Unless specifically defined below, words or phrases used in this chapter shall be interpreted to give them the meaning they have in common usage and cause the most reasonable application of the terms and requirements herein.
100-YEAR FLOOD. A flood having a recurrence interval that has a 1% chance of being equaled or exceeded during any given year (1% annual chance flood). The terms 100-YEAR FLOOD and "1% annual chance flood" are synonymous. The term does not imply that the flood will necessarily happen once every 100 years. Mandatory flood insurance requirements may apply.
500-YEAR FLOOD. A flood having a recurrence interval that has a 0.2% chance of being equaled or exceeded during any given year (0.2% annual chance flood). The term does not imply that the flood will necessarily happen once every 500 years and mandatory flood insurance requirement generally does not apply.
ACCESSORY STRUCTURE. A structure that is on the same parcel of property as a principal structure. Its use is incidental to the use of the principal structure; the ownership of the ACCESSORY STRUCTURE is the same owner as of the principal structure. An ACCESSORY STRUCTURE is a non-residential structure of low value that is used solely for the parking of vehicles and storage of tools, materials, or equipment. No human habitation is allowed within an ACCESSORY STRUCTURE.
ADDITION. Any improvement that expands the enclosed footprint or increases the square footage of an existing structure. This includes lateral ADDITIONS added to the side, front, or rear of a structure; vertical ADDITIONS added on top of a structure; and enclosures added underneath a structure.
ALLUVIAL FAN FLOODING. Flooding occurring on the surface of an alluvial fan or similar land form which originates at the apex and is characterized by high-velocity flows; active processes of erosion, sediment transport, and deposition; and unpredictable flow paths.
APPURTENANT STRUCTURE. See “accessory structure.”
APEX. A point on an alluvial fan or similar landform below which the flow path of the major stream that formed the fan becomes unpredictable and “alluvial fan flooding” can occur.
AREA OF FUTURE-CONDITIONS FLOOD HAZARD. The land area that would be inundated by the 1% annual chance (100-year) flood, based on future-conditions hydrology.
AREA OF SHALLOW FLOODING. A designated AO, AH, AR/AO or AR/AH Zone on a community's Flood Insurance Rate Map (FIRM) with a 1% chance or greater annual chance of flooding to an average depth of one to three feet where a clearly defined channel does not exist, where the path of flooding is unpredictable, and where velocity flow may be evident. Such flooding is characterized by ponding or sheet flow.
AREA OF SPECIAL FLOOD-RELATED EROSION HAZARD. The land within a community that is most likely to be subject to severe flood-related erosion losses. The area may be designated as Zone E on the Flood Hazard Boundary Map (FHBM). After the detailed evaluation of the special flood-related erosion hazard area, in preparation for publication of the FIRM, Zone E may be further refined.
AREA OF SPECIAL FLOOD HAZARD. The land in the floodplain within a community subject to a 1% or greater chance of flooding in any given year. The area may be designated as Zone A on the Flood Hazard Boundary Map (FHBM). After detailed rate making has been completed in preparation for publication of the FIRM, Zone A usually is refined into Zones A, AO, A1-30, AE, AI-99, AR, AR/A1-30, AR/AE, AR/AO, AR/AH, AR/A or Vi 30, VE, or V.
ASCE. The American Society of Civil Engineers.
BASE FLOOD. The flood having a 1% chance of being equaled or exceeded in any given year.
BASE FLOOD ELEVATION (BFE). The water surface elevation of the 1% annual chance flood event. It is the height in relation to mean sea level expected to be reached by the waters of the base flood at pertinent points in the floodplains of coastal and riverine areas. It is also the elevation shown on the FIRM and found in the accompanying Flood Insurance Study (FIS) for Zones A, AE, AH, A1-A30, AR, V1-V30, or VE that indicates the water surface elevation resulting from the flood that has a 1% chance of equaling or exceeding that level in any given year.
BASEMENT. Any area of the building having its floor subgrade (below ground level) on all sides.
