For purposes of these regulations certain terms are hereby defined as follows. Any word that is not defined herein shall be defined as in any recognized standard English dictionary. Additional definitions are also found in the Code of Federal Regulations for the National Flood Insurance Program in Title 44, § 59.1.
100-YEAR FLOOD. A flood having a 1% chance of being equaled or exceeded during any given year (1% annual chance flood). 100-YEAR FLOOD, 1% ANNUAL CHANCE FLOOD, and BASE FLOOD are synonymous. The term does not imply that the flood will happen once every 100 years. Mandatory flood insurance requirements may apply.
100-YEAR FLOODPLAIN. The area susceptible to being inundated by the base flood (1% annual chance flood).
500-YEAR FLOOD. A flood having 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 happen once every 500 years. Mandatory flood insurance requirements generally do not apply.
500-YEAR FLOODPLAIN. The area susceptible to being inundated by a 0.2% annual chance flood.
ACCESSORY STRUCTURE. A structure on the same parcel of property as the principal structure and with the same ownership. It is a structure of low value used solely for the parking of vehicles and storage of tools, materials, or equipment incidental to the use of the principal structure. 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 including lateral additions to the sides, front, or rear of a structure, vertical additions on top of a structure, and enclosures or crawlspaces made underneath a structure.
APPROXIMATE STUDIES. Flood hazard mapping using approximate study methods that show the approximate outline of the base floodplain. An APPROXIMATE STUDY does not produce a base flood elevation.
AREA OF SHALLOW FLOODING. A designated AO, AH, or VO zone on the flood insurance rate map (FIRM) characterized by ponding (AH zone) or sheet flow (AO zone) and having 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.
AUTHORIZED AGENT. A person who has been legally empowered to act on behalf of another person or an entity. Only a licensed attorney may act as agent for an incorporated municipality.
BASE FLOOD. The flood having a 1% chance of being equaled or exceeded in any given year (1% annual chance flood). BASE FLOOD is also referred to as the 100-YEAR FLOOD.
BASE FLOOD ELEVATION (BFE). The surface elevation of the 1% annual chance flood event, relative to a standard datum. The county’s flood insurance rate map (FIRM) uses the North American Vertical Datum (NAVD 88).
BASEMENT. Any area of a building having its floor sub-grade (below ground level) on all sides. A walkout basement that does not require a step up to the grade is not considered a BASEMENT.
BENCHMARK. A monument on the ground which shows the elevation of that monument above sea level within a standard datum or design plan.
BEST AVAILABLE DATA. Existing flood hazard information adopted by a community and reflected on the effective FIRM and FIS report; or draft of preliminary flood hazard information supplied by FEMA or from another source. Other sources may include, but are not limited to, state, other federal agencies, or local studies, the more restrictive of which would be reasonably used by the community.
BUFFER ZONE. See FLOOD HAZARD AREA BUFFER ZONE.
BUILDING. See STRUCTURE.
CHANNELIZATION. The artificial creation, enlargement, realignment, or alteration of a stream channel’s slope, shape, or alignment. Streambank 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. The letter does not revise an effective map; it indicates whether the project, if built as proposed, would be recognized by FEMA. A CLOMR is followed by a LOMR upon completion of the project.
CONDITIONAL LETTER OF MAP REVISION BASED ON FILL (CLOMR-F). FEMA’s comment on a proposed structure or property. The letter from FEMA 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 of the next higher floor elevation, designed with proper flood openings to equalize hydrostatic pressures of floodwater, and is not used for habitation. (Refer to FEMA Technical Bulletin No. 1: Crawlspaces.)
DATUM. A common vertical elevation reference usually in relation to sea level such as the National Geodetic Vertical Datum (NGVD 29), North American Vertical Datum (NAVD 88), or other datum.
DEED RESTRICTION. A clause in a deed that limits the future use of the property in some respect. DEED RESTRICTIONS may impose a 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 or parts of 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.
DETAILED STUDIES. Flood hazard mapping studies that are done using hydrologic and hydraulic methods that produce base flood elevations, floodways, and other pertinent flood data.
DEVELOPMENT. Any human-made change to improved or unimproved real estate, including, but not limited to, buildings or other structures, temporary or permanent storage of materials, mining, dredging, filling, grading, paving, excavations, or drilling.
ELEVATED BUILDING. A non-basement building to have the top of the elevated floor elevated above the ground level by means of pilings, columns, fill, solid foundation, or perimeter walls forming an enclosure.
EROSION. The process of the gradual wearing away of land masses by wind, water, or other natural agents.
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. Any buildings and structures for which the start of construction commenced before October 1, 1986, the effective date of the county’s FIRM. EXISTING STRUCTURES may also be referred to as 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).
FACILITY. Any human-made or human-placed item other than a structure.
FEMA. The Federal Emergency Management Agency.
FILL.
(1) 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.
(2) The common practice of removing unsuitable material and replacing with engineered material is not considered FILL if the elevations are returned to existing conditions.
