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Huge weirs along the Sacramento River allow for planned flooding in bypass areas, thus helping protect communities downstream.

for levee failures. Rivers could be allowed to overflow onto farmland and open space in order to protect urbanized areas downstream. Indeed, that is exactly what happens today when the Sacramento River overflows into the Sutter and Yolo bypass areas west and north of the state's capital city. It's analogous to using "circuit breakers" to keep a house from

burning down when an electrical circuit fails. As Professor Mount has said, "The way to reduce flooding in one area is to promote flooding in others. That's the way rivers do it and we should follow their lead."

Working with rivers

"There is almost a perfect overlap between the measures needed for implementing an effective flood management strategy and those needed for meaningful restoration of the valley’s fish and wildlife.

Dr. Philip Williams, Hydrology and flood management expert

Working with rivers and floods rather than against them creates opportunities for improved flood management and reduced damage costs, higher water quality, healthier ecosystems, and more cost effective investments of taxpayer dollars.

Before the advent of modern construction techniques and materials, people adapted to the periodic flooding of the Central Valley by limiting their investments in flood-prone lands or making sure their investments were on high ground and out of harm's way.

"When we talk about construction now it’s not necessarily concrete. It’s restoring rivers, putting a meander in, landscaping and revegetation. "

Walter Yep, U.S. Army Corps of Engineers

Along with the ingenuity of bypass channels along the Sacramento River, more than a 100 years ago Sacramentans essentially flood-proofed their homes by building their first floors one story above the ground. In fact, the city of Sacramento literally raised the ground level of town by about 12 feet in order to escape frequent flooding." In contrast, the San Joaquin River's tiny flood conveyance capacity was overwhelmed in 1997 because of modern era assumptions involving concrete and construction. Poorly situated floodplain communities were surprised when river levees overtopped or broke; it had been long assumed that upstream reservoirs and dams could contain all floods.

However, the failure of flood control to fully contain floods still represents an historic opportunity to embrace a flood management effort that provides greater reliability, greater hazard reductions and, in the long run, lower costs than simply

continuing with the present system. As San Francisco-based hydrology expert Dr. Philip Williams has argued, "a solution which fully integrates flood management and river/watershed restoration would also help increase wetland habitat for waterfowl and fish, the very species that have been largely destroyed by the structures and operations of our traditional flood control system."'

Providing more floodplain storage space, more floodway space, and even trying to reduce flood damages by designing flood system "circuit breakers" could help localize problems within an overall system and preserve key urban

Continued in Beyond Flood Control Part III

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Nearly 85 percent of the Sacramento River overflows into the bypass areas like this one in Yolo County during flood events, thus helping protect California’s capitol city from flooding.

Inside