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Unless specifically defined below, words or phrases used in this title shall be interpreted so as to give them the meaning they have in common usage and to give this title its most reasonable application:
ACCESSORY USE: A use which is incidental and subordinate to the principal use of the parcel of land on which it is located.
ALLUVIAL FAN: A geomorphologic feature characterized by a cone or fan-shaped deposit of clay, silt, sand, gravel, and boulders that have been eroded from mountain slopes, transported by flood flows, and deposited on the valley floor.
ALLUVIAL FAN FLOODING: Flooding occurring on the surface of an alluvial fan or similar landform which originates at the apex and is characterized by high velocity flows, active processes of erosion, sediment transport, deposition, and unpredictable flow paths.
ANCHOR: A series of methods used to secure a structure to its footings or foundation wall so that it will not be displaced by flood or wind forces.
APEX: The highest 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.
APPEAL: A request for a review of the flood plain administrator's interpretation of any provisions of this title.
AREA OF SHALLOW FLOODING: Designated zones AO and AH on a community's flood insurance rate map (FIRM) with a one percent (1%) or greater annual chance of flooding to an average depth of one foot (1') to three feet (3') 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 which is most likely to be subject to serve flood- related erosion losses. The area may be designated as zone E on the flood insurance rate map (FIRM).
BACKWATER EFFECT: The rise in water surface elevation caused by some obstruction such as a narrow bridge opening, buildings or fill material that limits the area through which the water must flow.
BASE FLOOD: A flood which has a one percent (1%) chance of being equalled or exceeded in any given year.
BASE FLOOD ELEVATION: The height in relation to mean sea level expected to be reached by the waters of the base flood at pertinent points in the flood plain of riverine areas.
BASE FLOOD PLAIN: The flood plain that would be inundated by a one percent (1%) chance flood.
BASEMENT: Any area of the building having its flood subgrade (below ground level) on all sides.
BREAKAWAY WALLS: 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.
CHANNEL: A natural or artificial watercourse with definite bed and banks to confine and conduct flowing water.
CHANNEL CAPACITY: The maximum flow that can pass through a channel without overflowing the banks.
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.
COMMUNITY: Any state or area or political subdivision thereof, or any Indian tribe or authorized tribal organization, or authorized native organization, which has authority to adopt and enforce flood plain management regulations for the areas within its jurisdiction.
CONDITIONAL LETTER OF MAP REVISION (CLOMR): Procedures by which contractors, developers and communities can request review and determination by the federal insurance administrator of scientific and technical data for a proposed project, when complete and functioning effectively, would modify the elevation of individual structures and parcels of land, stream channels, and flood plains on the FIRM.
CRITICAL STRUCTURES: A structure for which even a slight chance of flooding would reduce or eliminate its designed function of supporting a community in an emergency. Fire stations, hospitals, municipal airports, police stations, communication antennas or towers, elderly care facilities (old folks homes), fuel storage facilities, schools designated as emergency shelters, fresh water and sewage treatment facilities are some examples of critical structures.
DESIGNATED FLOODWAY: The channel of a stream and the portion of the adjoining flood plain designated by a regulatory agency to be kept free of further development to provide for unobstructed passage of flood flows.
DEVELOPMENT: Any manmade change to improved or unimproved real estate, including, but not limited to, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials.
DRY PROOFING: A floodproofing method used to design and construct buildings so as to prevent the entrance of floodwaters.
ENCROACHMENT: Any physical object placed in the flood plain that hinders the passage of water or otherwise affects flood flows, such as fill, excavation, storage of equipment and materials or buildings.
EROSION: The process of the gradual wearing away of any land mass.
EXISTING MANUFACTURED HOME (MOBILE 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 flood plain management regulations adopted by a community.
EXPANSION TO A MANUFACTURED HOME (MOBILE HOME) PARK: 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, construction of streets, and either final site grading or the pouring of concrete pads).
FEDERAL INSURANCE ADMINISTRATION (FIA): The government unit, a part of federal emergency management agency (FEMA), that administers the national flood insurance program (NFIP).
FEDERAL REGISTER: A document published daily by the federal government that provides a uniform system for making available to the public regulations and legal notices issued by federal agencies.
FLASH FLOOD: A flood that crests in a short length of time and is often characterized by high velocity flows. It is often the result of heavy rainfall in a localized area.
FLOOD BOUNDARY FLOODWAY MAP (FBFM): The official map of a community where the boundaries of the flood, mudslide and related erosion areas having special hazards have been designated as zones A, M and E.
FLOOD CONTROL: Keeping floodwaters away from specific developments or populated areas by the construction of flood storage reservoirs, channel alterations, dikes and levees, bypass channels, or other engineering works.
FLOOD FREQUENCY: A statistical expression of the average time period between floods equalling or exceeding a given magnitude.
FLOOD INSURANCE RATE MAP (FIRM): The official map 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.
