit is sought for land which lies within an area of uncertain flood hazard or zone A, both as defined in section 3.12.035, the person seeking a permit shall be required to provide sufficient information to the floodplain administrator from which base flood elevations and design flood elevations relative to the property may be established. Such information may include, but not be limited to, the items listed below, which are intended to set a standard for quality of work, but which will not relieve the applicant of the responsibility to comply with sound engineering and modeling procedures. Additionally, the person seeking a permit is responsible for all fees, data and information required by FEMA or other governing body having jurisdiction in the project area.
(1)
A current topographic map of the subject land at a scale of 1" =
200' or larger and a minimum contour interval of two feet. Elevation
contours shall be based on National Geodetic Vertical Datum (NGVD)
of 1929.
(2)
Hydraulic modeling (if required) shall include the following as applicable
to the current effective model, the modified effective model and the
proposed conditions model:
(A)
A mathematical hydraulic model of the creek and floodplain with cross-section
data based on data surveyed on the ground or the above-indicated topographic
map. The interval between cross-sections shall generally not exceed
300 feet (smaller intervals are, of course, acceptable, and, in any
case, sound engineering and modeling procedures shall be employed).
(B)
Roughness coefficients shall be field determined and shall generally
fall within the ranges specified in the town subdivision ordinance.
(C)
The model shall be generated for use with the computer program HEC-2,
as developed by the U.S. Army Corps of Engineers, Hydrologic Engineering
Center (use of other programs must first be approved by the floodplain
administrator).
(D)
The flows to be used in the model shall be obtained from the floodplain
administrator.
(E)
The model shall connect to and be compatible with other existing
hydraulic models within one-half mile upstream or one-half mile downstream
of the proposed development, if such models have been approved by
the floodplain administrator.
(F)
Where no approved hydraulic models exist upstream or downstream of
the proposed development, the model shall extend a minimum of one-half
mile upstream and one-half mile downstream of the proposed development.
(G)
Provide a detailed description of the method used for determining
the standing water surface elevation.
(H)
Provide a description of modeling techniques, and assumptions made,
and special or unusual conditions encountered.
(I)
Using the topographic map referred to in subsection (a)(1) of this section as a basis, delineate the base floodplain and design floodplain as determined through hydraulic modeling.
(J)
Provide a profile of the creek showing the creek bed and water surface
elevations for the base and design floods.
(K)
Provide plotted sections for effective, modified effective, and proposed
conditions hydraulic models.
(L)
Provide a diskette containing the model (ASCII format) to the floodplain
administrator.
(3)
Hydrologic modeling (if required).
(A)
Unless otherwise approved by the floodplain administrator, hydrologic
modeling of the proposed development shall be generated for use with
the computer program HEC-1, as developed by the U.S. Army Corps of
Engineers, Hydrologic Engineering Center. The current effective hydrologic
model of the watershed shall be obtained from the floodplain administrator.
(B)
Demonstrate that the unmodified current effective model may be used
on the applicant’s computer to duplicate the results on file
with the town.
(C)
Develop a model of the watershed with proposed development in place,
using the town’s current effective model as a platform.
(D)
Provide detailed calculations substantiating all modeling parameters
which would be affected by the proposed development.
(E)
Provide a description of modeling techniques, any assumptions made,
and special or unusual conditions encountered.
(F)
Provide a diskette containing the model (ASCII format) to the floodplain
administrator.
(4)
Certification by a registered professional engineer, attesting to
the methods used, modeling results and floodplain delineation accuracy.
(b)
A
fill permit shall be required for all development within areas of
special flood hazard within the town. Application for a fill permit
shall be presented to the floodplain administrator on permit forms
provided by the town or facsimiles thereof, which include drawings
(to scale) and technical information sufficient to fully support the
compliance of the proposed development with the provisions of this
division. These data shall include, but are not necessarily limited
to, information which demonstrates the effects of such development
on the floodplain, including impacts on the floodplains, flood elevations,
and velocities within the channel of the ten-year and 100-year mean
recurrence interval floods and in the discharges of the effective
FIS upstream of, downstream of, and along or through the proposed
development, and further, the person making application shall:
(1)
Show the lowest floor elevated to a minimum of three feet above the
base flood elevation or to two feet above the design flood elevation,
whichever is higher. In locations of assumed critical depth, the energy
gradient shall be used to establish these respective minimum lowest
floor elevations.
(2)
Furnish delineations of existing and post-development floodplains.
(3)
Demonstrate, with technical data, the impacts on the design flood
storage capacity of the floodplain. The town has adopted the policy
of restricting the loss of valley storage to 0% of the design floodplain.
(4)
Demonstrate, with technical data, that the flood-carrying capacity
within the altered or relocated portion of any watercourse is maintained.
(5)
Demonstrate with technical data that, at any point within the town,
the watershed or the creek, the effect of the proposed development:
(6)
Prepare technical data for the floodplain administrator’s review
and submittal to FEMA.
(7)
Affirm that all necessary permits have been obtained from those federal
(Corps of Engineers, section 404 of the Federal Water Pollution Control
Act (being 33 USC 1344), FEMA conditional and final approval, and
EPA NPDES permits), state, and other local governmental agencies from
which prior approval is required.
(c)
Approval
or denial of a fill permit by the floodplain administrator shall be
based on all of the provisions of this division and the following
relevant factors:
(1)
Adequacy and completeness of information and data accompanying the
permit application for the purpose of making an informed, qualified
determination;
(2)
The danger to life and property due to flooding or erosion damage;
(3)
The susceptibility of the proposed facility and its contents to flood
damage and the effect of such damage on the individual owner;
(4)
The danger that materials may float onto other lands to the injury
of others;
(5)
The compatibility of the proposed use with existing and anticipated
development;
(6)
The safety of access to the property in times of flood for ordinary
and emergency vehicles;
(7)
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;
(8)
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;
(9)
The necessity to the facility of a waterfront location, where applicable;
(10)
The availability of alternative locations, not subject to flooding
or erosion damage, for the proposed use;
(11)
The relationship of the proposed use to the comprehensive plan for
that area.
(Ordinance 2009-4-7E adopted 4/7/09)
(a)
The
appeal board, as established by the community, shall hear and render
judgment on requests for variances from the requirements of this division.
(b)
The
appeal board 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 division.
(c)
Any
person or persons aggrieved by the decision of the appeal board may
appeal such decision in the courts of competent jurisdiction.
(d)
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.
(e)
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 division.
(f)
Variances may be issued for new construction and substantial improvements to be erected on a lot of 1/2 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 section 3.12.073(b) have been fully considered. As the lot size increases beyond the 1/2 acre, the technical justification required for issuing the variance increases.
(g)
Upon consideration of the factors noted above and the intent of this division, the appeal board may attach such conditions to the granting of variances as it deems necessary to further the purpose and objectives of section 3.12.033.
(h)
Variances
shall not be issued within any designated floodway if any increase
in flood levels during the base flood discharge would result.
(i)
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.
(j)
Prerequisites
for granting variances:
(1)
Variances shall only be issued upon a determination that the variance
is the minimum necessary, considering the flood hazard, to afford
relief.
(2)
Variances shall only be issued upon:
(A)
Showing a good and sufficient cause;
(B)
A determination that failure to grant the variance would result in
exceptional hardship to the applicant; and
(C)
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.
(3)
Any application to which a variance is granted shall be given written
notice that the structure will be permitted to be built with the 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.
(k)
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:
(Ordinance 2009-4-7E adopted 4/7/09)
