DeKalb County and Allen County in the U.S. will soon have latest flood maps. Both new maps will be digital maps that can be used in GIS, and are dynamic computerized maps that let users add and subtract layers at will, from aerial photographs to street addresses to underground drainage systems. The DeKalb County maps are nearly ready to be published, and will likely be unveiled for the public the second or third week in December. It will be almost a year, however, before the new Allen County maps are published and become official.
Under federal law, banks writing a mortgage have to determine whether the house is in a flood plain, and if so, the banks must require flood insurance. That requirement lasts for the life of the loan. That means every time a new flood map is published every loan is checked to see whether it covers a home in a flood plain. That process prompted hundreds of changes for Allen County residents in the last update and sparked hundreds of calls to officials from residents who suddenly had to buy flood insurance.