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For the purpose of this chapter, the following definitions shall apply unless the context clearly indicates or requires a different meaning.
A ZONE. Portions of the SFHA in which the principal source of flooding is runoff from rainfall, snowmelt or a combination of both. In A ZONES, floodwaters may move slowly or rapidly, but waves are usually not a significant threat to buildings. These areas are labeled as Zone A, Zone AE, Zones A1-A30, Zone AO, Zone AH, Zone AR and Zone A99 on a FIRM or FHBM. The definitions are presented below.
(1) ZONE A. Areas subject to inundation by the 1% annual chance flood event. Because detailed hydraulic analyses have not been performed, no base flood elevation or depths are shown. Mandatory flood insurance purchase requirements apply.
(2) ZONE AE AND A1-A30. Areas subject to inundation by the 1% annual chance flood event determined by detailed methods. Base flood elevations are shown within these zones. Mandatory flood insurance purchase requirements apply. (Zone AE is on new and revised maps in place of Zones A1-A30.)
(3) ZONE AO. Areas subject to inundation by 1% annual chance shallow flooding (usually sheet flow on sloping terrain) where average depths are between one and three feet. Average flood depths derived from detailed hydraulic analyses are shown within this zone. Mandatory flood insurance purchase requirements apply.
(4) ZONE AH. Areas subject to inundation by 1% annual chance shallow flooding (usually areas of ponding) where average depths are between one and three feet. Average flood depths derived from detailed hydraulic analyses are shown within this zone. Mandatory flood insurance purchase requirements apply.
(5) ZONE AR. Areas that result from the decertification of a previously accredited flood protection system that is determined to be in the process of being restored to provide base flood protection. Mandatory flood insurance purchase requirements apply.
(6) ZONE A99. Areas subject to inundation by the 1% annual chance flood event, but which will ultimately be protected upon completion of an under construction federal flood protection system. These are areas of special flood hazard where enough progress has been made on the construction of a protection system, such as dikes, dams and levees, to consider it complete for insurance rating purposes. ZONE A99 may only be used when the flood protection system has reached specified statutory progress toward completion. No base flood elevations or depths are shown. Mandatory flood insurance purchase requirements apply.
ACCESSORY STRUCTURE (APPURTENANT STRUCTURE). A structure that is located on the same parcel of property as the principal structure and the use of which is incidental to the use of the principal structure. ACCESSORY STRUCTURES should constitute a minimal initial investment, may not be used for human habitation, and be designed to have minimal flood damage potential. Examples of ACCESSORY STRUCTURES are detached garages, carports, storage sheds, pole barns and hay sheds.
ADDITION (TO AN EXISTING STRUCTURE). Any walled and roofed expansion to the perimeter of a structure in which the addition is connected by a common load-bearing wall other than a firewall. Any walled and roofed addition, which is connected by a firewall or is separated by independent perimeter load-bearing walls, is new construction.
APPEAL. A request for a review of the Floodplain Administrator’s interpretation of any provision of this chapter or a request for a variance.
AREA OF SHALLOW FLOODING. A designated AO or AH Zone on the community’s flood insurance rate map (FIRM) with base flood depths from one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable and indeterminate, and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow.
BASE FLOOD ELEVATION (BFE). The elevation of the 1% annual chance flood.
BASEMENT. The portion of a structure having its floor sub-grade (below ground level) on all sides.
BUILDING. See STRUCTURE.
COMMUNITY. A political entity that has the authority to adopt and enforce floodplain ordinances for the area under its jurisdiction.
COMMUNITY RATING SYSTEM (CRS). A program developed by the Federal Insurance Administration to provide incentives for those communities in the regular program that have gone beyond the minimum floodplain management requirements to develop extra measures to provide protection from flooding.
CRITICAL FACILITY. A facility for which even a slight chance of flooding might be too great. CRITICAL FACILITIES include, but are not limited to, schools, nursing homes, hospitals, police, fire and emergency response installations, installations which produce, use or store hazardous materials or hazardous waste.
DEVELOPMENT. (1) Any human-made change to improved or unimproved real estate, including, but not limited to:
(a) Construction, reconstruction or placement of a structure or any addition to a structure;
(b) Installing a manufactured home on a site, preparing a site for a manufactured home or installing a recreational vehicle on a site for more than 180 days;
(c) Installing utilities, erection of walls and fences, construction of roads or similar projects;
(d) Construction of flood control structures such as levees, dikes, dams, channel improvements and the like;
(e) Mining, dredging, filling, grading, excavation or drilling operations;
(f) Construction and/or reconstruction of bridges or culverts;
(g) Storage of materials; or
(h) Any other activity that might change the direction, height or velocity of flood or surface waters.
