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10 MEANDER BELTS A considerable amount of development has occurred in the floodplains of California's major rivers. Much of that development, such as urbanized south- western Los Angeles County, cannot be undone to let rivers run their natural courses. But are there strategies that can provide needed flood protection and yet restore some of the environmental benefits of free-flowing rivers? One such strategy is the meander belt, a segment where the river can be allowed to follow its natural course without extensive levees. Snakelike meander belts help reduce flow velocities in rivers and create the aquatic habitat that supports fish such as salmon and trout. A typical meander bend causes a steep cut on the outer river bank. Here, overhanging vegetation shades pools that are important holding habitat for salmon and trout. Just downstream of the cut bank, gravel riffles typically occur that provide habitat for the invertebrates upon which the fish feed, A series of meander bends creates a meander belt of point bars and other features that support the riparian vegetation and wildlife that once lined the banks of California's rivers. Meander belts also can improve flood control by slowing flow velocities and allowing floodplains to act as pressure-relief valves during floods. