Title 12 Flood Damage Prevention amd 2012.02.16Title 12
Teton County, Idaho Flood Damage Prevention Ordinance
I. STATUTORY AUTHORIZATION, FINDINGS OF FACT, PURPOSE, AND
OBJECTIVES 1
A. Statutory Authority 1
B. Findings of Fact 1
C. Statement of Purpose 2
D. Objectives 2
II. DEFINITIONS (Mandatory definitions are in bold face type) 2
III. GENERAL PROVISIONS 8
A. Lands to Which This Ordinance Applies 8
B. Basis for Area of Special Flood Hazard 8
C. Establishment of Floodplain Development Permit 8
D. Interpretation 8
E. Warning and Disclaimer of Liability 8
IV. ADMINISTRATION 9
A. Designation of Floodplain Ordinance Administrator 9
B. Permit Procedures 9
C. Duties and Responsibilities of the Administrator 10
V. PROVISIONS FOR FLOOD HAZARD REDUCTION 11
A. Subdivision Standards 11
B. Construction Standards 11
C. Manufactured Home Standards 13
D. Accessory Structures 13
E. Recreational Vehicle Standards 13
F. Hazardous Materials 14
G. Critical Facilities 14
H. Floodway Standards 14
I. Compensatory Storage 15
J. Standards for Zones with Base Flood Elevations . 15
K. Standards for Zones without Base Flood Elevations and/or Floodway
(A Zones) 16
L. Alteration of a Watercourse . 16
M. Requirement to Submit New Technical Data 17
VI. VARIANCE AND APPEAL PROCEDURES 17
A. Variance 17
B. Criteria for Variances 17
C. Variance Decision 18
D. Appeals 18
E. Decision 19
VII. PENALTIES FOR VIOLATION 19
VIII. SEVERABILITY 19
IX. REPEAL OF CONFLICTING PROVISIONS 19
X. EFFECTIVE DATE 20
Teton County Flood Damage Prevention Ordinance 2012.02.16
Teton County, Idaho Flood Damage Prevention Ordinance
AN ORDINANCE OF TETON COUNTY, IDAHO, A COUNTY OF THE STATE OF IDAHO,
ESTABLISHING PURPOSE AND AUTHORITY; PROVIDING DEFINITIONS; PROVIDING
APPLICABILITY; REQUIRING PERMITS; PROVIDING FOR ADMINISTRATION, PERMIT
PROCESSING AND THE AUTHORITY OF THE ADMINISTRATOR; PROVIDING
SUBDIVISION, CONSTRUCTION, MANUFACTURED HOME, RECREATIONAL VEHCILE,
AND FLOODWAY STANDARDS; PROVIDING VARIANCE AND APPEAL PROCESSES AND
CRITERIA; PROVIDING THAT A VIOLATION IS A MISDEMEANOR PUNISHABLE BY A
FINE NOT TO EXCEED ONE THOUSAND DOLLARS, OR JAIL NOT TO EXCEED ONE
HUNDERD EIGHTY DAYS, OR BOTH; PROVIDING SEVERABILITY; PROVIDING REPEAL
OF CONFLICTING ORDINANCES; AND PROVIDING AN EFFECTIVE DATE.
IT IS ORDAINED by the Board of County Commissioners of Teton County, Idaho as follows:
I. STATUTORY AUTHORIZATION, FINDINGS OF FACT,
PURPOSE, AND OBJECTIVES
A. Statutory Authority
The Legislature of the State of Idaho in I.C. 46-1020 through I.C. 46-1024, authorized local
government units to adopt a floodplain map and floodplain management ordinance that identifies
floodplains and that sets forth minimum development requirements in floodplains that are designed
to promote the public health, safety, and general welfare of its citizenry.
B. Findings of Fact
The flood hazard areas of Teton County, ID are subject to periodic inundation that may result in loss
of life and property, health and safety hazards, disruption of commerce and governmental services,
extraordinary public expenditures for flood relief and protection, and impairment of the tax base, all
of which adversely affect the public health, safety and general welfare.
(1) These flood losses are caused by structures in flood hazard areas, which are inadequately
elevated, flood-proofed, or otherwise unprotected from flood damages, and by the
cumulative effect of obstructions in floodplains causing increases in flood heights and
velocities.
(2) Local government units have the primary responsibility for planning, adoption and
enforcement of land use regulations to accomplish proper floodplain management as
enabled by Idaho State Statute in I.C. 46-1020 through I.C. 46-1024.
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C. Statement of Purpose
It is the purpose of this ordinance 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) Require that development that is vulnerable to floods, including structures and facilities
necessary for the general health, safety and welfare of citizens, be protected against flood
damage at the time of initial construction;
(2) Restrict or prohibit uses which are dangerous to health, safety and property due to water
or erosion hazards, or which increase flood heights, velocities, or erosion;
(3) Control filling, grading, dredging and other development which may increase flood
damage or erosion;
(4) Prevent or regulate the construction of flood barriers that will unnaturally divert flood
waters or that may increase flood hazards to other lands;
(5) Preserve and maintain natural floodplains, stream channels, and natural protective barriers
which carry and store flood waters;
(6) Prevent or minimize loss of hydraulic, geomorphic, and ecological functions of
floodplains and stream channels.
D. Objectives
The objectives of this ordinance are to:
(1) Protect human life, health and property from the dangers of flooding;
(2) Minimize damage to public facilities and utilities such as water purification and sewage
treatment plants, water and gas mains, electric, telephone and sewer lines, streets and
bridges located in floodplains;
(3) Help maintain a stable tax base by providing for the sound use and development of flood
prone areas;
(4) Minimize expenditure of public money for costly flood damage repair and flood control
projects;
(5) Minimize the need for rescue and emergency services associated with flooding and
generally undertaken at the expense of the general public;
(6) Minimize prolonged business interruptions.