(3) Any FILL placed or used prior to the area being mapped as a flood hazard area is not deemed as FILL.
FLOOD or FLOODING. A general and temporary condition of partial or complete inundation of normally dry land from the overflow of inland or tidal waters or the unusual and rapid accumulation or run-off of surface waters from any source.
FLOOD FRINGE. That portion of the floodplain outside of the floodway (often referred to as FLOODWAY FRINGE).
FLOOD HAZARD AREA. The area subject to a 1% or greater chance of flooding in any given year. Where a discrepancy between best available data and the flood insurance rate map conflict, the greater of the two areas shall be used.
FLOOD HAZARD AREA BUFFER ZONE. An area regulated by the community which is outside of, and adjacent to, a flood hazard area where residual flood hazards may exist and where typical damage from sub-surface flood conditions and by flooding events that exceed the base flood elevation are anticipated and reasonably preventable by compliance with specific design requirements.
FLOOD INSURANCE. The insurance coverage provided under the National Flood Insurance Program. FLOOD INSURANCE coverage is available for all properties in the county.
FLOOD INSURANCE RATE MAP (FIRM). An official map of a community, on which the Federal Emergency Management Agency has delineated both the areas of special flood hazards and the risk premium zones applicable to the community. A FIRM that has been made available digitally is called a DIGITAL FLOOD INSURANCE RATE MAP (DFIRM).
FLOOD INSURANCE STUDY (FIS). The official report provided by the Federal Emergency Management Agency (FEMA). The report contains community and study details, flood profiles, and water surface elevation of the base flood associated with the flood rate insurance map.
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, mitigation plans and projects, and floodplain management regulations.
FLOODPLAIN MANAGEMENT REGULATIONS. Zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as a flood damage protection, drainage, nuisance and erosion control ordinances), and other applications of police power in any combination thereof, which provide standards for the purpose of flood damage prevention and reduction.
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 No. 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 and the extent of the depths of associated flooding.
(1) Such a SYSTEM typically includes dams, reservoirs, levees, or dikes. These specialized, flood-modifying works are those constructed in conformance with sound engineering standards.
(2) FEMA only accredits levees, both private and public, that have been certified by a professional engineer or firm in which the certification shows that the levees have met and continues to meet the minimum regulatory standards cited in Title 44, Chapter 1, § 65.10 of the Code of Federal Regulations (44 C.F.R. 65.10).
FLOOD RESISTANT MATERIALS. Any construction material capable of withstanding direct and prolonged contact with floodwaters without sustaining any damage that requires more than low-cost repair (such as painting).
FLOOD ELEVATION STUDY. An examination, evaluation, and determination of flood hazards and, if appropriate, corresponding water surface elevations.
FLOODPLAIN or FLOOD-PRONE AREA. Any land area susceptible to being inundated by water from any source, whether or not identified by FEMA. (See definition of FLOOD or FLOODING.)
FLOODPLAIN DEVELOPMENT PERMIT. The community-issued authorization for development to occur within an SFHA identified by FEMA or a flood hazard area identified by the community. The DEVELOPMENT PERMIT, together with documentation provided during the application review process verifies compliance with the community’s ordinance.
FLOODPLAIN DEVELOPMENT PERMIT APPLICATION. The community document used to compile applicant, agent, site, and development details for any project or development proposed within an SFHA identified by FEMA or a flood hazard area identified by the community. The application for permit initiates review of the proposed development, outlines general requirements, terms, and conditions of a permit and endorses applicant consent to ensure compliance with this chapter.
FLOODPLAIN OR FLOOD-PRONE AREA. Any land area susceptible to being inundated by water from any source (see definition of flooding).
FLOODPROOFING.
(1) Any combination of structural and non-structural additions, changes, or adjustments to structures that reduce or eliminate flood damage to real estate or improved real property, water and sanitary facilities, structures, and their contents.
(2) 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 REUGLATORY FLOODWAY.
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 or expected, such as bridge or culvert openings, and the hydrological effect of urbanization of the watershed, and increases of flood frequency and duration.
FUTURE-CONDITIONS FLOOD HAZARD AREA. The land area that would be inundated by the 1% annual chance (100-year) flood based on future-conditions hydrology.
FUTURE-CONDITIONS HYDROLOGY. The flood discharges associated with projected land-use conditions based on a community’s zoning maps and/or comprehensive land-use plans and without consideration of projected future construction of flood detention structures or projected future hydraulic modifications within a stream or other waterway, such as bridge and culvert construction, detention, fill, and excavation.
HIGHEST ADJACENT GRADE. The highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.
HISTORIC STRUCTURE. Any structure that is:
(1) Listed individually in the National Register of Historic Places (a listing maintained by the Department of 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 of the Interior to qualify as a registered historic district;
(3) Individually listed on the State Inventory of Historic Places in states with historic preservation programs which have been approved by the Secretary of Interior; or
(4) Individually listed on the Local Inventory of Historic Places in communities with historic preservation programs that have been certified:
(a) By an approved state program, as determined by the Secretary of the Interior, or
(b) By the Secretary of the Interior in states without approved programs.
