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GLOSSARY
<br />• Base Food Elevation (BFE) is the computed
<br />elevation to which floodwater is anticipated
<br />to rise during the one percent annual
<br />chance flood (the base flood). The BFE is the
<br />regulatory requirement for the elevation or the
<br />floodproofing of structures, both commercial and
<br />residential. The relationship between the BFE
<br />and a structure's existing elevation determines
<br />the flood insurance premium.
<br />• Coastal High Hazard Areas (CHHA) is the area
<br />of special flood hazard extending from offshore
<br />to the inland limit of a primary frontal dune
<br />along an open coast and any other area subject
<br />to high -velocity wave action from storms or
<br />seismic sources. The CHHA is identified as Zone
<br />Von Flood Insurance Rate Maps (FIRMs). Special
<br />floodplain management requirements apply
<br />in V Zones, including the requirement that all
<br />buildings be elevated on piles or columns.
<br />• Compensatory storage is that area that is
<br />required, for storage of floodwaters, to offset
<br />the impacts of buildings, fill, and impervious
<br />surfaces within the floodplain.
<br />• Flood Insurance Rate Map is a map on which
<br />the ioo-year (one percent annual chance)
<br />and the Soo -year (0.2 percent annual chance)
<br />floodplains, Base Flood Elevations (BFEs),
<br />and regulatory floodways are delineated to
<br />enable insurance agents to accurately rate
<br />flood insurance policies for home owners and
<br />business owners in communities participating in
<br />the National Flood Insurance Program.
<br />• Freeboard is a factor of safety, usually
<br />expressed in feet above a known flood level,
<br />for purposes of floodplain management, and
<br />usually expresses the height above the BFE at
<br />which insurable structures must be built.
<br />• Regulatory floodway means the channel of
<br />a river or other watercourse and the adjacent
<br />land areas that must be reserved in order to
<br />discharge the base flood without cumulatively
<br />increasing the water surface elevation more than
<br />a designated height. Communities must regulate
<br />development in these floodways to ensure
<br />that there are no increases in upstream flood
<br />elevations.
<br />• Special Flood Hazard Area is the area subject
<br />to inundation by a flood that has a one percent
<br />or greater chance of being equaled or exceeded
<br />during any given year. This type of flood is
<br />commonly referred to as the " ioo-year flood" or
<br />the "base flood".
<br />• Zero -rise (regulatory) floodways is a designated
<br />regulatory floodway where no increase in flood
<br />heights occurs during the base flood, even those
<br />increases that are negligible and do not change the
<br />BFE. In communities that use a zero -rise floodway,
<br />the Federal Emergency Management Agency
<br />floodway is generally enlarged to include almost the
<br />entire floodplain. Fill and other encroachments are
<br />not allowed in the zero -rise floodway.
<br />districts to prohibit new structures and fill in
<br />the SFHA. Additionally, in Calais, Vermont,
<br />the use of large lot sizes in the city's Upland
<br />Overlay District protects sensitive upland
<br />areas from the adverse effects of inappropri-
<br />ate or high -density development.
<br />Myrtle Beach, South Carolina
<br />Myrtle Beach uses its Coastal Protection (CP)
<br />overlay zone to control erosion, preserve and
<br />maintain a recreational beach, safeguard
<br />property, and promote public safety. The
<br />overlay prohibits seawalls and new structures
<br />in an area bound by the top of the primary
<br />frontal dune system adjacent to the Atlantic
<br />Ocean and marked landward by drawing a
<br />line parallel to the primary frontal dune line
<br />equivalent to 5o times the annual beach ero-
<br />sion rate (which exceeds the state standards
<br />by io times the erosion rate). The regulations
<br />apply to all oceanfront property, with slight
<br />exemptions given to two historic pier struc-
<br />tures located in the city limits. According to
<br />Allison Hardin, the city's planner and former
<br />floodplain manager, "in cases of reconstruc-
<br />tion, if retreat is not possible, it is intended
<br />that existing buildings may be replaced with-
<br />out exceeding the gross square footage of the
<br />existing building and without any portion of
<br />the footprint of the building located in the CP
<br />district being exceeded."
<br />TRANSFER OF DEVELOPMENT RIGHTS
<br />Transfer of development rights (TDR) is a
<br />land preservation tool wherein a property
<br />owner yields some or all of the right to de-
<br />velop or use his or her property in exchange
<br />for the right to develop or use another parcel
<br />of property more intensively. Communities
<br />with TDR programs designate sending
<br />areas (where development rights can be
<br />purchased) and receiving areas (where pur-
<br />chased development rights can be applied).
<br />Kent County, Delaware
<br />Kent County has had a TDR program, ad-
<br />ministered by its planning department,
<br />since 2005. Under the county's program,
<br />participants must record an irrevocable
<br />preservation easement to memorialize the
<br />separation of the development rights from
<br />the property. Property owners who have
<br />transferred development rights from their
<br />land may continue to use the land for any
<br />purpose or use permitted by right by their
<br />zoning district except residential subdivi-
<br />sion. While ownership of the land may be
<br />transferred, the residential development re-
<br />striction remains with the land in perpetuity.
<br />ENGINEERING CERTIFICATIONS
<br />Finally, some communities, such as DuPage
<br />County, Illinois; Greenville, South Carolina;
<br />and Arlington, Texas, require engineering
<br />certifications to insure adherence to sound
<br />floodplain management standards. Bill
<br />Brown of the City of Arlington describes the
<br />theory: "Requiring strong technical analysis
<br />and establishing technical performance
<br />standards goes a long way to facilitate
<br />development that is safer from flood risks,
<br />while avoiding the takings issues." As
<br />Brown explains, the city is not saying no, but
<br />by imposing this certification requirement,
<br />some projects that would otherwise proceed
<br />become financially impractical. "The tradi-
<br />tional method of zoning has limited liability
<br />at best," says Brown. "The strong technical
<br />analysis and performance standards that are
<br />signed by a licensed professional carry (per-
<br />sonal and professional) liability."
<br />THE TAKINGS ISSUE
<br />Obviously, there are many regulatory tools
<br />at the community's disposal to oversee
<br />development and promote flood resiliency.
<br />Sadly, many communities fail to adequately
<br />regulate through zoning or other regulatory
<br />mechanisms, in relation to flood prevention,
<br />for fear of the takings issue. Yet a failure to
<br />regulate may set a community up for com-
<br />mon law liability suits.
<br />According to a 2008 article by Edward
<br />A. Thomas and Sam Riley-Medlock in the
<br />Vermont -Journal of Environmental Law, there
<br />have only been a handful of successful chal-
<br />lenges to floodplain regulations as a taking.
<br />In those cases, a nearly complete prohibi-
<br />tion of building on the property was found to
<br />have occurred with no clearly demonstrated
<br />hazard -related benefit for the community.
<br />The Thomas-Medlock research concluded
<br />that the trend is for the courts to sustain
<br />government regulation of hazardous activi-
<br />ties for the prevention of harm.
<br />In communities that fail to adequately
<br />administer their own regulations, however,
<br />governments have been held liable for
<br />negligence or nuisances where the govern-
<br />ment has issued a development permit that
<br />increased flood heights, flood magnitudes,
<br />or flood intensity on other property. In re-
<br />search prepared for the Association of State
<br />Floodplain Managers (ASFPM) Foundation,
<br />Jon Kusler explained that courts have sup-
<br />ported regulations that exceed the NFIP
<br />standards, provided those regulations were
<br />enacted in furtherance of public safety and
<br />do not deny all use.
<br />ZONINGPRACTICE 4.12
<br />AMERICAN PLANNING ASSOCIATION [page 6
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