BEST AVAILABLE DATA. The existing flood hazard information adopted by a community and reflected on an effective FIRM, FBFM, and/or within an FIS report; or draft or preliminary flood hazard information supplied by FEMA or from another source. Other sources may include, but are not limited to, the state, other federal agencies, or local studies, the more restrictive of which would be reasonably used by the community.
BREAKAWAY WALL. A wall that is not part of the structural support of the building and is intended through its design and construction to collapse under specific lateral loading forces, without causing damage to the elevated portion of the building or supporting foundation system. Any walls below the lowest floor in a building in a V or VE Zone should give way under wind and water loads without causing collapse, displacement, or other damage to the elevated portion of the building of the supporting pilings or columns. Breakaway walls apply only to V or VE Zones.
BUILDING. See “structure.”
CHANNELIZATION. The artificial creation, enlargement, realignment, or alteration of a stream channel's slope, shape, or alignment. Stream bank restoration may be deemed as CHANNELIZATION.
CODE OF FEDERAL REGULATIONS (CFR). The codification of the general and permanent rules published in the Federal Register by the executive departments and agencies of the federal government.
CONDITIONAL LETTER OF MAP REVISION (CLOMR). FEMA's comment on a proposed project that would, upon construction, affect the hydrologic and/or hydraulic characteristics of a flooding source and thus result in the modification of the existing regulatory floodway, the effective BFEs, and/or the SFHA. This letter does not revise an effective map; it indicates whether the project, if built as proposed, would be recognized by FEMA.
CONDITIONAL LETTER OF MAP REVISION BASED ON FILL (CLOMR-F). FEMA's comment on a proposed structure or property. The letter does not revise an effective map; it indicates whether the project, if built as proposed, would be removed from the floodplain.
CRAWLSPACE. An under-floor space that has its interior floor area (finished or not) no more than four feet from the bottom floor joist the next higher floor elevation, designed with proper openings that equalize hydrostatic pressures of flood water, and is not used for habitation.
CRITICAL FACILITY. A facility or building where even a slight chance of flooding is too great a threat. Typical critical facilities include hospitals, fire stations, police stations, schools, storage of critical records, assisted living and similar facilities.
CRITICAL FEATURE. An integral and readily identifiable part of a flood protection system, without which the flood protection provided by the entire system would be compromised.
DEED RESTRICTION. A clause in a deed that limits the future use of the property in some respect. Deed restrictions may impose a vast variety of limitations and conditions. For example, they may limit the density of buildings, dictate the types of structures that can be erected, or prevent buildings from being used for specific purposes or from being used at all.
DETACHED GARAGE. A building that is used solely for storage of materials or vehicle parking for up to four housing occupants. If a DETACHED GARAGE is designed or used for habitation or conducting business, or has multiple stories, then the building is not considered a DETACHED GARAGE under the NFIP.
DEVELOPMENT. Any human-made change in improved and unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation, or drilling operations, or temporary or permanent storage, equipment or materials.
ELEVATED BUILDING. A non-basement building:
(1) In the case of a building in Zone A1-30, AE, A, A99, AR, AO, AH, B, C, X and D, to have the top of the elevated floor above the ground level by means of pilings, columns (post and piers), or shear walls parallel to the flow of the water and adequately anchored so as not to impair the structural integrity of the building during a flood of up to the magnitude of the base flood.
(2) In the case of a building in Zone A1-30, AE, A, A99, AR, AO, AH, B, C, X and D, an ELEVATED BUILDING also includes a building elevated by means of fill or solid foundation perimeter walls with openings sufficient to facilitate the unimpeded movement of floodwaters.
ENCLOSURE. An enclosed walled-in area below the lowest floor of an elevated building. ENCLOSURES below the BFE may only be used for building access, vehicle parking, and storage.
EROSION. The process of the gradual wearing away of land masses by wind, water, or other natural agents.
EXISTING CONSTRUCTION. For the purposes of determining rates, structures for which the start of construction commenced before the effective date of the FIRM or before January 1, 1975, for FIRMs effective before that date. EXISTING CONSTRUCTION may also be referred to as “existing structures.”
