Floodplains & Flood Insurance
The goal of the floodplain ordinance is to minimize the threat to life and property resulting from flooding. This is accomplished by encouraging communities to preserve floodplains for carrying and storing flood waters.
Structures may continue to be located in floodplains. Structures to be located in the floodplain must not only be elevated above the 100-year flood elevation, but they must be placed so as not to diminish the ability of the floodplain to carry and store flood water. Therefore, the decision to buy an existing residence or build a new residence in the floodplain must be approached with great care.
Floodplains are lowland areas adjacent to lakes, wetlands, and rivers that are covered by water during a flood. The regulatory floodplain is the area covered by a flood that has a 1% chance of occurring in any given year, often referred to as the 100-year flood.
There are two components of the floodplain; floodway and flood fringe.
The floodway is the river channel and the areas immediately adjacent to the channel which are needed to pass the flow of the 100-year flood or 1% chance flood. The floodway is the area that experiences the deepest water and the highest flow velocities. Most Structures are not allowed within this district (including principal or accessory structures for residential, commercial or industrial purposes) due to the increased flood damage potential. Those uses that are allowed, such as fill or accessory structures for open space uses, require special attention prior to being proposed to ensure that the proposed use will not cause an increase to the 100-year flood elevation by encroachment.
The flood fringe is the part of the floodplain outside of the floodway. The flood fringe is primarily a flood water storage area, so fill and elevated structures can be placed in this area. Depths and velocities of floodwater in flood fringe areas are generally lower than in the floodway. Most development activities are allowed in the flood fringe as long as structures are elevated above the regulatory flood protection elevation and if it can be demonstrated through a hydraulic study that the fill will not increase or change the floodplain boundaries.