13-1-2: DEFINITIONS:
Unless specifically defined in this section, words or phrases used in this chapter shall be interpreted according to the meaning they have in common usage, as well as to give this chapter its most reasonable application.
ACCESSORY STRUCTURE (APPURTENANT STRUCTURE): A structure on the same lot or parcel as a principal structure, the use of which is incidental and subordinate to the principal structure.
APPEAL: A request for review of the floodplain administrator's interpretation of the provisions of this chapter, or a request for a variance.
BASE FLOOD: The flood having a one percent (1%) chance of being equaled or exceeded in any given year.
BASE FLOOD ELEVATION (BFE): A determination by the federal insurance administrator of the water surface elevations of the base flood, that is, the flood level that has a one percent (1%) or greater chance of occurrence in any given year. When the BFE has not been provided in a special flood hazard area, it may be obtained from engineering studies available from a federal, state, or other source using FEMA approved engineering methodologies. This elevation, when combined with the freeboard, establishes the flood protection elevation.
BASEMENT: Any area of the building having its floor subgrade (below ground level), including crawl space, on all sides.
DATUM: The vertical datum is a base measurement point (or set of points) from which all elevations are determined. Historically, that common set of points has been the national geodetic vertical datum of 1929 (NGVD29). The vertical datum currently adopted by the federal government as a basis for measuring heights is the North American vertical datum of 1988 (NAVD88).
DEVELOPMENT: 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.
ELEVATION CERTIFICATE: The elevation certificate is an important administrative tool of the NFIP. It is used to determine the proper flood insurance premium rate; it is used to document elevation information necessary to ensure compliance with community floodplain management regulations; and it may be used to support a request for a letter of map amendment (LOMA) or letter of map revision based on fill (LOMR-F).
FEDERAL EMERGENCY MANAGEMENT AGENCY (FEMA): The agency with the overall responsibility for administering the national flood insurance program.
FLOOD FRINGE: The portion of the floodplain outside of the floodway covered by floodwaters during the regulatory flood.
FLOOD INSURANCE RATE MAP (FIRM): An official map of a community, on which the federal insurance administrator has delineated both the special hazard areas 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): 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.
FLOOD OR FLOODING: A. A general and temporary condition of partial or complete inundation of normally dry land areas from:
  1. The overflow of inland or tidal waters.
  2. The unusual and rapid accumulation or runoff of surface waters from any source.
  3. Mudslides (i.e., mudflows) which are proximately caused by flooding as defined in subsection A2 of this definition 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.
   B.   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 in subsection A1 of this definition.
FLOOD PROTECTION ELEVATION (FPE): The base flood elevation plus the freeboard.
   A.   In "special flood hazard areas" where base flood elevations (BFEs) have been determined, this elevation shall be the BFE of 2246.8 feet plus two feet (2') of freeboard; and
   B.   In "special flood hazard areas" where no BFE has been established, this elevation shall be the BFE of 2246.8 feet plus two feet (2') of freeboard.
FLOODPLAIN: The land that has been or may be covered by floodwaters, or is surrounded by floodwater and inaccessible, during the occurrence of the regulatory flood.
FLOODPLAIN DEVELOPMENT PERMIT: Any type of permit that is required in conformance with the provisions of this chapter, prior to the commencement of any development activity.
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.
FREEBOARD: A factor of safety usually expressed in feet above a flood level for the purposes of floodplain management. Freeboard tends to compensate for the many unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, obstructed bridge openings, debris and ice jams, and the hydrologic effects of urbanization in a watershed. The base flood elevation (BFE) plus the freeboard establishes the flood protection elevation (FPE). Freeboard shall be two feet (2').
FUNCTIONALLY DEPENDENT FACILITY: A facility that cannot be used for its intended purpose unless it is located or carried out in the close proximity to water, such as a docking or port facility necessary for the loading and unloading of cargo or passengers, shipbuilding, or ship repair facilities. The term does not include long term storage, manufacture, sales, or service facilities.
HIGHEST ADJACENT GRADE (HAG): The highest natural elevation of the ground surface prior to construction, adjacent to the proposed walls of a structure. Refer to the FEMA elevation certificate for HAG related to building elevation information.
HISTORIC STRUCTURE: A structure that is:
   A.   Listed individually in the national register of historic places (a listing maintained by the U.S. department of the interior) or preliminarily determined by the secretary of the interior as meeting the requirements for individual listing on the national register.
   B.   Certified or preliminarily determined by the secretary of the interior as contributing to the historical significance of a registered historic district or to a district preliminarily determined by the secretary to qualify as a registered historic district.