II. DEFINITIONS (Mandatory definitions are in bold face type)
Unless specifically defined in Article II, words or phrases used in this ordinance shall be interpreted
according to the meaning they have in common usage.
“Accessory structure” means a structure on the same lot or parcel as a principal structure, the use of
which is incidental and subordinate to the principal structure. An insurable building should not be
classified as an accessory or appurtenant structure.
“Adversely affect/Adverse effect” means the effects that are a direct or indirect result of the proposed
action or its interrelated or interdependent actions and the effect is not discountable, insignificant or
beneficial. Discountable effects are extremely unlikely to occur. Insignificant effects relate to the size of
the impact and should never reach the scale where a take occurs. Based on best judgment, a person would
not: (1) be able to meaningfully measure, detect, or evaluate insignificant effects; or (2) expect
discountable effects to occur. Beneficial effects are contemporaneous positive effects without any adverse
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effects. In the event that the overall effect of the proposed action is beneficial, but is also likely to cause
some adverse effects, then the proposed action is considered to result in an adverse effect.
“Appeal” means a request for review of the Floodplain Administrator's interpretation of provisions
of this ordinance or request for a variance.
“Area of shallow flooding” means a designated AO or AH Zone on a community's Flood Insurance
Rate Map (FIRM) with base flood depths from one to three feet, and/or where a clearly defined
channel does not exist, where the path of flooding is unpredictable and indeterminate, and where
velocity flow may be evident.
“Area of special flood hazard” is the land in the floodplain within a County subject to a one percent
or greater chance of flooding in any given year. Zone designations on FIRMs include the letters A,
AE, V. Also known as the Special Flood Hazard Area (SFHA).
“Base Flood” means the flood having a one percent chance of being equaled or exceeded each year.
Also known as the “Regulatory Flood.”
“Base Flood Elevation (BFE)” means the water surface elevation during the base flood in relation to
a specified datum. The Base Flood Elevation (BFE) is depicted on the FIRM to the nearest foot and
in the FIS to the nearest .1 foot.
“Basement” means the portion of a structure including crawlspace with its floor sub grade (below
ground level) on all sides.
“Building” see “Structure.”
“Compensatory Storage” means an area outside the area of immediate development set aside for
floodwater storage lost as a result of the development.
“Critical Facility” means a facility that is critical for the health and welfare of the population and is
especially important following hazard events, such as hospitals, emergency management facilities
and public works facilities. Critical facilities include essential facilities, transportation systems,
lifeline utility systems, high potential loss facilities and hazardous material facilities.
“Datum” The vertical datum is a base measurement point (or set of points) from which all elevations
are determined. Historically, that common set of points has been the National Geodetic Vertical
Datum of 1929 (NGVD29). The vertical datum currently adopted by the federal government as a
basis for measuring heights is the North American Vertical Datum of 1988 (NAVD88).
“Development” means any manmade change to improved or unimproved real estate, including, but
not limited to, the construction of buildings, structures or accessory structures, or the construction of
additions or substantial improvements to buildings, structures or accessory structures; the placement
of mobile homes; mining, dredging, filling, grading, paving, excavation or drilling operations; the
deposition or extraction of materials, specifically including the construction of dikes, berms and
levees; or the removal of more than 35% canopy cover of the woody vegetation from within 50 feet
of the ordinary high water mark. The term "development" does not include the operation, cleaning,
maintenance or repair of any ditch, canal, lateral, drain, diversion structure or other irrigation or
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drainage works that is performed or authorized by the owner thereof pursuant to lawful rights and
obligations.
“Digital FIRM (DFIRM)” means Digital Flood Insurance Rate Map. It depicts flood risk and zones
and flood risk information The DFIRM presents the flood risk information in a format suitable for
electronic mapping applications.
“Existing Construction” means a structure for which the “start of construction” commenced before
03/31/2000.
“Existing manufactured home park or subdivision” means a manufactured home park or
subdivision where 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 final site grading or the pouring of concrete pads) is completed before 03/31/2000.
“Expansion to an existing manufactured home park or subdivision” 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.
“Federal Emergency Management Agency (FEMA)” is the agency with the overall responsibility
for administering the National Flood Insurance Program.
“Flood” or “flooding” means a general and temporary condition of partial or complete inundation of
normally dry land areas from:
(a) the overflow of inland waters; or
(b) the rapid accumulation or runoff of surface waters from any source.
“Flood Fringe” means the portion of the floodplain outside of the floodway covered by floodwaters
during the regulatory flood.
“Flood Insurance Rate Map (FIRM)” means an official map of a community, issued by the Federal
Insurance Administration, delineating the areas of special flood hazard and/or risk premium zones
applicable to the community.
“Flood Insurance Study (FIS)” means the official report by the Federal Insurance Administration
evaluating flood hazards and containing flood profiles, floodway boundaries and water surface
elevations of the base flood.
“Floodplain” means the land that has been or may be covered by floodwaters, or is surrounded by
floodwater and inaccessible, during the occurrence of the regulatory flood. The riverine floodplain
includes the floodway and the flood fringe. (I.C. 46-1021)
“Flood Proofing” 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.
“Flood Protection Elevation (FPE)” means an elevation that corresponds to the elevation of the one
percent (1%) chance annual flood (base flood), plus any increase in flood elevation due to floodway
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encroachment, plus 1 foot of freeboard. Therefore the Flood Protection Elevation for Teton
County is equal to BFE plus allowed floodway elevation plus one (1) foot freeboard (two feet
total above BFE).
“Floodway (Regulatory Floodway)” means the channel of a river or other watercourse and those
portions of the floodplain adjoining the channel required to discharge and store the floodwater or
flood flows associated with the regulatory flood.