(2) DEVELOPMENT does not include activities such as the maintenance of existing structures and facilities such as painting, re-roofing; resurfacing roads; or gardening, plowing and similar agricultural practices that do not involve filling, grading, excavation or the construction of permanent structures.
ELEVATED STRUCTURE. A non-basement structure built to have the lowest floor elevated above the ground level by means of fill, solid foundation perimeter walls, filled stem wall foundations (also called chain walls), pilings or columns (posts and piers).
ELEVATION CERTIFICATE. A certified statement that verifies a structure’s elevation information.
EMERGENCY PROGRAM. The first phase under which a community participates in the NFIP. It is intended to provide a first layer amount of insurance at subsidized rates on all insurable structures in that community before the effective date of the initial FIRM.
ENCROACHMENT. The advance or infringement of uses, fill, excavation, buildings, permanent structures or development into a floodplain, which may impede or alter the flow capacity of a floodplain.
EXISTING CONSTRUCTION. Any structure for which the “start of construction” commenced before the effective date of the community’s first floodplain ordinance.
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 community’s first floodplain ordinance.
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).
FEMA. The Federal Emergency Management Agency.
FIVE-HUNDRED YEAR FLOOD (500-YEAR FLOOD). The flood that has a 0.2% chance of being equaled or exceeded in any year.
FLOOD. A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow, the unusual and rapid accumulation, or the runoff of surface waters from any source.
FLOOD BOUNDARY AND FLOODWAY MAP (FBFM). An official map on which the Federal Emergency Management Agency (FEMA) or Federal Insurance Administration (FIA) has delineated the areas of flood hazards and regulatory floodway.
FLOOD HAZARD BOUNDARY MAP (FHBM). An official map of a community, issued by FEMA, where the boundaries of the areas of special flood hazard have been identified as Zone A.
FLOOD INSURANCE RATE MAP (FIRM). An official map of a community, on which FEMA has delineated both the areas of special flood hazard and the risk premium zones applicable to the community.
FLOOD INSURANCE STUDY (FIS). The official hydraulic and hydrologic report provided by FEMA. The report contains flood profiles, as well as the FIRM, FBFM (where applicable), and the water surface elevation of the base flood.
FLOOD PROTECTION GRADE (FPG). The elevation of the regulatory flood plus two feet at any given location in the SFHA. See FREEBOARD.
FLOODPLAIN. The channel proper and the areas adjoining any wetland, lake or watercourse which have been or hereafter may be covered by the regulatory flood. The FLOODPLAIN includes both the floodway and the fringe districts.
FLOODPLAIN MANAGEMENT. The operation of an overall program of corrective and preventive measures for reducing flood damage and preserving and enhancing, where possible, natural resources in the floodplain, including, but not limited to, emergency preparedness plans, flood control works, floodplain management regulations and open space plans.
FLOODPLAIN MANAGEMENT REGULATIONS. This chapter and other zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances and other applications of police power which control development in flood-prone areas. This term describes federal, state or local regulations in any combination thereof, which provide standards for preventing and reducing flood loss and damage. FLOODPLAIN MANAGEMENT REGULATIONS are also referred to as FLOODPLAIN REGULATIONS, FLOODPLAIN ORDINANCE, FLOOD DAMAGE PREVENTION ORDINANCE and FLOODPLAIN MANAGEMENT REQUIREMENTS.
FLOODPRONE AREA. Any land area acknowledged by a community as being susceptible to inundation by water from any source. See FLOOD.
FLOODPROOFING (DRY FLOODPROOFING). A method of protecting a structure that ensures that the structure, together with attendant utilities and sanitary facilities, is watertight to the floodproofed design elevation with walls that are substantially impermeable to the passage of water. All structural components of these walls are capable of resisting hydrostatic and hydrodynamic flood forces, including the effects of buoyancy, and anticipated debris impact forces.
FLOODPROOFING CERTIFICATE. A form used to certify compliance for non-residential structures as an alternative to elevating structures to or above the FPG. This certification must be by a registered professional engineer or architect.
