The following definitions shall apply throughout this regulation.

Action means any action or activity including: (a) Acquiring, managing and disposing of Federal lands and facilities; (b) providing federally undertaken, financed or assisted construction and improvements; and (c) conducting Federal activities and programs affecting land use, including, but not limited to, water and related land resources, planning, regulating and licensing activities.

Actions Affecting or Affected by Floodplains or Wetlands means actions which have the potential to result in the long- or short-term impacts associated with (a) the occupancy or modification of floodplains, and the direct or indirect support of floodplain development, or (b) the destruction and modification of wetlands and the direct or indirect support of new construction in wetlands.

Administrator means the Administrator of the Federal Emergency Management Agency.

Agency means the Federal Emergency Management Agency (FEMA).

Agency Assistance means grants for projects or planning activities, loans, and all other forms of financial or technical assistance provided by the Agency.

Base Flood means the flood which has a one percent chance of being equalled or exceeded in any given year (also known as a 100-year flood). This term is used in the National Flood Insurance Program (NFIP) to indicate the minimum level of flooding to be used by a community in its floodplain management regulations.

Base Floodplain means the 100-year floodplain (one percent chance floodplain).

Coastal High Hazard Area means the areas subject to high velocity waters including but not limited to hurricane wave wash or tsunamis. On a Flood Insurance Rate Map (FIRM), this appears as zone V1-30, VE or V.

Critical Action means an action for which even a slight chance of flooding is too great. The minimum floodplain of concern for critical actions is the 500-year floodplain, i.e., critical action floodplain. Critical actions include, but are not limited to, those which create or extend the useful life of structures or facilities:

(a) Such as those which produce, use or store highly volatile, flammable, explosive, toxic or water-reactive materials;

(b) Such as hospitals and nursing homes, and housing for the elderly, which are likely to contain occupants who may not be sufficiently mobile to avoid the loss of life or injury during flood and storm events;

(c) Such as emergency operation centers, or data storage centers which contain records or services that may become lost or inoperative during flood and storm events; and

(d) Such as generating plants, and other principal points of utility lines.

Direct Impacts means changes in floodplain or wetland values and functions and changes in the risk to lives and property caused or induced by an action or related activity. Impacts are caused whenever these natural values and functions are affected as a direct result of an action. An action which would result in the discharge of polluted storm waters into a floodplain or wetland, for example, would directly affect their natural values and functions. Construction-related activities, such as dredging and filling operations within the floodplain or a wetland would be another example of impacts caused by an action.

Emergency Actions means emergency work essential to save lives and protect property and public health and safety performed under sections 305 and 306 of the Disaster Relief Act of 1974 (42 U.S.C. 5145 and 5146). See 44 CFR part 205, subpart E.

Enhance means to increase, heighten, or improve the natural and beneficial values associated with wetlands.

Facility means any man-made or man-placed item other than a structure.

FEMA means the Federal Emergency Management Agency.

FIA means the Federal Insurance Administration.

Five Hundred Year Floodplain (the 500-year floodplain or 0.2 percent change floodplain) means that area, including the base floodplain, which is subject to inundation from a flood having a 0.2 percent chance of being equalled or exceeded in any given year.

Flood or flooding means a general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland and/or tidal waters, and/or the unusual and rapid accumulation or runoff of surface waters from any source.

Flood Fringe means that portion of the floodplain outside of the floodway (often referred to as “floodway fringe”).

Flood Hazard Boundary Map (FHBM) means an official map of a community, issued by the Administrator, where the boundaries of the flood, mudslide (i.e., mudflow) and related erosion areas having special hazards have been designated as Zone A, M, or E.

Flood Insurance Rate Map (FIRM) means an official map of a community on which the Administrator has delineated both the special hazard areas and the risk premium zones applicable to the community. FIRMs are also available digitally, and are called Digital Flood Insurance Rate Maps (DFIRM).

Flood Insurance Study (FIS) means 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 means the lowland and relatively flat areas adjoining inland and coastal waters including, at a minimum, that area subject to a one percent or greater chance of flooding in any given year. Wherever in this regulation the term “floodplain” is used, if a critical action is involved, “floodplain” shall mean the area subject to inundation from a flood having a 0.2 percent chance of occurring in any given year (500-year floodplain). “Floodplain” does not include areas subject only to mudflow until FIA adopts maps identifying “M” Zones.

Floodproofing means the modification of individual structures and facilities, their sites, and their contents to protect against structural failure, to keep water out, or to reduce effects of water entry.

