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 and deposition; and unpredictable flow paths.

Any work within a stream such as bridges, culverts, etc., or change in the flow path or carrying capacity of a stream.

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.

A structure which is located on the same parcel of property as the principal structure and the use of which is incidental to the use of the principal structure. Appurtenant structures should constitute a minimal investment, may not be used for human habitation, and be designed to have minimal flood damage potential. Examples of appurtenant structures are detached garages, carports, storage sheds, pole barns and hay sheds.

A designated AH, AO or VO zone with a one percent (1%) or greater annual chance of flooding to an average depth of one to three feet (1' - 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.

The flood having a one percent (1%) chance of being equaled or exceeded in any given year.

The computed elevation to which floodwater is anticipated to rise during the base flood. Base flood elevations (BFEs) are shown on flood insurance rate maps FIRMs and on the flood profiles.

Any area of the building having its floor subgrade (below ground level) on all sides.

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 the supporting foundation system.

An integral and readily identifiable part of a flood protection system, without which the flood protection provided by the entire system would be compromised.

Any manmade change to improved or unimproved real estate, including, but not limited to, flood control structures, buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations or storage of equipment or materials located within the special flood hazard area.

A.   A nonbasement building which is:

   1.   Built, in the case of a building in zones A1-30, AE, A, A99, AO, AH, B, C, X and D, to have the top of the elevated floor, or in the case of a building in zones V1-30, VE or V, to have the bottom of the lowest horizontal structure member of the elevated floor elevated above the ground level by means of pilings, columns (posts and piers), or shear walls parallel to the floor of the water; and

   2.   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.

B.   In the case of zones A1-30, AE, A, A99, AO, AH, B, C, X and D, "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.

C.   In the case of zones V1-30, VE or V, "elevated building" also includes a building otherwise meeting the definition of "elevated building", even though the lower area is enclosed by means of breakaway walls if the breakaway walls meet the standards of section 60.3(e)(5) of the National Flood Insurance Program regulations.

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".

A manufactured home park 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) are completed before the effective date hereof.

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).

A general and temporary condition of partial or complete inundation of normally dry land areas from:

A.   The overflow of inland or tidal waters;

B.   The unusual and rapid accumulation or runoff of surface waters from any source; or

C.   Mudslides (i.e., mudflows) which are proximately caused by flooding as defined in subsection B 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.

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.

The official map on which the federal emergency management agency has delineated both special flood hazard areas and the risk premium zones applicable to the city.

The official report provided by the federal emergency management agency that includes flood profiles, the flood boundary floodway map, and the water surface elevation of the base flood.

Those 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 area within a community subject to a "special flood hazard" and the extent of the depths of associated flooding. Such a system typically includes hurricane tidal barriers, dams, reservoirs, levees or dikes. These specialized flood modifying works are those constructed in conformance with sound engineering standards.

Any land area susceptible to being inundated by water from any source (see definition of FLOOD OR FLOODING).

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.

Any state law or city ordinance, including Farmington City zoning ordinances, subdivision regulations, building codes, health regulations, special purpose ordinances, such as this floodplain ordinance, etc., which provide standards for the purpose of flood damage prevention and reduction.

Any combination of structural and nonstructural 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.

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 one foot (1').

A use which 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 shipbuilding and ship repair facilities, but does not include long term storage or related manufacturing facilities.

The highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.

Any structure that is:

A.   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;

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.

Forces imposed on structures by floodwaters 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.

Loads or pressures resulting from the static mass of water at any point of floodwater contact with a structure. They are equal in all directions and always act perpendicular to the surface on which they are applied.

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.

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 accordance with sound engineering practices.

The lowest point of the ground level immediately next to a building.

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 or crawl space 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 chapter.

A structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term "manufactured home" does not include a "recreational vehicle".

A parcel (or contiguous parcels) of land divided into two (2) or more manufactured home lots for rent or sale.

For purposes of the national flood insurance program, the North American vertical datum (NAVD) of 1988 or other datum, to which base flood elevations shown on a community' s flood insurance rate map are referenced.

For purposes of determining insurance rates, structures for which the "start of construction" commenced on or after the effective date of the city's initial FIRM, and includes any subsequent improvements to such structures. For floodplain management purposes, "new construction" means structures for which the "start of construction" commenced on or after the effective date hereof, and includes any subsequent improvements to such structures.

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 hereof.

A vehicle which is: a) built on a single chassis; b) four hundred (400) square feet or less when measured at the largest horizontal projections; c) designed to be self-propelled or permanently towable 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.

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 one foot (1').

The land in the floodplain subject to a one percent (1%) or greater chance of flooding in any given year.

Includes substantial improvement, and means the date the building permit was issued, provided the actual start of construction, repair, reconstruction, placement or other improvement was within one hundred eighty (180) days of the permit date. The actual start means 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 or 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.

A walled and roofed building or manufactured home that is principally aboveground.

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 the market value of the structure before the damage occurred.

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 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".

A grant of relief from the requirements of this chapter which permits construction in a manner that would otherwise be prohibited by this chapter.

Failure to comply with any of the terms and conditions of this chapter.

The height, in relation to the North American Vertical Datum (NAVD) of 1988 (or other datum, where specified), of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas. (Ord. 2007-34, 7-17-2007; amd. Ord. 2019-29, 9-17-2019; Ord. 2022-48, 9-6-2022)