FLOODWAY. The channel of a river or stream and those portions of the floodplains adjoining the channel which are reasonably required to efficiently carry and discharge the peak flood flow of the regulatory flood of any river or stream.
FREEBOARD. A factor of safety, usually expressed in feet above the BFE, which is applied for the purposes of floodplain management. It is used to compensate for the many unknown factors that could contribute to flood heights greater than those calculated for the base flood.
FRINGE. The portions of the floodplain lying outside the floodway.
FUNCTIONALLY DEPENDENT FACILITY. A facility which cannot be used for its intended purpose unless it is located or carried out in close proximity to water, such as a docking or port facility necessary for the loading and unloading of cargo or passengers, shipbuilding, ship repair or seafood processing facilities. The term does not include long-term storage, manufacture, sales or service facilities.
HARDSHIP (AS RELATED TO VARIANCES OF THIS CHAPTER). The exceptional hardship that would result from a failure to grant the requested variance. The Town Council requires that the variance is exceptional, unusual and peculiar to the property involved. Mere economic or financial HARDSHIP alone is not exceptional. Inconvenience, aesthetic considerations, physical handicaps, personal preferences or the disapproval of one’s neighbors likewise cannot, as a rule, qualify as an exceptional HARDSHIP. All of these problems can be resolved through other means without granting a variance, even if the alternative is more expensive, or requires the property owner to build elsewhere or put the parcel to a different use than originally intended.
HIGHEST ADJACENT GRADE. The highest natural elevation of the ground surface, prior to the start of construction, next to the proposed walls of a structure.
HISTORIC STRUCTURE. Any structure individually listed on the National Register of Historic Places or the State Register of Historic Sites and Structures.
INCREASED COST OF COMPLIANCE (ICC). The cost to repair a substantially damaged structure that exceeds the minimal repair cost and that is required to bring a substantially damaged structure into compliance with the local flood damage prevention ordinance. Acceptable mitigation measures are elevation, relocation, demolition or any combination thereof. All renewal and new business flood insurance policies with effective dates on or after June 1, 1997, will include ICC coverage.
LETTER OF MAP AMENDMENT (LOMA). An amendment to the currently effective FEMA map that establishes that a property is not located in a SFHA. A LOMA is only issued by FEMA.
LETTER OF MAP REVISION (LOMR). An official revision to the currently effective FEMA map. It is issued by FEMA and changes flood zones, delineations and elevations.
LETTER OF MAP REVISION BASED ON FILL (LOMR-F). An official revision by letter to an effective NFIP map. A LOMR-F provides FEMA’s determination concerning whether a structure or parcel has been elevated on fill above the BFE and excluded from the SFHA.
LOWEST ADJACENT GRADE. The lowest elevation, after completion of construction, of the ground, sidewalk, patio, deck support or basement entryway immediately next to the structure.
LOWEST FLOOR. The lowest of the following:
(1) The top of the lowest level of the structure;
(2) The top of the basement floor;
(3) The top of the garage floor, if the garage is the lowest level of the structure;
(4) The top of the first floor of a structure elevated on pilings or pillars; and
(5) The top of the floor level of any enclosure, other than a basement, below an elevated structure where the walls of the enclosure provide any resistance to the flow of flood waters unless:
(a) The walls are designed to automatically equalize the hydrostatic flood forces on the walls by allowing for the entry and exit of flood waters by providing a minimum of two openings (in addition to doorways and windows) in a minimum of two exterior walls having a total net area of one square inch for every one square foot of enclosed area. The bottom of all such openings shall be no higher than one foot above the exterior grade or the interior grade immediately beneath each opening, whichever is higher; and
(b) Such enclosed space shall be usable solely for the parking of vehicles and building access.
MANUFACTURED HOME. A structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term MANUFACTURED HOME does not include a “recreational vehicle.”
MANUFACTURED HOME PARK OR SUBDIVISION. A parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.
MAP AMENDMENT. A change to an effective NFIP map that results in the exclusion from the SFHA of an individual structure or a legally described parcel of land that has been inadvertently included in the SFHA (i.e., no alterations of topography have occurred since the date of the first NFIP map that showed the structure or parcel to be within the SFHA).
MAP PANEL NUMBER. The four-digit number followed by a letter suffix assigned by FEMA on a flood map. The first four digits represent the map panel, and the letter suffix represents the number of times the map panel has been revised. (The letter “A” is not used by FEMA, the letter “B” is the first revision.)