Floodway means that portion of the floodplain which is effective in carrying flow, within which this carrying capacity must be preserved and where the flood hazard is generally highest, i.e., where water depths and velocities are the greatest. It is that area which provides for the discharge of the base flood so the cumulative increase in water surface elevation is no more than one foot.

Functionally Dependent Use means a use which cannot perform its intended purpose unless it is located or carried out in close proximity to water, (e.g., bridges, and piers).

Indirect Impacts means an indirect result of an action whenever the action induces or makes possible related activities which effect the natural values and functions of floodplains or wetlands or the risk to lives and property. Such impacts occur whenever these values and functions are potentially affected, either in the short- or long-term, as a result of undertaking an action.

Minimize means to reduce to the smallest amount or degree possible.

Mitigation means all steps necessary to minimize the potentially adverse effects of the proposed action, and to restore and preserve the natural and beneficial floodplain values and to preserve and enhance natural values of wetlands.

Mitigation Directorate means the Mitigation Directorate of the Federal Emergency Management Agency.

Natural Values of Floodplains and Wetlands means the qualities of or functions served by floodplains and wetlands which include but are not limited to: (a) Water resource values (natural moderation of floods, water quality maintenance, groundwater recharge); (b) living resource values (fish, wildlife, plant resources and habitats); (c) cultural resource values (open space, natural beauty, scientific study, outdoor education, archeological and historic sites, recreation); and (d) cultivated resource values (agriculture, aquaculture, forestry).

New Construction means the construction of a new structure (including the placement of a mobile home) or facility or the replacement of a structure or facility which has been totally destroyed.

New Construction in Wetlands includes draining, dredging, channelizing, filling, diking, impounding, and related activities and any structures or facilities begun or authorized after the effective dates of the Orders, May 24, 1977.

Orders means Executive Orders 11988, Floodplain Management, and 11990, Protection of Wetlands.

Practicable means capable of being done within existing constraints. The test of what is practicable depends upon the situation and includes consideration of all pertinent factors, such as environment, cost and technology.

Preserve means to prevent alterations to natural conditions and to maintain the values and functions which operate the floodplains or wetlands in their natural states.

Regional Administrator means the Regional Administrator of the Federal Emergency Management Agency for the Region in which FEMA is acting, or the Disaster Recovery Manager when one is designated.

Regulatory Floodway means the area regulated by federal, State or local requirements to provide for the discharge of the base flood so the cumulative increase in water surface elevation is no more than a designated amount (not to exceed one foot as set by the National Flood Insurance Program).

Restore means to reestablish a setting or environment in which the natural functions of the floodplain can again operate.

Structures means walled or roofed buildings, including mobile homes and gas or liquid storage tanks.

Substantial Improvement means any repair, reconstruction or other improvement of a structure or facility, which has been damaged in excess of, or the cost of which equals or exceeds, 50% of the market value of the structure or replacement cost of the facility (including all “public facilities” as defined in the Disaster Relief Act of 1974) (a) before the repair or improvement is started, or (b) if the structure or facility has been damaged and is proposed to be restored, before the damage occurred. If a facility is an essential link in a larger system, the percentage of damage will be based on the relative cost of repairing the damaged facility to the replacement cost of the portion of the system which is operationally dependent on the facility. The term “substantial improvement” does not include any alteration of a structure or facility listed on the National Register of Historic Places or a State Inventory of Historic Places.

Support means to encourage, allow, serve or otherwise facilitate floodplain or wetland development. Direct support results from actions within a floodplain or wetland, and indirect support results from actions outside of floodplains or wetlands.

Wetlands means those areas which are inundated or saturated by surface or ground water with a frequency sufficient to support, or that under normal hydrologic conditions does or would support, a prevalence of vegetation or aquatic life typically adapted for life in saturated or seasonally saturated soil conditions. Examples of wetlands include, but are not limited to, swamps, fresh and salt water marshes, estuaries, bogs, beaches, wet meadows, sloughs, potholes, mud flats, river overflows and other similar areas. This definition includes those wetlands areas separated from their natural supply of water as a result of activities such as the construction of structural flood protection methods or solid-fill road beds and activities such as mineral extraction and navigation improvements. This definition is intended to be consistent with the definition utilized by the U.S. Fish and Wildlife Service in the publication entitled Classification of Wetlands and Deep Water Habitats of the United States (Cowardin, et al., 1977).

[45 FR 59526, Sept. 9, 1980, as amended at 47 FR 13149, Mar. 29, 1982; 50 FR 40006, Oct. 1, 1985; 74 FR 15335, Apr. 3, 2009]


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