Managing floods in large river basins in the USA: The Sacramento River

Abstract

The Sacramento River was an important area for flood management, with involvement by the federal government back to the nineteenth century, starting with the same levees-only approach as initially used on the Mississippi, but evolving to the current system of flood bypasses implemented in the early twentieth century. After the 1986 and 1997 floods (and a 2003 court decision holding the state liable for damages from levee failures), the California legislature enacted a set of reforms in 2007 that included an enhanced flood protection standard for urban areas of theCentral Valley; maps showing 100- and 200-year floodplains; and programs to set back some levees and strengthen others. The National Flood Insurance Program approach is a poor fit for agricultural areas, and the state is exploring ways to modify its application to agricultural areas. Flood bypasses, crucially important infrastructure that also provide valued wildlife habitat, will be expanded to yield multiple benefits.