Floodplain Regulations and the National Flood Insurance Program
The National Flood Insurance Act of 1968 allows the Federal Insurance and Mitigation Administration (FIMA) to make flood insurance available only to communities that have adopted flood damage prevention regulations. Without community oversight of building activities in the floodplains, existing buildings and developments in the floodplain could be further undermined by the careless building of other buildings and developments. Unless the community as a whole practices adequate flood hazard mitigation, the potential flood loses will not be reduced sufficiently to affect disaster relief costs. Insurance costs would likely rise reflecting the probable higher flood loses that would result without the enforcement of flood damage prevention regulations.
Lancaster City Council adopted floodplain regulations with passage of the Flood Damage Prevention Ordinance, Chapter 1331 of the Codified Ordinances of the City of Lancaster, Ohio, in 1979 that became effective in 1980. The ordinance was revised in 2011 as part of the Flood Map Modernization program.
Under Chapter 1331, City Council has established the Certified Building Department as the Administrator of the floodplain regulations. They are responsible for all aspects of the Development Permit Process and for maintaining the required National Flood Insurance Program information.
The 100-year flood now referred to as the 1% flood-meaning it has a 1% chance of occurring in any year, has become the accepted national standard for regulatory purposes. It is defined as the flood event that has a one percent chance of occurring in any given year or, on the average, occurs once in a 100-year period. This does not mean that if there is such a flood this year it will not happen again for another 100 years. There have been cases in
Floodplain regulations are designed to guide floodplain development to lessen the damaging effects of floods. Floodplain regulations for the city of
For regulatory purposes, the floodplain is divided into two areas based on water velocity: the floodway and the flood fringe. The floodway includes the channel and adjacent floodplain area that is required to pass the 100-year flood without unduly increasing flood heights. This is the hazardous portion of the floodplain where the fastest flow of water occurs. Due to the high degree of hazard found in the floodway, floodplain regulations require that proposed floodway developments do not block the free flow of flood water as this could dangerously increase the water's depth and velocity. The flood fringe is the portion of the floodplain, outside of the floodway, that contains slow-moving or standing water. Development in the fringe will not normally interfere with the flow of water. Therefore, floodplain regulations for the flood fringe allow development to occur but require protection from flood waters through the elevation of buildings above the 100-year flood level or floodproofing buildings so that flood water cannot enter the structure.