“Freeboard” means a factor of safety usually expressed in feet above a flood level for the purposes
of floodplain management. Freeboard tends to compensate for the many unknown factors that could
contribute to flood heights greater than the height calculated for a selected size flood and floodway
conditions, such as wave action, obstructed bridge openings, debris and ice jams and the hydrologic
effects of urbanization in a watershed.
“Highest Adjacent Grade (HAG)” means the highest natural elevation of the ground surface prior
to construction, adjacent to the proposed walls of a structure. Refer to the Elevation Certificate,
FEMA Form 81-31, for HAG related to building elevation information.
“Historic Structure” means a structure that is:
(a) Listed individually in the National Register of Historic Places (a listing maintained by the
U.S. Department of Interior) or preliminarily determined by the Secretary of the Interior
as meeting the requirements for individual listing on the National Register.
(b) Certified or preliminarily determined by the Secretary of the Interior as contributing to
the historical significance of a registered historic district or to a district preliminarily
determined by the Secretary to qualify as a registered historic district.
(c) Individually listed on a state inventory of historic places and determined as eligible by
states with historic preservation programs which have been approved by the Secretary of
the Interior, or
(d) Individually listed on a local inventory of historic places and determined as eligible by
communities with historic preservation programs that have been certified either:
i. By an approved state program as determined by the Secretary of the Interior, or
ii. Directly by the Secretary of the Interior in states without approved programs.
“Letter of Map Change (LOMC)” means an official FEMA determination, by letter, to amend or
revise effective Flood Insurance Rate Maps, Flood Boundary and Floodway Maps, and Flood
Insurance Studies. LOMCs are issued in the following categories:
Letter of Map Amendment (LOMA)
A revision based on technical data showing that a property was incorrectly included in a
designated special flood hazard area. A LOMA amends the current effective Flood Insurance
Rate Map and establishes that a specific property is not located in a special flood hazard area.
Letter of Map Revision (LOMR)
A revision based on technical data that, usually due to manmade changes, shows
changes to flood zones, flood elevations, floodplain and floodway delineations, and
planimetric features. One common type of LOMR, a LOMR-F, is a determination that a
structure or parcel has been elevated by fill above the base flood elevation and is excluded
from the special flood hazard area.
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Conditional Letter of Map Revision (CLOMR)
A formal review and comment by FEMA as to whether a proposed project complies with the
minimum National Flood Insurance Program floodplain management criteria. A CLOMR
does NOT amend or revise effective Flood Insurance Rate Maps, Flood Boundary and
Floodway Maps, or Flood Insurance Studies.
“Levee” means a man-made structure, usually an earthen embankment, designed and constructed
according to sound engineering practices, to contain, control, or divert the flow of water so as to
provide protection from temporary flooding.
“Levee System” means a flood protection system that 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 Adjacent Grade (LAG)” means the lowest point of the ground level next to the structure.
Refer to the Elevation Certificate, FEMA Form 81-31, for LAG related to building elevation
information.
“Lowest Floor” means the lowest floor of the lowest enclosed area (including basement) used for
living purposes, which includes working, storage, cooking and eating, or recreation, or any
combination thereof. This includes any floor that could be converted to such a use including a
basement or crawl space. An unfinished or flood resistant enclosure, used solely for parking of
vehicles, building access, or storage, in an area other than a basement, is not considered a structure's
lowest floor. The lowest floor is a determinate for the flood insurance premium for a building, home
or business.
“Manufactured Home” means a structure, transportable in one or more sections, built on a
permanent chassis and designed to be used 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” means for purposes of the National Flood Insurance Program, the National
Geodetic Vertical Datum (NGVD) of 1929 or other datum, to which Base Flood Elevations shown on
a community’s FIRM are referenced.
“New construction” means a structure for which the “start of construction” commenced after
03/31/2000 and includes subsequent improvements to the structure.
“New Manufactured Home Park or Subdivision” means a place where 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 final site grading or the pouring
of concrete pads) is completed on or after 03/31/2000.
“Recreational Vehicle” means a vehicle that is:
(a) Built on a single chassis,
(b) 400 square feet or less when measured at the largest horizontal projection,
(c) Designed to be self-propelled or permanently towed by a light duty truck, and
(d) Designed primarily not for use as a permanent dwelling but as temporary living quarters
for recreational, camping, travel, or seasonal use.
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“Regulatory Floodway” means the channel of a river or other watercourse and the adjacent land
areas that must be reserved in order to discharge the base flood without cumulatively increasing the
water surface elevation more than a designated height.
“Repetitive Loss” means flood-related damages sustained by a structure on two separate
occasions during a 10-year period for which the cost of repairs at the time of each such flood event,
on the average, equals or exceeds 25 percent of the market value of the structure before the damages
occurred.
“Riparian” means of, adjacent to, or living on a surface water feature that receives hydrologic support
from that water feature and supports vegetation that is differentiated from the surrounding uplands areas.
“Riparian Habitat Zone” means the zone, or area, where riparian conditions exist.
“Special Flood Hazard Area (SFHA)” see “Area of special flood hazard”
“Start of construction” includes substantial improvement and means the date the development
permit was issued, provided the actual start of construction, repair, reconstruction, or improvement
was within 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 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 the alteration affects the external
dimensions of a building.
“Structure” means a walled and roofed building, including a gas or liquid storage tank that is
principally above ground. Structure shall include a manufactured home.
“Subdivision” for the purposes of Title 12 only means any subdivision of land resulting in a lot
of five acres or less or 50 lots, including a one-time-only lot split or other splits that may or may
not require subdivision review via Title 9.
“Substantial damage” 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 50 percent of its
market value before the damage occurred.
“Substantial improvement” means reconstruction, rehabilitation, addition, or other improvement of
a structure, the cost of which equals or exceeds 50 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 market value of the
structure should be (1) the appraised value of the structure prior to the start of the initial repair or
improvement, or (2) in the case of damage, the value of the structure prior to the damage occurring.