FLOOD INSURANCE STUDY (FIS): A document containing the results of and examination, evaluation and determination of flood hazards and, if appropriate, corresponding water surface elevations, mudslides and erosion hazards.
FLOOD OR FLOODWATERS: A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland waters; the unusual and rapid accumulation or runoff of surface waters from any source and mudslides.
FLOOD PLAIN ADMINISTRATOR: The individual appointed to administer and enforce the flood plain management regulations.
FLOOD PLAIN AND FLOOD-PRONE AREA: Any land area susceptible to being inundated by waters from any source.
FLOOD PLAIN 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 flood plain, including, but not limited to, emergency preparedness plans, flood control works and flood plain management regulations and ordinances.
FLOOD PLAIN MANAGEMENT REGULATIONS: This title, and any federal, state or local regulations plus other zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances (such as a grading and erosion control) and other application of police power which control development in flood-prone areas for preventing and reducing flood loss and damage.
FLOOD-RELATED EROSION: The collapse or subsidence of land along the shore of a lake or other body of water as a result of 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 a flash flood or an abnormal tidal surge, or by some similarly unusual and unforeseeable event which results in flooding.
FLOOD-RELATED EROSION AREA MANAGEMENT: The operation of an overall program of corrective and preventive measures for reducing flood-related erosion damage, including, but not limited to, emergency preparedness plans, flood-related erosion control works, and flood plain management regulations.
FLOOD-RELATED EROSION PRONE AREA: A land area adjoining the shore of a lake or other body of water, which due to the composition of the shoreline or bank and high water levels or wind-driven currents, is likely to suffer flood-related erosion damage.
FLOOD ZONE A: An area of special flood hazard without water surface elevations determined.
FLOOD ZONE AH: An area of special flood hazard having shallow water depths and/or unpredictable flow paths between one foot (1') and three feet (3') and with water surface elevations determined.
FLOOD ZONE AO: An area of special flood hazard having shallow water depths and/or unpredictable flow paths between one foot (1') and three feet (3').
FLOOD ZONE A-99: An area of special flood hazard where enough progress has been made on a protective system, such as dikes, dams and levees, to consider it complete for insurance rating purposes.
FLOOD ZONE D: An area of undetermined but possible flood hazard.
FLOOD ZONE E: An area of special flood-related erosion hazards.
FLOOD ZONE M: An area of special mudslide or mudflow hazards.
FLOOD ZONES: Zones on the flood insurance rate map (FIRM) in which the risk premium insurance rates have been established by a flood insurance study.
FLOOD ZONES A1-30 AND AE: Areas of special flood hazard with water surface elevations determined.
FLOOD ZONES B AND SHADED X: Areas of moderate flood hazard.
FLOOD ZONES C AND UNSHADED X: Areas of minimal hazard.
FLOODPROOFING: Any combination of structural and nonstructural additions, changes, or adjustments to structures which reduce or eliminate flood damage to real estate or improved property, water and sanitary facilities, structures and their contents.
FLOODWAY: The channel of a river or other watercourse and the adjacent land area that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height.
FLOODWAY ENCROACHMENT LINES: The lines marking the limits of floodways on federal, state and local flood plain maps.
FLOODWAY FRINGE: The area of the flood plain on either side of the regulatory floodway where encroachment may be permitted.
FOOTING: The enlarged base of a fountain wall, pier or column, designed to spread the load of the structure so that it does not exceed the soil bearing capacity.
FOUNDATION: The underlying structure of a building, usually constructed of concrete, that supports the foundation walls, piers or columns.
FOUNDATION WALLS: A support structure that connects the foundation to the main portion of the building or superstructure.
FRAUD/VICTIMIZATION: Related to variances of this title. The variance granted must not cause fraud on or victimization to the public. In examining this requirement, the city will consider the fact that every newly constructed building adds to government responsibilities and remains a part of the community for fifty (50) to one hundred (100) years. Buildings permitted to be constructed below the base flood elevation are subject during all those years to increased risk of damage from floods, while future owners of the property and the community as a whole are subject to all the costs, inconvenience, danger, and suffering that those increased flood damages bring. Additionally, future owners may be unaware of the risk potential to the property due to flood damage and the extremely high rates for flood insurance.
FREEBOARD: A margin of safety usually expressed in feet above a flood level for purposes of flood plain 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.
GOVERNING BODY: The local governing unit, county or municipality, that is empowered to adopt and implement regulations to provide for public health, safety and general welfare of its citizenry.
HARDSHIP: Related to variances of this title. The exceptional hardship would result from a failure to grant the requested variance. The city requires the variance be 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 ground surface prior to construction next to the proposed walls of a structure.
HISTORIC STRUCTURE: Any structure that is:
A. 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;
B. 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; 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
C. Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either by an approved state program as determined by the secretary of the interior or directly by the secretary of the interior in states without approved programs.
HYDRAULICS: The science that deals with practical applications of water in motion.