   C.   Individually listed on a state inventory of historic places and determined as eligible by states with historic preservation programs which have been approved by the secretary of the interior, or
   D.   Individually listed on a local inventory of historic places and determined as eligible by communities with historic preservation programs that have been certified either:
  1. By an approved state program as determined by the secretary of the interior, or
  2. Directly by the secretary of the interior in states without approved programs.
LETTER OF MAP CHANGE (LOMC): A general term used to refer to the several types of revisions and amendments to FEMA maps that can be accomplished by letter. They include letter of map amendment (LOMA), letter of map revision (LOMR), and letter of map revision based on fill (LOMR-F).
   A.   Letter Of Map Amendment (LOMA): An official amendment, by letter, to an effective national flood insurance program (NFIP) map. An LOMA establishes a property's location in relation to the special flood hazard area (SFHA). LOMAs are usually issued because a property has been inadvertently mapped as being in the floodplain but is actually on natural high ground above the base flood elevation.
   B.   Letter Of Map Revision (LOMR): A revision based on technical data showing, usually due to manmade changes, changes to flood zones, flood elevations, floodplain and floodway delineations, and planimetric features.
   C.   Letter Of Map Revision Based On Fill (LOMR-F): FEMA's modification of the special flood hazard area (SFHA) shown on the flood insurance rate map (FIRM) based on the placement of fill outside the existing regulatory floodway. The LOMR-F does not change the FIRM, FBFM, or FIS report.
LOWEST ADJACENT GRADE (LAG): The lowest point of the ground level next to the structure. Refer to the FEMA elevation certificate for LAG related to building elevation information.
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 44 CFR section 60.3 and this chapter.
MANUFACTURED HOME: A structure, transportable in one or more sections, built on a permanent chassis and designed to be used with or without a permanent foundation when connected to the required utilities. The term "manufactured home" does not include a "recreational vehicle".
MEAN SEA LEVEL: For purposes of the national flood insurance program, the national geodetic vertical datum (NGVD) of 1929 or other datum, to which base flood elevations shown on a community's FIRM are referenced.
NEW CONSTRUCTION: A structure for which the "start of construction" commenced after May 3, 2010, and includes subsequent improvements to the structure.
RECREATIONAL VEHICLE: A vehicle that is:
   A.   Built on a single chassis, and
   B.   Four hundred (400) square feet or less when measured at the largest horizontal projection, and
   C.   Designed to be self-propelled or permanently towed by a light duty truck, and
   D.   Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use.
SPECIAL FLOOD HAZARD AREA (SFHA): The land in the floodplain within a community subject to a one percent (1%) or greater chance of flooding in any given year. For purposes of these regulations, the term "special flood hazard area" is synonymous in meaning with the phrase "area of special flood hazard".
START OF CONSTRUCTION: Includes substantial improvement and means the date the development permit was issued, provided the actual start of construction, repair, reconstruction, or improvement was within one hundred eighty (180) days of the permit date. The actual start means either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading, and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, or foundations or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not the alteration affects the external dimensions of a building.
STRUCTURE: A walled and roofed building, including a gas or liquid storage tank that 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 fifty percent (50%) of its market value before the damage occurred. See definition of Substantial Improvement.
SUBSTANTIAL IMPROVEMENT: Any reconstruction, rehabilitation, addition, or other improvement 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 market value of the structure should be: a) the appraised value of the structure prior to the start of the initial repair or improvement, or b) in the case of damage, the value of the structure prior to the damage occurring. This term includes structures which have incurred "substantial damage", regardless of the actual amount of 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 a "historic structure", provided that the alteration will not preclude the structure's continued designation as a "historic structure" and the alteration is approved by variance issued pursuant to this chapter.
VARIANCE: A modification of the bulk and placement requirements of this chapter as to lot size, lot coverage, width, depth, front yard, side yard, rear yard, setbacks, parking space, height of buildings, or other ordinance provision affecting the size or shape of a structure or the placement of the structure upon lots, or the size of lots.
ZONE A: Areas subject to inundation by the one percent (1%) annual chance flood event generally determined using approximate methodologies. Because detailed hydraulic analyses have not been performed, no base flood elevations (BFEs) or flood depths are shown. Mandatory flood insurance purchase requirements and floodplain management standards apply. The city of Hayden adopts the base flood elevation for the zone A of 2,246.8 feet per LOMCs 12-10-1356A, 11-10-0256A, and 12-10-1331A. (Ord. 564, 10-25-2016)