The term does not include either:
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(a) A project for improvement of a structure to correct existing violations of 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
(b) Alteration of a Historic Structure, provided that the alteration will not preclude the
structure's continued designation as an Historic Structure.
“Variance” is a grant of relief by the governing body from a requirement of this ordinance.
“Water surface elevation” means the height, in relation to the North American Vertical Datum
(NAVD) of 1988 (or other specified datum) of floods of various magnitudes and frequencies in the
flood plains of costal or riverine areas.
III. GENERAL PROVISIONS
A. Lands to Which This Ordinance Applies
This ordinance shall apply to all Special Flood Hazard Areas within the jurisdiction of Teton County,
Idaho. Nothing in this Ordinance is intended to allow uses or structures that are otherwise prohibited
by the zoning ordinance.
B. Basis for Area of Special Flood Hazard
The Special Flood Hazard Areas identified by the Federal Emergency Management Agency in its
Flood Insurance Study (FIS) for Teton County, Idaho and Incorporated Areas, dated August, 4, 1988,
with accompanying Flood Insurance Rate Maps (FIRM), and other supporting data, are adopted by
reference and declared a part of this ordinance. The FIS and the FIRM are on file at the office of the
Teton County Planning & Zoning Department, 150 Courthouse Drive, Driggs, ID 83422.
C. Establishment of Floodplain Development Permit
A Floodplain Development Permit shall be required prior to development activities in Special Flood
Hazard Areas established in Article III Section B.
D. Interpretation
In the interpretation and application of this ordinance 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.
E. Warning and Disclaimer of Liability
The degree of flood protection required by this ordinance is considered reasonable for regulatory
purposes and is based on scientific and engineering considerations. Larger floods can and will occur.
Flood heights may be increased by man-made or natural causes. This ordinance does not imply that
land outside the Special Flood Hazard Areas or uses permitted within such areas will be free from
flooding or flood damages. This ordinance shall not create liability on the part of Teton County,
Idaho or by any officer or employee thereof for flood damages that result from reliance on this
ordinance or an administrative decision lawfully made hereunder.
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IV. ADMINISTRATION
A. Designation of Floodplain Ordinance Administrator
The Planning Administrator, or his or her designee, is hereby appointed as the Floodplain
Administrator who is responsible for administering and implementing the provisions of this
ordinance.
B. Permit Procedures
Application for a Floodplain Development Permit shall be made to the Floodplain Administrator on
forms furnished by the administrator or the administrator’s designee prior to starting development
activities. Specifically, the following information is required:
(1) Application Stage
(a) Plans in duplicate drawn to scale with elevations of the project area and the nature,
location, dimensions of existing and proposed structures, earthen fill placement,
storage of materials or equipment and drainage facilities.
(b) Elevation in relation to the Flood Protection Elevation, or highest adjacent grade, of
the lowest floor level, including crawlspaces or basement, of all proposed structures;
(c) Elevations of the 10-, 50-, 100-, and 500- year floods, where the data are available
from FEMA or other existing sources;
(d) Boundaries of the Regulatory Floodplain, SFHA, and the floodway, where the data
are available from FEMA or other existing sources;
(e) Elevation to which any non-residential structure will be flood-proofed;
(f) Design certification from a registered, licensed professional engineer or registered,
licensed architect that any proposed non-residential flood-proofed structure will meet
the flood-proofing criteria in Article V(F)(2);
(g) Description of the extent to which any watercourse will be altered or relocated as a
result of a proposed development;
(h) If greater than 35% of the woody vegetation is to be removed within 50 feet from the
ordinary high water mark, a landscaping plan, prepared by a professional, must be
submitted that documents the minimization of impacts caused by the removal of the
vegetation. A professional engineer, certified floodplain manager or fluvial
morphologist shall demonstrate that the vegetation removal will not destabilize
stream banks or increase erosion potential on the floodplain.
(i) Documentation of additional permits required by Federal, State, or local law. The
application shall include written acknowledgment that the applicant understands that the
final certification of use or certificate of occupancy will be issued only if the applicant
provides copies of the required Federal, State, and local permits or letters stating that a
permit is not required. The floodplain permit shall remain invalid if those other permits
and approvals are not obtained prior to any ground disturbing work or structural
improvements.
(2) Construction Stage
(a) For all new construction and substantial improvements, the permit holder shall
provide to the Floodplain Administrator an as-built certification of the floor elevation
or flood-proofing level, using appropriate FEMA elevation or flood-proofing
certificate, immediately after the lowest floor or flood-proofing is completed. When
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flood-proofing is utilized for non-residential structures, the certification shall be
prepared by or under the direct supervision of a professional engineer or architect and
certified by same.
(b) Certificate deficiencies identified by the Floodplain Administrator shall be corrected
by the permit holder immediately and prior to work proceeding. Failure to submit
certification or failure to make the corrections shall be cause for the Floodplain
Administrator to issue a stop-work order for the project.
(3) Technical Review
(a) If the County does not have the expertise to evaluate the technical data that is part of
the application, the County may contract for an independent engineering review or
require a review by FEMA through the Letter of Map Revision process. The applicant
will pay the costs of an independent technical review.
(4) Expiration of Floodplain Development Permit
(a) All floodplain development permits shall be conditional upon the commencement of
work within 180 days. A floodplain development permit shall expire 180 days after
issuance unless the permitted activity has been substantially begun and thereafter is
pursued to completion.
C. Duties and Responsibilities of the Administrator
Duties of the Floodplain Administrator shall include, but shall not be limited to:
(1) Review all floodplain development permit applications to assure that the permit
requirements of this ordinance have been satisfied.
(2) Review proposed development to assure that necessary permits have been received from
governmental agencies from which approval is required by federal or state law, including
section 404 of the Federal Water Pollution Control Act Amendments of 1972, 33 U.S.C.
