Using Multi-Objective Management to Reduce Flood Losses in Your

Rip rap: Large rocks placed along a bank or shoreline to protect it from erosion.
Riparian ecosystem: A distinct association of flora, fauna, and soil occurring
along a river, stream, or other body of water and dependent upon high water
tables and occasional flooding to maintain its viability. These areas often exhibit
high biological productivity and species diversity.
Riverine: Of or produced by a river. Riverine floodplains have readily
identifiable channels. Floodway maps can only be prepared for riverine
floodplains.
Sand dunes: Naturally occurring accumulations of sand that form ridges or
mounds landward of a beach.
SBA: U.S. Small Business Administration.
SCS: Soil Conservation Service, the old name for the U.S. Department of
Agriculture’s Natural Resources Conservation Service.
Sensitive area: An area defined by state or local regulations as deserving special
protection because of its unique natural features or its value as habitat for a wide
range of species of flora and fauna. A sensitive area is subject to more restrictive
development regulations than other floodplains or wetlands.
SFHA: Special Flood Hazard Area.
Sheet flow: A condition of flooding where there is moving water but no
identifiable channel. Flooding depths are usually shallow (less than 3 feet). Sheet
flow may have a high velocity, as on alluvial fans.
SHMO: State hazard mitigation officer, usually in the state emergency
management agency.
SHPO: State historic preservation officer in the state historic preservation
agency.
Special Flood Hazard Area (SFHA): The base floodplain delineated on a Flood
Insurance Rate Map. The SFHA is mapped as a Zone A (see definition). In
coastal situations, Zone V (see definition) is also a part of the SFHA. The SFHA
may or may not encompass all of a community’s flood problems.
Standard project flood: A very large, low-frequency flood used as the standard
for designing major flood control structures.
Structural measures: Flood control techniques that modify flood flows.
Examples are dams, reservoirs, levees, channel alterations, and diversions.
Surcharge: An increase in flood elevation due to an obstruction of the floodplain
that has reduced its conveyance capacity. Floodway boundaries are usually set
based on a specified surcharge that is allowed to be caused by new development in
the floodplain.
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