LETTER OF MAP AMENDMENT (LOMA). An official amendment to an effective FIRM by letter from FEMA. 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).
(1) FEMA’s modification or revision to the effective FIRM.
(2) 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). An official amendment to an effective FIRM by letter from FEMA 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 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 parking of vehicles, building access, or storage in an area other than a basement area, is not considered a building’s LOWEST FLOOR.
MANUFACTURED HOME. A structure that is transportable in one or more sections, built on a permanent chassis, 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; 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.
MEAN SEA LEVEL. For purposes of this chapter, the North American Vertical Datum (NAVD 88), to which base flood elevations shown on the county’s flood insurance rate map are referenced.
NAVD. North American Vertical Datum of 1988.
NEW CONSTRUCTION. Structures for which the “start of construction” commenced on or after the effective date of the county’s floodplain management regulations, adopted February 28, 1989, and includes any subsequent improvements to such structures. For the purposes of determining insurance rates, structures for which the “start of construction” commenced on, or after, the October 1, 1986, the effective date of the county’s initial FIRM, 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.
NGVD. National Geodetic Vertical Datum of 1929.
NO-RISE CERTIFICATION. A formal certification 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 practices that a proposed development will not result in any increase (0.00 feet) in flood levels within the community during the occurrence of a base flood event.
RECREATIONAL VEHICLE. A vehicle that is built on a single chassis, 400 square feet or less when measured at the largest horizontal projection, 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 temporary living quarters for recreational, camping, travel, or seasonal use. A RECREATIONAL VEHICLE is ready for highway use if it is fully licensed on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions.
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. The county’s FIS uses the minimum federal standard limitation of one foot, with provision that hazardous velocities are not produced.
RESIDUAL FLOOD HAZARD. Risks associated with subsurface flood conditions and flooding from events that exceed the base flood in areas near to flood hazard areas.
RIVERINE. Relating to, formed by, or resembling a river (including tributaries), stream, brook, creek, and the like, 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 Floodplain 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.
SHALLOW FLOODING. Flooding characterized by ponding or sheet flow where a clearly defined channel does not exist, where the path of flooding is unpredictable and where velocity flow may be evident. The flood insurance rate map (FIRM) designates areas of shallow flooding as zone AO or AH.
SPECIAL FLOOD HAZARD AREA (SFHA). The land in the floodplain subject to a 1% or greater chance of flooding in any given year designated as Zone A or AE on the county’s flood insurance rate map.
START OF CONSTRUCTION. The date the building permit was issued, provided the actual start of construction, repair, reconstruction, rehabilitation, addition, placement, or other improvement is within 180 days of the permit. The actual START OF CONSTRUCTION means the first placement of permanent construction of a structure on a site, such as the pouring of a slab or footings, any work beyond the stage of excavation, or the placement of a manufactured home on a foundation. 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. Any walled and roofed building or manufactured home, culvert, bridge, or dam, or a gas or liquid storage tank which is principally above ground, as well as a manufactured home.
SUBSTANTIAL DAMAGE. Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed 50% of the market value of the structure before the damage occurred. This term also applies to structures which have incurred any damage that equals or exceeds 50% of the structure’s market value, regardless of the actual repair work performed. SUBSTANTIAL DAMAGE also means flood-related damage sustained by a structure on two separate occasions during a ten-year period for which the cost of repairs at the time of each such flood event, on average, equals or exceeds 25% of the market value of the structure before the damage occurred.
SUBSTANTIAL IMPROVEMENT. Any repair, reconstruction, rehabilitation, addition, or improvement of a building or 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 which have incurred “substantial damage,” regardless of the actual repair work performed. The term does not, however, include either:
(1) Any project for improvement of a structure to correct existing of state or local health, sanitary, or safety code violations identified by the building official and that are the minimum necessary conditions 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 from the requirements of this chapter which permits construction in a manner otherwise prohibited by this chapter where strict enforcement would result in unnecessary hardship.
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 of 44 C.F.R. 60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or (e)(5) 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 (NAVD) of 1988, (or other datum, when specified) 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 identifiable water in a creek, brook, stream, river, ditch, or other similar feature.
ZONE A. A high risk special flood hazard area shown on the county’s flood insurance rate map developed using approximate study methods and therefore no base flood elevations are provided.
ZONE AE. A high-risk special flood hazard area shown on the county’s flood insurance rate map developed using detailed study methods and includes base flood elevations.
ZONE X. An area of minimal flood hazard depicted on the county’s flood insurance rate map as all areas outside of the A Zones. ZONE X may still have flooding that does not meet the criteria to be mapped as a special flood hazard area, especially ponding and local drainage problems. ZONE X replaces Zone C of the previous FIRM.
(Ord. 2106-34, passed 6-22-2021)