1334; the Endangered Species Act of 1973, 16 U.S.C. 1531-1544; and State of Idaho
Stream Channel Alteration permits, I.C. 42 Chapter 38 require that copies of such permits
be provided and maintained on file.
(3) When Base Flood Elevation data or floodway data are not available, then the Floodplain
Administrator shall require from the applicant, review and reasonably utilize any base
flood elevation and floodway data available from a federal, state or other source in order
to administer the provisions of this ordinance.
(4) When Base Flood Elevations or other current engineering data are not available, the
Floodplain Administrator shall take into account the flood hazards, to the extent they are
known, to determine whether a proposed building site will be reasonably safe from
flooding.
(5) Require and record the actual elevation in relation to the vertical datum on the
effective FIRM, or highest adjacent grade, of the lowest floor level, including basement,
of all new construction or substantially improved structures.
(6) Require and record the actual elevation in relation to the vertical datum on the
effective FIRM to which any new or substantially improved structures have been flood-
proofed.
(7) When flood-proofing is utilized for a structure, the Floodplain Administrator shall require
certification of design criteria from a registered professional engineer or architect.
(8) Where interpretation is needed of the exact location of boundaries of the Areas of Special
Flood Hazard including regulatory floodway (for example, where there appears to be a
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conflict between a mapped boundary and actual field conditions) the Floodplain
Administrator shall make the interpretation. Any person contesting the location of the
boundary shall be given a reasonable opportunity to appeal the interpretation as provided
in this Ordinance.
(9) Ensure that all development activities within the Regulatory Floodplain of the jurisdiction
of Teton County meet the requirements of this ordinance.
(10) Inspect all development projects to ensure compliance with all provisions of this
ordinance, including proper elevation of the structure.
(11) All records pertaining to the provisions of this ordinance shall be maintained in the
office of the Teton County Planning & Zoning Department and shall be open for public
inspection.
V. PROVISIONS FOR FLOOD HAZARD REDUCTION
A. Subdivision Standards
(1) All subdivision proposals shall be consistent with the need to minimize flood damage.
(2) All subdivision preliminary plats/development plans shall include the mapped flood
hazard zones from the effective FIRM.
(3) Base flood elevation data shall be generated and/or provided for subdivision proposals
and all other proposed development, including manufactured home parks and
subdivisions, greater than fifty lots or five acres, whichever is less.
(4) All subdivisions shall have at least one access road connected to land outside the
Regulatory Floodplain with the surface of the road at or above the FPE whenever
possible.
(5) All building envelopes shall be located a distance of at least twice the regular bankfull
channel width of the stream or river channel from the ordinary high water mark (or
bankfull location), or out of the SFHA boundary.
(6) All subdivisions shall have public utilities and facilities such as sewer, gas, electric and
water systems located and constructed to minimize flood damage.
(7) All subdivisions shall have adequate drainage provided to reduce exposure to flood
hazards.
(8) The final recorded subdivision plat shall include a notice that part of the property is in the
SFHA, as appropriate.
B. Construction Standards
In all Areas of Special Flood Hazard the following provisions are required.
(1) If a lot has a buildable site out of the Regulatory Floodplain, all new structures shall be
located in that area, when possible.
(2) If a lot does not have a buildable site out of the Regulatory Floodplain, all new structures,
pavement, and other development must be sited in the location that has the least impact
on floodplain function by locating the structures as far from the water body as possible or
placing the structures on the highest land on the lot.
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(3) New construction and substantial improvements of an existing structure, including a
structure that has been substantially damaged, shall be anchored to prevent flotation,
collapse or lateral movement of the structure.
(4) New construction and substantial improvements of an existing structure, including a
structure that has been substantially damaged, shall be constructed with materials and
utility equipment resistant to flood damage.
(5) New construction or substantial improvements of an existing structure, including a
structure that has been substantially damaged, shall be constructed by methods and
practices that minimize flood damage.
(6) All new construction or substantial improvements of an existing structure, including a
structure that has been substantially damaged, that includes a fully enclosed area located
below the lowest floor formed by the foundation and other exterior walls shall be
designed to be an unfinished or flood resistant enclosure. The enclosure shall be designed
to equalize hydrostatic flood forces on exterior walls by allowing for the automatic entry
and exit of floodwater. Designs for complying with this requirement must be certified by
a licensed professional engineer or architect or meet the following minimum criteria:
(a) Provide a minimum of two openings with a total net area of not less
i. than one square inch for every square foot of enclosed area subject to flooding;
ii. the bottom of all openings shall be no higher than one foot above the higher of
the exterior or interior grade or floor immediately below the opening;
iii. openings may be equipped with screens, louvers, valves or other coverings or
devices provided they permit the automatic flow of floodwater in both directions
without manual intervention.
(b) To comply with the “Lowest Floor” criteria of this ordinance, the unfinished or flood
resistant enclosure shall only be used for parking of vehicles, limited storage of
maintenance equipment used in connection with the premises, or entry to the elevated
area.
(c) The interior portion of such enclosed area shall not be partitioned or finished into
separate rooms.
(d) For crawlspace foundation types, construction must follow the guidelines in FEMA
TB 11-01, Crawlspace Construction for Structures Located in Special Flood Hazard
Areas: National Flood Insurance Program Interim Guidance, specifically:
i. Below grade crawlspaces are prohibited at sites where the velocity of floodwaters
exceed 5 feet per second;
et ii. Interior grade of the crawlspace below the BFE must not be more than 2 fe
below the lowest adjacent exterior grade (LAG);
iii. Height of the below grade crawlspace, measured from the lowest interior
grade of the crawlspace to the bottom of the floor joist must not exceed 4
feet at any point;
iv. Contain an adequate drainage system that removes floodwaters from the interior
area of the crawlspace.
(7) All heating and air conditioning equipment and components, all electrical, ventilation,
plumbing, and other facilities shall be designed and/or elevated to prevent water from
entering or accumulating within the components during flooding.
