Two states drive the broader trend of flood insurance policies in the Ninth District. Ironically, one of them is the smallest district state by population.
North Dakota ranks second among district states in the number of flood policies in force, but has easily the highest concentration of flood insurance policies on a per household basis (see Charts 1 and 2). The Red River Valley is responsible for a large share of flood insurance policies. The valley is home to two of the state’s largest cities (Fargo and Grand Forks) and more than half of the state’s flood insurance policies because of the valley’s exceptionally flat topography, which produces wide-reaching floods. Still, the state’s comparatively high number of flood insurance policies equals just 6 percent of all single-family structures (an artificially high rate because some policies in force also cover small business and other nonresidential structures).
North Dakota and Minnesota are responsible for the lion’s share of volatility in flood policies from 2010 to 2012 (see Chart A). Montana and South Dakota saw somewhat smaller changes in annual policies and have significantly fewer policies. Wisconsin has the largest number of flood insurance policies among district states—a function of the state’s larger population and large number of water bodies in that state. But it saw none of the volatility in policies in 2011 because the state experienced little of the flood threat seen in nearby states that year.