Unless specifically defined below, words or phrases used in these regulations shall be interpreted so as to give them the meaning they have in common usage and to give these regulations the most reasonable application.
Base Flood. The flood having a 1% chance of being equaled or exceeded in any given year. The base flood may also be referred to as the 1% chance annual flood or 100 year flood.
Base (100-Year) Flood Elevation (BFE). The water surface elevation of the base flood in relation to a specified datum, usually the National Geodetic Vertical Datum of 1929 or the North American Vertical Datum of 1988, and usually expressed in Feet Mean Sea Level (MSL). In Zone AO areas, the base flood elevation is the natural grade elevation plus the depth number (from one to three feet).
Executive Order 11988 (Floodplain Management). Issued by President Carter in 1977, this order requires that no federally assisted activities be conducted in or have the potential to affect identified special flood hazard areas, unless there is no practicable alternative.
Federal Emergency Management Agency (FEMA). The agency with the overall responsibility for administering the National Flood Insurance Program.
Fill. A deposit of earth material placed by artificial means.
Flood or Flooding. A general and temporary condition of partial or complete inundation of normally dry land areas from the overflow of inland or tidal waters, and/or the unusual and rapid accumulation or runoff of surface waters from any source.
Flood Insurance Rate Map (FIRM). An official map on which the Federal Emergency Management Agency or the U.S. Department of Housing and Urban Development has delineated the areas of special flood hazard.
Flood Insurance Risk Zones. The zone designations on FIRMs that indicate the magnitude of the flood hazard in specific areas of a community. Following are the zone definitions:
Zone A. Special flood hazard areas inundated by the 100-year flood; base flood elevations are not determined.
Zones A1-30 and Zone AE. Special flood hazard areas inundated by the 100-year flood; base flood elevations are determined.
Zone AO. Special flood hazard areas inundated by the 100-year flood; with flood depths of one to three feet (usually sheet flow on sloping terrain); average depths are determined.
Zone AH. Special flood hazard areas inundated by the 100-year flood; flood depths of one to three feet (usually areas of ponding); base flood elevations are determined.
Zone A99. Special flood hazard areas inundated by the 100-year flood to be protected from the 100-year flood by a federal flood protection system under construction; no base flood elevations are determined.
Zone B and Zone X (shaded). Areas of 500-year flood; areas subject to the 100-year flood with average depths of less than one foot or with contributing drainage area less than one square mile; and areas protected by levees from the base flood.
Zone C and Zone X (unshaded). Areas determined to be outside the 500-year floodplain.
Flood Insurance Study (FIS). The official report in which the Federal Emergency Management Agency or the U.S. Department of Housing and Urban Development has provided flood profiles, floodway boundaries (sometimes shown on Flood Boundary and Floodway Maps), and the water surface elevations of the base flood.
Flood Protection Elevation. The Flood Protection Elevation, or FPE, which is the base flood elevation plus one foot of freeboard. In areas where no base flood elevations exist from any authoritative source, the flood protection elevation can be historical flood elevations, or base flood elevations determined and/or approved by the floodplain administrator.
Floodway. A channel of a river or other watercourse and the adjacent land areas that have been reserved in order to pass the base flood discharge. A floodway is typically determined through a hydraulic and hydrologic engineering analysis such that the cumulative increase in the water surface elevation of the base flood discharge is no more than a designated height. In no case shall the designated height be more than one foot at any point within the community. The floodway is an extremely hazardous area and is usually characterized by any of the following: Moderate to high velocity flood waters, high potential for debris and projectile impacts, and moderate to high erosion forces.
Freeboard. A factor of safety usually expressed in feet above a flood level for the purposes of floodplain management. Freeboard tends to compensate for the many unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood and floodway conditions, such as wave action, obstructed bridge openings, debris and ice jams, and the hydrologic effect of urbanization in a watershed.
Hydrologic and Hydraulic Engineering Analysis. An analysis performed by a professional engineer, registered in the State of Ohio, in accordance with standard engineering practices as accepted by FEMA, used to determine flood elevations and/or floodway boundaries.
Letter of Map Change (LOMC). An official FEMA determination, by letter, to amend or revise effective Flood Insurance Rate Maps, Flood Boundary and Floodway Maps, and Flood Insurance Studies. LOMC’s are broken down into the following categories:
Letter of Map Amendment (LOMA). A revision based on technical data showing that a property was incorrectly included in a designated special flood hazard area. A LOMA amends the current effective Flood Insurance Rate Map and establishes that a specific property is not located in a special flood hazard area.
Letter of Map Revision (LOMR). A revision based on technical data that, usually due to manmade changes, shows changes to flood zones, flood elevations, floodplain and floodway delineations, and planimetric features. One common type of LOMR, a LOMR-F, is a determination concerning whether a structure or parcel has been elevated by fill above the base flood elevation and is, therefore, excluded from the special flood hazard area.
Conditional Letter of Map Revision (CLOMR). A formal review and comment by FEMA as to whether a proposed project complies with the minimum National Flood Insurance Program floodplain management criteria. A CLOMR does not amend or revise effective Flood Insurance Rate Maps, Flood Boundary and Floodway Maps, or Flood Insurance Studies.
Lowest Floor. The lowest floor of the lowest enclosed area (including basement) of a structure. This definition excludes an "enclosure below the lowest floor" which is an unfinished or flood resistant enclosure usable solely for parking of vehicles, building access or storage, in an area other than a basement area, provided that such enclosure is built in accordance with the applicable design requirements specified in these regulations for enclosures below the lowest floor.
National Flood Insurance Program (NFIP). The NFIP is a federal program enabling property owners in participating communities to purchase insurance protection against losses from flooding. This insurance is designed to provide an insurance alternative to disaster assistance to meet the escalating costs of repairing damage to buildings and their contents caused by floods. Participation in the NFIP is based on an agreement between local communities and the federal government that states if a community will adopt and enforce floodplain management regulations to reduce future flood risks to all development in special flood hazard areas, the federal government will make flood insurance available within the community as a financial protection against flood loss.
New Construction. Structures for which the "start of construction" commenced on or after the initial effective date of the City of Sidney Flood Insurance Rate Map, November 17, 1982, and includes any subsequent improvements to such structures.
Special Flood Hazard Area, or Areas of Special Flood Hazard. The land in the floodplain is subject to a 1% or greater chance of flooding in any given year. Special flood hazard areas are designated by the Federal Emergency Management Agency on Flood Insurance Rate Maps, Flood Insurance Studies, Flood Boundary and Floodway Maps and Flood Hazard Boundary Maps as Zones A, AE, AH, AO, A1-30, and A99. Special flood hazard areas may also refer to areas that are flood prone and designated from other federal, state or local sources of including but not limited to historical flood information reflecting high watermarks, previous flood inundation areas, and flood prone soils associated with a watercourse.
(Ord. A-3075. Passed 1-24-22.)