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<br />. The placement of streets and public utilities above the base .flood
<br />elevation
<br />
<br />The regulations that impose these performance standards on
<br />communities participating in the Nfl? are found at 44 CFR 60.3(a)(4),
<br />(b)(3), and (c){ll). The specific language of those requirements fo11oo's.
<br />
<br />(a)(4) [A community must] review subdivision proposals and
<br />other proposed new development, including
<br />manufachtred home parks or subdivisions, to determine
<br />whether such proposals ,,,,,ill be reasonably safe from
<br />flooding. If a subdivision proposal or other proposed
<br />new development is in a flood-prone area, any such
<br />proposals shall be reviewed to ensure that:
<br />i) all such proposals are consistent with the need to
<br />minimize flood damage within the flood-prone area;
<br />ii) all public utilities and facilities, such as sewer, gas,
<br />electrical, and water systems are located and constructed
<br />to minimize or eliminate flood damage; and
<br />iii) adequate drainage is provided to reduce exposure to
<br />flood hazards.
<br />
<br />(b)(3) All new subdivision proposals and other proposed
<br />developments (including proposals for manufactured home
<br />parks and subdivisions) greater than 50 lots or 5 acres,
<br />whichever is the lesser, [must] include within such proposals
<br />base flood elevation data.
<br />
<br />Note: If this information is not available from
<br />federal, state, or other sources, the developer may
<br />
<br />be required to hire an engineering firm to develop
<br />BFEs using methodologies comparable to those
<br />that would be used in a Flood Insurance Study.
<br />
<br />(c)(Il) Within Zones AH and AO, adequate drainage paths
<br />around struchtres on slopes, [must be provided] to guide
<br />floodwaters around and away from proposed structures. These
<br />drainage paths will generally have to be incorporated into the
<br />grading plan of the subdivision.
<br />
<br />In addition, the subdi'vision process must adequately address the
<br />requirements of CFR 60.3(c)(1O) and (d)(3) to ensure that
<br />encroachments do not occur in the regulatory floodway.
<br />Taken together, these criteria encourage communities to address
<br />the flooding hazards at the earliest stages of subdivision planning
<br />rather than tvhen individual structures are being constructed. if a
<br />community can work with the developer and others to subdivide
<br />land in the manner that least intrudes on the floodplain, many long-
<br />tenn floodplain management benefits call be achieved. In many
<br />instances, subdivisions can be designed to avoid the floodplain
<br />altogether.
<br />An important part of this comprehensive approach includes
<br />design considerations for locating utilities and other
<br />infrastructure within the subdivision to minimize not only flood
<br />damages, but also to allow homeowners to reoccupy their homes
<br />following a flooding event. This is particularly important when
<br />well-designed structures remain dry but are not habitable
<br />because water, electricity, and other services are not available due
<br />to umter damage to the utilities.
<br />
<br />NFl P Glosson!
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<br />The following are regulatory definitions and can be found at Section
<br />59.1 of the Nfl? regulations for floodplain management and flood
<br />hazard identification.
<br />
<br />base flood The flood having a 1 percent chance of being
<br />equaled or exceeded in any given year
<br />
<br />Base Flood Elevation (BFE) The elevation for which there is
<br />a 1 percent chance in any given year that flood levels will
<br />equal or exceed it. BFE is determined by statistical analysis of
<br />streamflow records for the watershed and rainfall and runoff
<br />characteristics in the general region of the watershed.
<br />
<br />coastal high-hazard area An area of special flood hazard
<br />extending from offshore to the inland limit of a primary
<br />frontal dune along an open coast and any other area subject to
<br />high-velocity wave action from storms or seismic sources
<br />
<br />community As defined for NFIP's purposes, any state, area,
<br />or political subdivision or any Native American tribe,
<br />authorized tribal organization, Alaska native village, or
<br />authorized native organization that has the authority to adopt
<br />and enforce floodplain management ordinances for the area
<br />under its jurisdiction
<br />
<br />Flood Insurance Rate Map (FIRM) An official map of a
<br />community, on which the Associate Director for Mitigation
<br />has delineated both the special hazard areas and the risk
<br />premium zones applicable to the community
<br />
<br />floodplain or flood-prone area Any land area susceptible to
<br />being inundated by water from any source
<br />
<br />floodplain management The operation of an overall
<br />program of corrective and preventive measures for reducing
<br />flood damage, including, but not limited to, emergency
<br />preparedness plans, flood control works, and floodplain
<br />management regulations
<br />
<br />floodplain management regulations Zoning ordinances,
<br />subdivision regulations, building codes, health regulations,
<br />
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<br />special purpose ordinances (such as a floodplain ordinance,
<br />grading ordinance, and erosion control ordinance), and other
<br />applications of police power. The term describes such state or
<br />local regulations, in any combination thereof, which provide
<br />standards for the purpose of flood damage prevention and
<br />reduction.
<br />
<br />lowest floor The lowest floor of the lowest enclosed area
<br />(including basement). An unfinished or flood-resistant enclosure,
<br />usable solely for parking of vehicles, building access, or storage
<br />in an area other than a basement area is not considered a
<br />building's lowest floor, provided that such enclosure is not built
<br />so as to render the struchtre in violation of the applicable
<br />nonelevation design requirements of 44 CPR Section 60.3.
<br />
<br />new construction For floodplain management purposes,
<br />struchtres for which the "start of construction" commenced on
<br />or after the effective date of a floodplain management
<br />regulation adopted by a community and includes any
<br />subsequent improvements to such structures
<br />
<br />regulatory floodway The channel of a river or other watercourse
<br />and the adjacent land areas that must be reserved in order to
<br />discharge the base flood without cumulatively increasing the
<br />water surface elevation more that a designated height
<br />
<br />Special Flood Hazard Area (SFHA) Land in the floodplain
<br />within a community subject to 1 percent or greater chance of
<br />flooding in any given year
<br />
<br />substantial improvement Any reconstruction,
<br />rehabilitation, addition, or other improvement of a
<br />structure, the cost of which equals or exceeds 50 percent of
<br />the market value of the structure before the "start of
<br />construction" of the improvement
<br />
<br />structure For floodplain management purposes, a walled
<br />and roofed building, including a storage tank for gas or
<br />liquid, that is principally above ground, as well as a
<br />manufactured home
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