(8) New and replacement water supply systems shall be designed to minimize or to eliminate
infiltration of flood waters into the system.
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(9) New and replacement sanitary sewage systems shall be designed to minimize or to
eliminate infiltration of flood waters into the systems and discharges from the systems
into flood waters.
(10) On-site waste disposal systems shall be located outside of the floodway and constructed
to avoid functional impairment, or contamination from them, during flooding.
(11) Removal of greater than 35% of woody vegetative cover shall not decrease the stability
of the stream banks. A professional engineer, certified floodplain manager or fluvial
morphologist shall demonstrate that the vegetation removal will not destabilize stream
banks or increase erosion potential on the floodplain.
(12) Any alteration, repair, reconstruction or improvement to a structure that is not compliant
with the provisions of this ordinance, shall be undertaken only if the nonconformity is
minimal in order to meet health and safety standards.
C. Manufactured Home Standards
In all Areas of Special Flood Hazard where the Flood Protection Elevation is established, these
standards for manufactured homes and recreational vehicles that are an allowed use under the zoning
ordinance shall apply:
(1) Manufactured homes placed or substantially improved:
(a) On individual lots or parcels
(b) In new or substantially improved manufactured home parks or subdivisions
(c) In expansions to existing manufactured home parks or sub-divisions, or on a site in an
existing manufactured home park or subdivision where a manufactured home has
incurred “substantial damage” as the result of a flood, must have the lowest floor,
including basement, elevated to the Flood Protection Elevation.
(2) Manufactured homes placed or substantially improved in an existing manufactured home
park or subdivision may be elevated so that either:
(a) The lowest floor of the manufactured home is elevated to the Flood Protection
Elevation or one foot above the level of the base flood elevation, whichever is higher.
(b) The manufactured home chassis is elevated and supported by reinforced piers (or
other foundation elements of at least an equivalent strength) of no less that 36 inches
above the highest adjacent grade.
(3) Manufactured homes shall be anchored to prevent 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 standard shall be in addition to, and consistent with,
applicable state requirements.
(4) Manufactured homes placed on solid perimeter walls shall meet the flood vent
requirements in Article V(B)(4).
D. Accessory Structures
Relief from the elevation or dry flood-proofing standards may be granted for an accessory structure
containing no more than 200 square feet. Such a structure must meet the following standards:
(1) It shall not be used for human habitation;
(2) It shall be constructed of flood resistant materials;
(3) It shall be constructed and placed on the lot to offer the minimum resistance to the flow
of floodwaters;
(4) It shall be firmly anchored to prevent flotation;
(5) Services such as electrical and heating equipment shall be elevated or flood-proofed to or
above the Flood Protection Elevation;
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(6) It shall meet the opening requirements of Article V(B)(4).
E. Recreational Vehicle Standards
In all Areas of Special Flood Hazard, Recreational Vehicles, must either:
(1) Be on the site for fewer than 180 consecutive days;
(2) Be fully licensed and ready for highway use, on its wheels or jacking system, attached to
the site only by quick disconnect type utilities and security devices, and have no
permanently attached structures or addition, or
(3) The recreational vehicle must meet all the requirements for “New Construction,”
including the anchoring and elevation requirements.
F. Hazardous Materials
(1) No new development shall create a threat to public health, public safety, or water quality.
Chemicals, explosives, gasoline, propane, buoyant materials, animal wastes, fertilizers,
flammable liquids, pollutants, or other materials that are hazardous, toxic, or a threat to water
quality are prohibited from the Regulatory Floodplain. This prohibition does not apply to
small quantities of these materials kept for normal household use. This prohibition does not
apply to the continued operations of existing facilities and structures, reuse of existing
facilities and structures, or functionally dependent facilities or structures.
G. Critical Facilities
(1) Construction of new critical facilities shall be, to the extent possible, located outside the
limits of the Regulatory Floodplain.
(2) Construction of new critical facilities in the Regulatory Floodplain shall be permissible if no
feasible alternative site is available, provided
(a) Critical facilities shall have the lowest floor elevated three feet above the base flood
elevation or to the height of the 500-year flood, whichever is higher. If there is no
available data on the 500-year flood, the permit applicants shall develop the needed data
in accordance with FEMA mapping guidelines.
(b) Access to and from the critical facility shall be protected to the elevation of the 500-year
flood.
H. Floodway Standards
The following provisions shall apply in a floodway:
(1) A project in the regulatory floodway must undergo an encroachment review to determine
its effect on flood flows. An encroachment analysis must include:
(a) Determination and documentation that the filling, grading or construction of a
structure will not obstruct flood flows and will not cause an increase in flood heights
upstream or adjacent to the project site;
(b) Determination and documentation that grading, excavation, channel improvements,
bridge and culvert replacements that remove an obstruction, do not cause increases in
downstream flood flows;
(c) Certification and documentation by a licensed professional engineer that the project
will not result in a rise in flood heights;
(d) The Administrator may make the encroachment determination for minor projects,
such as projects that do not increase the natural grade (e.g., paving a driveway or
Teton County Flood Damage Prevention Ordinance 2012.02.16 Page 14 of 21
parking lot at existing grade, bank stabilization or revegetative measures, open fences
and small isolated obstructions such as a mailbox or telephone pole).
(2) Upon demonstrating that there are no alternatives, the applicant may propose an
encroachment in the floodway that will cause an increase in the base flood elevation in
excess of the allowable level provided that the applicant obtain a Conditional Letter of
Map Revision from FEMA before the development can be approved and permitted.