EXISTING MANUFACTURED HOME PARK or SUBDIVISION. A manufactured home park or subdivision for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed before the effective date of the floodplain management regulations adopted by a community.
EXISTING STRUCTURES. See “existing construction.”
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.
FILL. The placement of materials, such as dirt, sand, or rock to elevate a structure, property, or portion of a property above the natural elevation of the site, regardless of where the material was obtained from. The common practice of removing unsuitable material and replacing with engineered material is not considered fill if the elevations are returned to the existing conditions. Any fill placed or used prior to the area being mapped as a flood hazard area is not deemed as fill.
FLOOD or FLOODING. Means:
(1) A general and temporary condition of partial or complete inundation of normally dry land areas from:
(a) The overflow of inland or tidal waters; or
(b) The unusual and rapid accumulation or runoff of surface waters from any source.
(2) Mudslides (i.e., mudflows) that are proximately caused by flooding as defined in this chapter and are akin to a river of liquid and flowing mud on the surfaces of normally dry land areas, as when earth is carried by a current of water and deposited along the path of the current.
(3) The collapse or subsidence of land along the shore of a lake or other body of water as a result of erosion or undermining caused by waves or currents of water exceeding anticipated cyclical levels or suddenly caused by an unusually high water level in a natural body of water, accompanied by a severe storm, or by an unanticipated force of nature, such as flash flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in flooding, as defined herein.
FLOOD INSURANCE RATE MAP (FIRM). An official map of a community, on which the Federal Emergency Management Agency has delineated both the areas of special flood hazard areas (SFHAs) and the risk premium zones applicable to the community.
FLOOD INSURANCE STUDY (FIS) or FLOOD ELEVATION STUDY. An examination, evaluation, and determination of flood hazards and, if appropriate, corresponding water surface elevations, or an examination, evaluation, and determination of mudslide (i.e., mudflow) and/or flood-related erosion hazards.
FLOODPLAIN DEVELOPMENT PERMIT. A community issued permit or document that is used for any development that occurs within an SFHA identified by FEMA or the community. It is used to address the proposed development to ensure compliance with the community's ordinance.
FLOOD OPENING. An opening in the wall of an enclosed structure that allows floodwaters to automatically enter and exit the enclosure. Refer to FEMA Technical Bulletin 1.
FLOOD PROTECTION SYSTEM. Physical structural works for which funds have been authorized, appropriated, and expended and which have been constructed specifically to modify flooding in order to reduce the extent of the areas within a community subject to a special flood hazard area (SFHZ) and to reduce the depths of associated flooding. Such a system typically includes hurricane tidal barriers, dams, reservoirs, levees, or dikes. These specialized flood-modifying works are constructed in conformance with sound engineering standards.
FLOODPLAIN or FLOOD-PRONE AREA. Any land area susceptible to being inundated by water from any source (see definition of “flooding”).
FLOODPLAIN MANAGEMENT. The operation of an overall program of corrective and preventive measures for reducing flood damage, including, but not limited to, emergency preparedness plans, flood control works, and floodplain management regulations.
FLOODPLAIN MANAGEMENT REGULATIONS. Zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as a floodplain ordinance, grading ordinance, and erosion-control ordinance) and other applications of police power. The term describes such state or local regulations, in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction.
FLOODPROOFING. Any combination of structural and non-structural 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. FLOODPROOFING can either be accomplished in the form of dry FLOODPROOFING in which the structure is watertight below the levels that need flood protection, or wet FLOODPROOFING in permanent or contingent measures applied to a structure that prevent or provide resistance to damage from flooding, while allowing floodwaters to enter the structure or area.
FLOODWAY. See “regulatory floodway.”
FLOODWAY ENCROACHMENT. The lines marking the limits of floodways on federal, state, and local floodplain maps.
FREEBOARD. A factor of safety usually expressed in feet above a flood level for 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, bridge openings, and the hydrological effect of urbanization of the watershed. The State of Utah adopted the most recent IBC and ASCE 24 standard "Flood Resistant Design and Construction" which established a FREEBOARD standard of one foot and the city thereby adopts.
