[Code of Federal Regulations]

[Title 24, Volume 1]

[Revised as of April 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 24CFR55.2]



[Page 400-401]

 

                 TITLE 24--HOUSING AND URBAN DEVELOPMENT

 

PART 55_FLOODPLAIN MANAGEMENT--Table of Contents

 

                            Subpart A_General

 

Sec.  55.2  Terminology.



    (a) With the exception of those terms defined in paragraph (b) of 

this section, the terms used in this part shall follow the definitions 

contained in section 6 of Executive Order 11988 and in the Floodplain 

Management Guidelines for Implementing Executive Order 11988 (43 FR 

6030, February 10, 1978) issued by the Water Resources Council; and the 

terms ``criteria'' and ``Regular Program'', shall follow the definitions 

contained in FEMA regulations at 44 CFR 59.1.

    (b) The definitions of the following terms in Executive Order 11988 

and related documents affecting this part are modified for purposes of 

this part:

    (1) Coastal high hazard area means the area subject to high velocity 

waters, including but not limited to hurricane wave wash or tsunamis. 

The area is designated on a Flood Insurance Rate Map (FIRM) under FEMA 

regulations as Zone V1-30, VE, or V. (FIRMs as well as Flood Hazard 

Boundary Maps (FHBM) shall also be relied on for the delineation of 

``100-year floodplains'' (Sec.  55.2(b)(8)), ``500-year floodplains'' 

(Sec.  55.2(b)(3)), and ``floodways'' (Sec.  55.2(b)(4)).

    (2)(i) Critical action means any activity for which even a slight 

chance of flooding would be too great, because such flooding might 

result in loss of life, injury to persons, or damage to property. 

Critical actions include activities that create, maintain or extend the 

useful life of those structures or facilities that:

    (A) Produce, use or store highly volatile, flammable, explosive, 

toxic or water-reactive materials;

    (B) Provide essential and irreplaceable records or utility or 

emergency



[[Page 401]]



services that may become lost or inoperative during flood and storm 

events (e.g., data storage centers, generating plants, principal utility 

lines, emergency operations centers including fire and police stations, 

and roadways providing sole egress from flood-prone areas); or

    (C) Are likely to contain occupants who may not be sufficiently 

mobile to avoid loss of life or injury during flood or storm events, 

e.g., persons who reside in hospitals, nursing homes, convalescent 

homes, intermediate care facilities, board and care facilities, and 

retirement service centers. Housing for independent living for the 

elderly is not considered a critical action.

    (ii) Critical actions shall not be approved in floodways or coastal 

high hazard areas.

    (3) 500-year floodplain means the minimum floodplain of concern for 

Critical Actions and is the area subject to inundation from a flood 

having a 0.2 percent chance of occurring in any given year. (See Sec.  

55.2(b)(1) for appropriate data sources.)

    (4) Floodway means that portion of the floodplain which is effective 

in carrying flow, where the flood hazard is generally the greatest, and 

where water depths and velocities are the highest. The term ``floodway'' 

as used here is consistent with ``regulatory floodways'' as identified 

by FEMA. (See Sec.  55.2(b)(1) for appropriate data sources.)

    (5) Functionally dependent use means a land use that must 

necessarily be conducted in close proximity to water (e.g., a dam, 

marina, port facility, water-front park, and many types of bridges).

    (6) High hazard area means a floodway or a coastal high hazard area.

    (7) 100-year floodplain means the floodplain of concern for this 

part and is the area subject to a one percent or greater chance of 

flooding in any given year. (See Sec.  55.2(b)(1) for appropriate data 

sources.)

    (8)(i) Substantial improvement means either:

    (A) Any repair, reconstruction, modernization or improvement of a 

structure, the cost of which equals or exceeds 50 percent of the market 

value of the structure either:

    (1) Before the improvement or repair is started; or

    (2) If the structure has been damaged, and is being restored, before 

the damage occurred; or

    (B) Any repair, reconstruction, modernization or improvement of a 

structure that results in an increase of more than twenty percent in the 

number of dwelling units in a residential project or in the average peak 

number of customers and employees likely to be on-site at any one time 

for a commercial or industrial project.

    (ii) Substantial improvement may not be defined to include either:

    (A) Any project for improvement of a structure to comply with 

existing state or local health, sanitary or safety code specifications 

that is solely necessary to assure safe living conditions, or

    (B) Any alteration of a structure listed on the National Register of 

Historical Places or on a State Inventory of Historic Places.

    (iii) Structural repairs, reconstruction, or improvements not 

meeting this definition are considered ``minor improvements''.