HYDRODYNAMIC LOADS: Forces imposed on structures by flood waters due to the impact of moving water on the upstream side of the structure, drag along its sides, and eddies or negative pressures on its downstream side.
HYDROGRAPHY: A graph that charts the passage of water as a function of time. It shows flood stages, depicted in feet above mean sea level or gauge height plotted against stated time intervals.
HYDROLOGY: The science of the behavior of water in the atmosphere, on the earth's surface, and underground.
HYDROSTATIC LOADS: Forces imposed on a flooded structure due to the weight of the water.
LETTER OF MAP AMENDMENT (LOMA): The procedure by which any owner or lessee of property who believes his property has been inadvertently included in a special flood hazard area can submit scientific and technical information to the federal insurance administrator for review to remove the property from said area. The administrator will not consider a LOMA if the information submitted is based on alteration of topography or new hydrologic or hydraulic conditions since the effective date of the FIRM.
LETTER OF MAP REVISION (LOMR): The procedures by which contractors, developers and communities can request changes to flood zones, flood plain and floodway delineations, flood elevations, and planimetric features based on the results of structural works, improvements or annexations resulting in additional flood hazard areas.
LEVEE: A manmade 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 which consists of a levee, or levees, and associated structures, such as closure and drainage devices, which are constructed and operated in accord with sound engineering practices.
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; provided, that such enclosure is not built so as to render the structure in violation of the applicable nonelevation design requirements of this title. Attached garages are allowed to be built at grade. Below-grade garages are not allowed as they are considered to be basements.
MANUFACTURED HOME (MOBILE 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 "recreational vehicles."
MANUFACTURED HOME PARK OR SUBDIVISION: A parcel or contiguous parcels of land divided into two (2) or more manufactured home lots for rent or sale.
MEAN SEA LEVEL: For the 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 flood insurance rate map are referenced.
MOBILE HOME: The same as manufactured home.
MUDSLIDE: A condition where there is a river, flow or inundation of liquid mud down a hillside usually as a result of a dual condition of loss of brush cover, and the subsequent accumulation of water on the ground preceded by a period of unusually heavy or sustained rain. A mudslide may occur as a distinct phenomenon while a landslide is in progress, and will be recognized as such by the federal insurance administrator only if the mudflow, and not the landslide, is the proximate cause of damage that occurs.
MUDSLIDE PRONE AREA: An area with land surfaces and slopes of unconsolidated material where the history, geology and climate indicate a potential for mudflows.
NATIONAL GEODETIC VERTICAL DATUM (NGVD): As corrected in 1929, is a vertical control used as a reference for establishing varying elevations within the flood plain.
NEW CONSTRUCTION: For flood plain management purposes, structures for which the start of construction commenced on or after the effective date of these flood plain management regulations adopted by the city, 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 these flood plain management regulations adopted by the city.
OBSTRUCTION: Includes, but is not limited to, any dam, wall, wharf, embankment, levee, dike, pile, abutment, protection, excavation, channelization, 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.
100-YEAR FLOOD: The same as base flood.
PRINCIPAL STRUCTURE: A structure used for the principal use of the property as distinguished from an accessory use.
PUBLIC SAFETY/NUISANCE: Related to variances of the title. The granting of a variance must not result in anything which is injurious to safety or health of the entire community or 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 built on a single chassis, four hundred (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.
RIVERINE: Relating to, formed by, or resembling a river, including tributaries, stream, brook, etc.
SHEET FLOW AREA: The same as "area of shallow flooding".
SPECIAL FLOOD HAZARD AREA: An area having special flood, mudslide, or flood-related erosion hazards, and shown on an FHBM or FIRM in zones A, AO, Al, A30, AE, A99, AH, E or M.
START OF CONSTRUCTION: Includes substantial improvement and other proposed new development 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 one hundred eighty (180) days from the date of the permit. 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 that alteration affects the external dimensions of the building.
STRUCTURE: A walled and roofed building that is principally above ground and includes gas or liquid storage tank and manufactured homes.
SUBSTANTIAL DAMAGE: Damage of any origin sustained by a structure whereby the cost of restoring the structure to its before-damage condition would equal or exceed fifty percent (50%) of the market value of the structure before the damage occurred.
SUBSTANTIAL IMPROVEMENT: Any reconstruction, rehabilitation, addition, or other proposed new development of a structure, the cost of which equals or exceeds fifty percent (50%) 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 term does not, however, include either:
A. 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
B. Any alteration of an historic structure; provided, that the alteration will not preclude the structure's continued designation as an historic structure.
VARIANCE: A grant of relief from the requirements of this title which permits construction in a manner that would otherwise be prohibited by this title.
WATER SURFACE ELEVATION: The height, in relation to the national geodetic vertical datum (NGVD) of 1929, or other datum, where specified of floods of various magnitudes and frequencies in the flood plains of coastal or riverine areas.
WATERCOURSE: A lake, river, creek, stream, wash, arroyo, 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. (1973 Code § 18.02.010)