FUNCTIONALLY-DEPENDENT USE. A use that cannot perform its intended purpose unless it is located or carried out in close proximity to water. The term includes only docking facilities, port facilities that are necessary for the loading and unloading of cargo or passengers, and ship building and ship repair facilities, but does not include long-term storage or related manufacturing facilities.
HIGHEST ADJACENT GRADE. The highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure. In AO Zones, the HIGHEST ADJACENT GRADE is utilized by comparing the lowest floor elevation to that of the HIGHEST ADJACENT GRADE and the depth of the AO Zone. Reference: Article V, Section D, “Standards for Areas of Shallow Flooding (AO/AH Zones).”
HISTORIC STRUCTURE. Any structure that is:
(1) Listed individually in the National Register of Historic Places (a listing maintained by the Department of the Interior) or preliminarily determined by the Secretary of the Interior as meeting the requirements for individual listing on the National Register;
(2) Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district;
(3) Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the Secretary of the Interior; or
(4) Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:
(a) By an approved state program as determined by the Secretary of the Interior; or
(b) Directly by the Secretary of the Interior in states without approved programs.
IBC. International Building Code, most recent edition.
LETTER OF MAP AMENDMENT (LOMA). An official amendment, by letter, to an effective FIRM. A LOMA establishes a property's location in relation to the SFHA. It is usually issued because a property or structure has been inadvertently mapped as being in the floodplain when the property or structure is actually on natural high ground above the BFE.
LETTER OF MAP REVISION (LOMR). FEMA's modification or revision to an entire or portion of the effective FIRM, or Flood Boundary and Floodway Map, or both. LOMRs are generally based on the implementation of physical measures that affect the hydrologic or hydraulic characteristics of a flooding source and thus result in the modification of the existing regulatory floodway, the effective BFEs, or the SFHA.
LETTER OF MAP REVISION BASED ON FILL (LOMR-F). FEMA's amendment, by letter, to an effective FIRM where fill was brought in or used to elevate a property, portion of property or structure above the BFE.
LEVEE. A-man-made structure, usually an earthen embankment, designed and constructed in accordance with sound engineering practices to contain, control, or divert the flow of water so as to provide protection from temporary flooding.
LEVEE SYSTEM. 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). The lowest natural elevation of the ground surface prior to construction next to the proposed walls of a structure. For an existing structure, it means the lowest point where the structure and ground touch, including but not limited to attached garages, decks, stairs, and basement windows.
LOWEST FLOOR. The lowest floor of the lowest enclosed area (including basement). An unfinished or flood-resistant enclosure, usable solely for the parking of vehicles, building access, or storage in an area other than a basement area, is not considered a building's LOWEST FLOOR; provided, that such enclosure is not built so as to render the structure in violation of the applicable non-elevation design requirement of § 60.3 of the National Flood Insurance Program regulations, being 44 C.F.R. § 60.3.
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 connected to the required utilities. MANUFACTURED HOME does not include a recreational vehicle; however, a MANUFACTURED HOME may be used for both residential and non-residential use.
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. The FHBM or the FIRM for a community issued by FEMA.
MEAN SEA LEVEL. For purposes of the National Flood Insurance Program (NFIP), the National Geodetic Vertical Datum (NGVD) of 1929, North American Vertical Datum of 1988 (NAVD 88), or other datum, to which base flood elevations shown on a community's Flood Insurance Rate Map (FIRM) are referenced.
NEW CONSTRUCTION. Structures for which the start of construction commenced on or after the effective date of a floodplain management regulation adopted by a community and includes any subsequent improvements to such structures. For the purposes of determining insurance rates, structures for the start of construction commenced on or after the effective date of an initial FIRM or after December 31, 1974, whichever is later, and includes any subsequent improvements to such structures.
NEW MANUFACTURED HOME PARK or SUBDIVISION. A MANUFACTURED HOME PARK or SUBDIVISION for which the construction of facilities for servicing the lots on which the manufactured homes are to be affixed (including, at a minimum, the installation of utilities, the construction of streets, and either final site grading or the pouring of concrete pads) is completed on or after the effective date of floodplain management regulations adopted by a community.