MARKET VALUE. The building value, excluding the land (as agreed to between a willing buyer and seller), as established by what the local real estate market will bear. MARKET VALUE can be established by independent certified appraisal, replacement cost depreciated by age of building (actual cash value), or adjusted assessed values.
MITIGATION. Sustained actions taken to reduce or eliminate long-term risk to people and property from hazards and their effects. The purpose of MITIGATION is twofold: to protect people and structures; and to minimize the cost of disaster response and recovery.
NATIONAL FLOOD INSURANCE PROGRAM (NFIP). The federal program that makes flood insurance available to owners of property in participating communities nationwide through the cooperative efforts of the federal government and the private insurance industry.
NATIONAL GEODETIC VERTICAL DATUM (NGVD) OF 1929 AS CORRECTED IN 1929. A vertical control used as a reference for establishing varying elevations within the floodplain.
NEW CONSTRUCTION. Any structure for which the “start of construction” commenced after the effective date of the community’s first floodplain ordinance.
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 the community’s first floodplain ordinance.
NORTH AMERICAN VERTICAL DATUM OF 1988 (NAVD 88) AS ADOPTED IN 1993. A vertical control datum used as a reference for establishing varying elevations within the floodplain.
OBSTRUCTION. Includes, but is not limited to, any dam, wall, wharf, embankment, levee, dike, pile, abutment, protection, excavation, canalization, bridge, conduit, culvert, building, wire, fence, rock, gravel, refuse, fill, structure, vegetation or other material in, along, across or projecting into any watercourse which may alter, impede, retard or change the direction and/or velocity of the flow of water; or due to its location, its propensity to snare or collect debris carried by the flow of water, or its likelihood of being carried downstream.
ONE-HUNDRED YEAR FLOOD (100-YEAR FLOOD). The flood that has a 1% chance of being equaled or exceeded in any given year. Any flood zone that begins with the letter A is subject to the 1% annual chance flood. See REGULATORY FLOOD.
ONE-PERCENT ANNUAL CHANCE FLOOD. The flood that has a 1% chance of being equaled or exceeded in any given year. Any flood zone that begins with the letter A is subject to the 1% annual chance flood. See REGULATORY FLOOD.
PARTICIPATING COMMUNITY. Any community that voluntarily elects to participate in the NFIP by adopting and enforcing floodplain management regulations that are consistent with the standards of the NFIP.
PHYSICAL MAP REVISION (PMR). An official republication of a community’s FEMA map to effect changes to base (1% annual chance) flood elevations, floodplain boundary delineations, regulatory floodways and planimetric features. These changes typically occur as a result of structural works or improvements, annexations resulting in additional flood hazard areas, or correction to base flood elevations or SFHAs.
POST-FIRM CONSTRUCTION. Construction or substantial improvement that started on or after the effective date of the initial FIRM of the community or after December 31, 1974, whichever is later.
PRE-FIRM CONSTRUCTION. Construction or substantial improvement, which started on or before December 31, 1974, or before the effective date of the initial FIRM of the community, whichever is later.
PROBATION. A means of formally notifying participating communities of violations and deficiencies in the administration and enforcement of the local floodplain management regulations.
PUBLIC SAFETY AND NUISANCE. Anything which is injurious to the safety or health of an entire community, neighborhood or any considerable number of persons, or unlawfully obstructs the free passage or use, in the customary manner, of any navigable lake, or river, bay, stream, canal or basin.
RECREATIONAL VEHICLE. A vehicle which is: built on a single chassis; 400 square feet or less when measured at the largest horizontal projections; designed to be self-propelled or permanently towable by a light duty truck; and designed primarily not for use as a permanent dwelling, but as quarters for recreational camping, travel or seasonal use.
REGULAR PROGRAM. The phase of the community’s participation in the NFIP where more comprehensive floodplain management requirements are imposed and higher amounts of insurance are available based upon risk zones and elevations determined in a FIS.
REGULATORY FLOOD. The flood having a 1% chance of being equaled or exceeded in any given year, as calculated by a method and procedure that is acceptable to and approved by the State Department of Natural Resources and the Federal Emergency Management Agency. The regulatory flood elevation at any location is as defined in § 154.03(B). The REGULATORY FLOOD is also known by the term BASE FLOOD, 1% ANNUAL CHANCE FLOOD and 100-YEAR FLOOD.