I. Compensatory Storage
New development shall not reduce the effective flood storage volume of the Regulatory Floodplain. A
development proposal shall provide compensatory storage if grading or other activity eliminates any
effective flood storage volume. Compensatory storage shall:
(1) Provide equivalent volume at equivalent elevations to that being displaced. For this purpose,
“equivalent elevation” means having similar relationship to ordinary high water and to the
best available 10-year, 50-year and 100-year water surface profiles;
(2) Be hydraulically connected to the source of flooding; and
(3) Provide compensatory storage in the same construction season as when the displacement of
flood storage volume occurs and before the flood season begins.
(4) The newly created storage area shall be graded and vegetated to allow fish access during
flood events without creating fish stranding sites.
J. Standards for Zones with Base Flood Elevations
In Special Flood Hazard Areas designated AE or A (with estimated BFE), the following provisions
are required.
(1) New residential construction and substantial improvements
(a) Where base flood elevation data are available, new construction or substantial
improvement of any residential structure or manufactured home shall have the lowest
floor, including basement, constructed at or above the County’s Flood Protection
Elevation. If solid foundation perimeter walls are used to elevate a structure, openings
sufficient to facilitate the unimpeded movement of flood waters shall be provided in
accordance with the construction standards in Article V(B)(4).
(2) Non-Residential Construction
(a) New construction or the substantial improvement of any non-residential structure
located in special flood hazard zones must be flood-proofed if the new construction
or improvement is not elevated. The structure and attendant utility and sanitary
facilities, must be designed to be water tight to the Flood Protection Elevation, with
walls substantially impermeable to the passage of water, and structural components
having the capability of resisting hydrostatic and hydrodynamic loads and the effect
of buoyancy. A licensed professional engineer or architect must certify that the
design and methods of construction are in accordance with accepted standards of
practice for meeting these provisions, and shall provide certification to the
Administrator.
(3) Where the floodway has not been determined, no new construction, substantial
improvements, or other development (including fill) shall be permitted in Zones A and
AE on the effective 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 County. Applicants of proposed projects that increase the
base flood elevation more than one foot are required to obtain and submit to the
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Floodplain Administrator, a FEMA-Approved Conditional Letter of Map Revision
(CLOMR) preconstruction.
(4) Post construction, the applicant must apply to FEMA for a Letter of Map Revision for
changes to the flood hazard map proposed in the CLOMR.
K. Standards for Zones Without Base Flood Elevations and/or
Floodway (A Zones)
These standards apply in Special Flood Hazard Areas where streams exist but no base flood elevation
data have been provided (A Zones), or where base flood data have been provided but a floodway has
not been delineated.
(1) When base flood elevation or floodway data have not been identified by FEMA in a
Flood Insurance Study and /or Flood Insurance Rate Maps, then the Floodplain
Administrator shall require, review, and reasonably utilize scientific or historic base
flood elevation and floodway data available from a federal, state, or other source, in
order to administer this ordinance. If data are not available from any source, only then
provisions 2 and 3 shall apply.
(a) Where the floodplain administrator has obtained base flood elevation data, applicants
of proposed projects that increase the base flood elevation more than one foot shall
obtain a Conditional Letter of Map Revision preconstruction and a Letter of Map
Revision post construction.
(2) No encroachments, including structures or fill, shall be located within an area equal
to the width of the stream or fifty feet, whichever is greater, measured from the
ordinary high water mark, unless certification by a licensed professional engineer
documents that the encroachment will not result in any increase in flood levels during
the base flood.
(3) Bioengineering or restoration projects may be authorized based upon reduced submittal
requirements, at the discretion of the Floodplain Administrator.
(4) In special flood hazard areas without base flood elevation data, new construction and
substantial improvements of existing structures shall have the lowest floor of the
lowest enclosed area (including basement or crawlspace) elevated no less than two feet
above the highest adjacent grade at the building site. Openings sufficient to facilitate the
unimpeded movement of flood waters shall be provided in accordance with the
construction standards in Articles V (B) and (C).
L. Alteration of a Watercourse
A water course is considered altered when any change occurs within its banks.
(1) The altered or relocated watercourse shall have a morphology that conveys the bankfull
discharge. Prior to issuance of a floodplain development permit, the applicant must
submit a description of the extent to which any water course will be altered or relocated
as a result of the proposed development and submit certification by a registered
professional engineer that the proposed channel morphology will convey the bankfull
discharge.
(2) Adjacent communities, the U.S. Army Corps of Engineers and the Idaho Department of
Water Resources Stream Channel Alteration program must be notified prior to any
alteration or relocation of a water source. Evidence of notification must be submitted to
the floodplain administrator and to the Federal Emergency Management Agency.
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(3) The applicant shall be responsible for providing the necessary maintenance for the altered
or relocated portion of the water course so that the flood carrying capacity will not be
diminished.
(4) The applicant shall meet the requirements to submit technical data in Sections K(1) and
K(2) when an alteration of a water course results in the relocation or elimination of the
special flood hazard area, including the placement of culverts.
(5) Bioengineering or restoration projects may be authorized based upon reduced submittal
requirements, at the discretion of the Floodplain Administrator.
M. Requirement to Submit New Technical Data
(1) For all development proposals that impact floodway delineations or base flood elevations,
the County shall ensure that technical data reflecting such changes be submitted to
FEMA within six months of the date such information becomes available. These
development proposals include:
(a) Floodway encroachments that increase or decrease base flood elevations or alter
floodway boundaries;
(b) Fill sites to be used for the placement of proposed structures where the applicant
desires to remove the site from the special flood hazard area in accordance with V
(A)(3);
(c) Alteration of watercourses that result in a relocation or elimination of the special
flood hazard area, including the placement of culverts;
(d) Subdivision or large-scale development proposals requiring establishment of base
flood elevations according to Article V (A)(3).
(2) It is the responsibility of the applicant to have technical data prepared in a format
required for a Conditional Letter of Map Revision or Letter of Map Revision and
submitted to FEMA. Submittal and processing fees for these map revisions shall be the
responsibility of the applicant.