NO-RISE CERTIFICATIONS. Formal certifications signed and stamped by a professional engineer licensed to practice in the state, demonstrating through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that a proposed development will not result in any increase (zero feet) in flood levels within the community during the occurrence of a base flood event.
PHYSICAL MAP REVISION (PMR). FEMA's action whereby one or more map panels are physically revised and republished.
RECREATIONAL VEHICLE. A vehicle which is:
(1) Built on a single chassis;
(2) 400 square feet or less when measured at the largest horizontal projections;
(3) Designed to be self-propelled or permanently towable by a light-duty truck; and
(4) Designed primarily, not for use as a permanent dwelling, but as temporary living quarters for recreational, camping, travel, or seasonal use.
REGULATORY FLOODWAY. The channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height.
RIVERINE. Relating to, formed by, or resembling a river (including tributaries), stream, brook, creek, etc., which can be intermittent or perennial.
SECTION 1316. The section of the National Flood Insurance Act of 1968, as amended, which provides for the denial of flood insurance coverage for any property that the Administrator finds has been declared by a duly constituted state or local authority to be in violation of state or local floodplain management regulations. SECTION 1316 is issued for a property, not a property owner, and remains with the property even after a change of ownership.
SPECIAL FLOOD HAZARD AREA (SFHA). See “area of special flood hazard.”
START OF CONSTRUCTION. (For other than new construction or substantial improvements under the Coastal Barrier Resources Act, being 16 U.S.C. §§ 3501 et seq.) Includes substantial improvement and means the date the building permit was issued, provided the actual START OF CONSTRUCTION, repair, reconstruction, rehabilitation, addition, placement, or other improvement was within 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 slabs 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 basements, footings, piers, or foundations, or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual START OF CONSTRUCTION means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building.
STRUCTURE.
(1) For floodplain management purposes, a walled and roofed building, including a culvert, bridge, dam, or a gas or liquid storage tank, that is principally aboveground, as well as a manufactured home.
(2) For insurance purposes:
(a) A building with two or more outside rigid walls and a fully secured roof, which is affixed to a permanent site;
(b) A manufactured home ("a manufactured home," also known as a mobile home, is a structure built on a permanent chassis, transported to its site in one or more sections, and affixed to a permanent foundation); or
(c) A travel trailer without wheels built on a chassis and affixed to a permanent foundation, that is regulated under the community's floodplain management and building ordinances or laws.
(3) For insurance purposes, STRUCTURE does not mean a recreational vehicle or a park trailer or other similar vehicle, except as described in division (2)(c) above or a gas or liquid storage tank.
SUBSTANTIAL DAMAGE. Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damaged condition would equal or exceed 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 start of construction of the improvement. This includes structures that have incurred substantial damage, regardless of the actual repair work performed. The term does not, however, include either:
(1) Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local Code Enforcement Official and which are the minimum necessary to assure safe living conditions; or
(2) Any alteration of a historic structure provided that the alteration will not preclude the structure's continued designation as a historic structure.
VARIANCE. A grant of relief by the community from the requirements of a floodplain management regulation.
VIOLATION. The failure of a structure or other development to be fully compliant with the community's floodplain management regulations. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance required with the National Flood Insurance Program regulations in 44 C.F.R. § 60.3(b)(S), (c)(4), (c)(l0), (d)(3), (e)(2), (e)(4), or (e)(S) is presumed to be in VIOLATION until such time as that documentation is provided.
WATER SURFACE ELEVATION. The height, in relation to the North American Vertical Datum of 1988 (NAVD 88), of floods of various magnitudes and frequencies, such as the 1% annual chance flood event, in the floodplains of coastal or riverine areas.
WATERCOURSE. The channel and banks of an identifiable water in a creek, brook, stream, river, ditch, or other similar feature.
(Prior Code, § 13.20.020) (Ord. 16-2005, passed 11-16-2005; Ord. 22-2023, passed 11-1-2023)