BOX 3-10

Past federal top-down approaches to manage flood risk typically promoted structural measures like levees or dams. Furthermore, prior to passage of the 1986 Water Resources Development Act and a new set of cost-sharing criteria, structural projects built by the Corps were 100 percent federally funded, which made them a favored solution for communities. The Corps approach to managing flood risks was developed by a cadre of Corps engineers trained in hydrology and hydraulics in the early twentieth century. The Corps processes estimating flood control project benefits, such benefit-cost analysis, and estimates of “damages prevented,” were designed around civil works structures.

Starting in the late 1960s, some communities began questioning the strong reliance on structural solutions to flood risks. Questions were raised about the Corps’ apparent inability under federal rules and procedures to identify viable nonstructural alternatives in its flood damage reduction studies. A committee of the National Research Council considered these issues and concluded that “the benefits of flood damages avoided should be explicitly accounted for in calculating project benefits” and recommended further study to determine if systematic biases existed against nonstructural solutions (NRC, 1999).

The city of Napa, California actually had to get congressional authorization for a combined solution, with a setback levee, purchase and restoration of upstream wetlands to store floodwater to lower flood levels, Department of Transportation funding to funding to raise bridges that were blocking flow, and FEMA mitigation buyout grants for some buyouts.

Grand Forks, North Dakota used FEMA buyout grants to buy out structures within a few blocks of the river, then grants from the Housing and Urban Development Authority (HUD) money to buy out a few more houses to make room for a much smaller levee way back from the river, leaving the buyout land for a recreational park that is used for camping but not permanent structures that could be damaged in floods.

Davenport, Iowa, is the largest city along the Mississippi River without a flood control levee. The city decided that it did not want a levee that would wall the city off from the Mississippi River and its aesthetic, historical, and cultural values. Over the years, the city has bought out structures to create parks and open space, limiting development in order to limit possible flood losses.

Today, Cedar Rapids, Iowa, is in the process of recovering from a disastrous 2008 flood of the Cedar River that inflicted considerable damage on structures in the floodplain. The city is working with the Corps of Engineers and is implementing a plan that includes a combination of structural works for higher-value property (some of which has been/is being constructed with private funds), relocations, and changed zoning regulations in vulnerable floodplain areas.

Nonstructural and less traditional approaches to flood risk management often present very complex administrative, real estate, financing, and social and cultural challenges. Satis-

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