FLOOD07643

• County: Statewide
• Basin: Statewide
• Title: Physical and Economic Feasibility of Nonstructural Flood Plain Management Measures
• Date: 3/1/1978
• Prepared For: US
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Educational/Technical/Reference Information

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CHAPTER 11

ZONING ORDINANCES, SUBDIVISION REGULATIONS, AND
BUILDING AND HOUSING CODES

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Description
Through proper land use regulation, flood plains can be managed to insure that their use is
compatible with the severity of a flood hazard. Several means of regulation are available and
three will be discussed in this chapter: zoning ordinances, subdivision regulations, and building
and housing codes. Their purpose is to reduce losses by controlling future use, and changes in
existing use, of flood plain lands.

The following descriptions are taken from the Water Resources Council's study on
"Regulation of Flood Hazard Areas to Reduce Flood Losses" (Part 1, page 16, Volume I).

Zoning - "Zoning involves the division of a governmentai unit into districts and the regulation,
within these districts, of: (1) the'use of structures and land; (2) the height and bulk of structures;
and (3) the size of lots and density of use. The characteristic feature of zoning that distinguishes
it from other police power controls is that the regulations differ from district to district. For this
reason it can be used to set special standards for land uses in flood hazard areas. The division
into districts of lands throughout a community is usually based upon some broad land use plan
to guide the growth of the community." See Figure 11-1.

"The flood plain regulations contained in a zoning ordinance, much like the other operative
ordinance provisions, consist of two parts: (1) a written text which sets forth the regulations
which apply to each district together with administrative provisions; and (2) a map delineating
the boundaries of the various use districts. The important aspect of zoning is that it can be used
to regulate what uses may be conducted in flood hazard areas, where specific uses may be
conducted, and how uses are to be constructed or carried out. Zoning can be used to restrict
riverine or coastal areas to particular uses, specify where the uses may be located, and establish
minimum elevation or floodproofing requirements for the uses." See Figure 11-2 for an example
zoning ordinance.

Subdivision Regulations - "Subdivision regulations guide the division of large parcels of land
into smaller lots for the purpose of sale of building development. The regulations require that
the subdivider prepare a plat - a detailed map of the proposed subdivision land. The plat must
be approved by the local regulatory agency, usually the planning board, before the plat is
recorded and lots are sold. The agency checks the plat for compliance with subdivision
regulations, the local master plan, the zoning ordinance, and other regulations. A proposed
subdivision plat is typically reviewed to determine the adequacy of the street system; length of
depth of blocks; width and length of lots; provision for parks and open spaces; sufficiency of
water and sewerage systems; adequacy of drainage; safety from flood or other hazards; and
additional specifications set forth in the ordinance. Subdivision regulations with special
reference to flood hazards often (1) require installation of adequate drainage facilities, (2)
require that location of flood hazard areas be shown on the plat, (3) prohibit encroachment in
floodway areas, (4) require filling of a portion of each lot to provide a safe building site at
elevation above seiected flood heights or provide for open support elevation to achiev" the
same ends, and (5) require the placement of streets and public utilities above a selected flood
protection elevation. Figure 11-3 shows an example of a subdivision regulation.

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