VI. VARIANCE AND APPEAL PROCEDURES
A. Variance
(1) An application for a variance must be submitted to the Teton County Planning & Zoning
Department on the form provided by Teton County and include at a minimum the same
information required for a development permit and an explanation for the basis for the
variance request.
(2) Upon receipt of a completed application for a variance, the variance request will be set
for public hearing at the next Board of County Commissioners hearing in which time is
available for the matter to be heard.
(3) Prior to the public hearing, Notice of the hearing will be published in the official
newspaper of the Teton County at least 15 days prior to the hearing. In addition to the
newspaper publication, written notice shall be provided to all adjoining property owners.
(4) The burden to show that the variance is warranted and meets the criteria set out herein is
on the applicant
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B. Criteria for Variances
(1) Generally, the only condition under which a variance from the elevation standard may be
issued is for new construction and substantial improvements to be erected on a small or
irregularly shaped lot contiguous to and surrounded by lots with existing structures
constructed below the base flood level. As the lot size increases the technical justification
required for issuing the variance increases.
(2) Variances shall not be issued within a designated floodway if any increase in flood levels
during the base flood discharge would result.
(3) Variances shall only be issued upon a determination that the variance is the minimum
necessary, considering the flood hazard, to afford relief.
(4) Variances may be issued upon;
(a) A showing by the applicant of good and sufficient cause;
(b) A determination that failure to grant the variance would 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 and ordinances.
(5) Variances pertain to a physical piece of property; they are not personal in nature and do
not pertain to the structure, its inhabitants, economic or financial circumstances. They
primarily address small lots in densely populated residential neighborhoods.
(6) The granting of the specified variance will not be detrimental to the public welfare or
injurious to other property in the area in which the property is situated;
(7) Such variances will not violate the provisions of Idaho Code; and
(8) The requested variance is not a result of the actions of the applicant.
(9) The variance will not have the effect of nullifying the interest and purpose of Teton
County Code or the Comprehensive Plan.
C. Variance Decision
The decision to either grant or deny a variance shall be in writing and shall set forth the reasons for
such approval and denial. If the variance is granted, the property owner shall be put on notice along
with the written decision that the permitted building will have its lowest floor below the Flood
Protection Elevation and that (i) 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
$25 for $100 of insurance coverage and (ii) such construction below the base flood level
increases risks to life and property. Such notification shall be maintained with a record of all
variance actions
D. Appeals
The Board of County Commissioners shall hear and decide appeals from the interpretations of the
Administrator.
(1) An appeal must be filed with the Teton County Planning & Zoning Department within
fourteen (14) days of the date of any permit denial or interpretation of the Administrator.
Failure to timely file an appeal shall be considered a failure to exhaust the administrative
remedies. The appeal must set out the interpretation of the Administrator and a narrative
setting forth the facts relied upon by the appellant and the appellants claim regarding the
error in the interpretation.
(2) Upon receipt of a completed appeal, the appeal will be scheduled for the next available
Board of County Commissioners hearing to be heard. The Board of County
Commissioners shall consider the following in ruling on an appeal:
Teton County Flood Damage Prevention Ordinance 2012.02.16 Page 18 of 21
(a) All technical evaluations, all relevant factors, standards specified in other sections of
this ordinance, including:
i. The danger that materials may be swept onto other lands to the injury of others;
ii. The danger to life and property due to flooding or erosion damage;
iii. The susceptibility of the proposed facility and its contents to flood damage and
the effects of such damage on the individual landowner;
iv. The importance of the services provided by the proposed facility to the
County;
v. The necessity of the facility to a waterfront location, where applicable;
vi. The availability of alternative locations for the proposed use which are not
subject to flooding or erosion damage;
vii. The compatibility of the proposed use with existing and anticipated development;
viii. The relationship of the proposed use to the comprehensive plan and flood plain
management program for that area;
xi. The safety of access to the property in times of flooding for ordinary and
emergency vehicles;
x. The expected heights, velocity, duration, rate of rise, and sediment transport of
the flood waters and the effects of wave action, if applicable, expected at the site;
and
xi. The cost of providing government services during and after flood conditions,
including maintenance and repair of public utilities and facilities such as sewer,
gas, electrical, and water systems, and streets and bridges.
E. Decision
The Board of County Commissioners decision on appeal shall be in writing and set out the facts,
technical information and the legal basis for the decision.
VII. PENALTIES FOR VIOLATION
No structure or land shall hereafter be located, extended, converted or altered unless in full
compliance with the terms of this ordinance and other applicable regulations.
Violation of the provisions of this ordinance or failure to comply with any of its requirements,
including violation of conditions and safeguards established in connection with grants of variance or
special exceptions shall constitute a misdemeanor. Any person who violates this ordinance or fails to
comply with any of its requirements shall, upon conviction thereof, be fined not more than $1,000 or
imprisoned for not more than 180 days, or both. Each day the violation continues shall be considered
a separate offense. Nothing herein contained shall prevent Teton County, ID from taking such other
lawful actions as is necessary to prevent or remedy any violation.
VIII. SEVERABILITY
The ordinance is hereby declared to be severable. Should any portion of this ordinance be declared
invalid by a court of competent jurisdiction, the remaining provisions shall continue in full force and
effect and shall be read to carry out the purpose(s) of the ordinance before the declaration of partial
invalidity.
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IX. REPEAL OF CONFLICTING PROVISIONS
This ordinance shall not in any way impair or remove the necessity of compliance with any other
laws, ordinances, regulations, etc. Where this ordinance imposes a greater restriction, the provisions
of this ordinance shall control.
X. EFFECTIVE DATE
This ordinance shall be effective upon passage and publication as provided by law.
Approved by the Board of County Commissioners on the _____ day of _________________, 201__.
TETON COUNTY, IDAHO
Kathryn Rinaldi, Chair, Board of County Commissioners
ATTEST:
____________________________
Mary Lou Hansen, County Clerk