REPETITIVE LOSS. Flood-related damages sustained by a structure on two separate occasions during a ten-year period ending on the date of the event for which the second claim is made, in which the cost of repairing the flood damage, on the average, equaled or exceeded 25% of the market value of the structure at the time of each such flood event.
SECTION 1316. The section of the National Flood Insurance Act of 1968, being 42 U.S.C. 4001 et seq., as amended, which states that no new flood insurance coverage shall be provided for any property that the Administrator finds has been declared by a duly constituted state or local zoning authority or other authorized public body to be in violation of state or local laws, regulations or ordinances that intended to discourage or otherwise restrict land development or occupancy in flood-prone areas.
SPECIAL FLOOD HAZARD AREA (SFHA). Those lands within the jurisdictions of the town subject to inundation by the regulatory flood. The SFHAs of the town are generally identified as such on the county and incorporated areas flood insurance rate map prepared by the Federal Emergency Management Agency, dated February 6, 2013. The SFHAs of those parts of unincorporated county that are within the extraterritorial jurisdiction of the town or that may be annexed into the town are generally identified as such on the county and incorporated areas flood insurance rate map prepared by the Federal Emergency Management Agency and dated February 6, 2013. (These areas are shown on a FHBM or FIRM as Zone A, AE, A1-A30, AH, AR, A99 or AO.)
START OF CONSTRUCTION. Includes substantial improvement, and means the date the building 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 a 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, foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual START OF CONSTRUCTION means the first alteration of any wall, ceiling, floor or other structural part of a building, whether or not that alteration affects the external dimensions of the building.
STRUCTURE. A structure that is principally above ground and is enclosed by walls and a roof. The term includes a gas or liquid storage tank, a manufactured home or a prefabricated building. The term also includes recreational vehicles to be installed on a site for more than 180 days.
SUBSTANTIAL DAMAGE. Damage of any origin sustained by a structure whereby the cost of restoring the structure to it’s before damaged condition would equal or exceed 50% 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 50% of the market value of the structure before the “start of construction” of the improvement. This term includes structures that have incurred “repetitive loss” or “substantial damage” regardless of the actual repair work performed. The term does not include improvements of structures to correct existing violations of state or local health, sanitary or safety code requirements or any alteration of a “historic structure,” provided that the alteration will not preclude the structures continued designation as a “historic structure.”
SUSPENSION. The removal of a participating community from the NFIP because the community has not enacted and/or enforced the proper floodplain management regulations required for participation in the NFIP.
VARIANCE. A grant of relief from the requirements of this chapter, which permits construction in a manner otherwise prohibited by this chapter where specific enforcement would result in unnecessary hardship.
VIOLATION. The failure of a structure or other development to be fully compliant with this chapter. A structure or other development without the elevation, other certification, or other evidence of compliance required in this chapter is presumed to be in VIOLATION until such time as that documentation is provided.
WATERCOURSE. A lake, river, creek, stream, wash, channel or other topographic feature on or over which waters flow at least periodically. WATERCOURSE includes specifically designated areas in which substantial flood damage may occur.
WATER SURFACE ELEVATION. The height, in relation to the North American Vertical Datum of 1988 (NAVD 88) or National Geodetic Vertical Datum of 1929 (NGVD) (other datum where specified) of floods of various magnitudes and frequencies in the floodplains of riverine areas.
X ZONE. The area where the flood hazard is less than that in the SFHA. Shaded X ZONES shown on recent FIRMs (B zones on older FIRMs) designate areas subject to inundation by the flood with a 0.2% chance of being equaled or exceeded (the 500-year flood). Unshaded X ZONES (C ZONES on older FIRMs) designate areas where the annual exceedance probability of flooding is less than 0.2%.
ZONE. A geographical area shown on a FHBM or FIRM that reflects the severity or type of flooding in the area.
ZONE A. See definition for A ZONE.
ZONE B, C and X.
(1) Areas identified in the community as areas of moderate or minimal hazard from the principal source of flood in the area; however, buildings in these zones could be flooded by severe, concentrated rainfall coupled with inadequate local drainage systems.
(2) Flood insurance is available in participating communities but is not required by regulation in these zones. (ZONE X is used on new and revised maps in place of ZONES B and C.)
(Prior Code, § 92.02)