Setback Levee

A setback levee is an example of political consensus embodied in the performance of a hybrid form—reflecting the value of design.

A typical levee has a simple slope on each side of a crest, but a setback levee adds a bench on the water side of the crest. This bench accomplishes several things; it increases the carrying capacity of the river channel, useful in water delivery; it increases the mass of the levee, useful in thwarting flooding; and the bench creates a larger riparian zone, useful in the construction of artificial habitat.

Taken as a whole, the form of the setback levee is the basis for an unlikely coalition of urban, agribusiness, flood control and environmental constituencies, all major interests and powerful political forces.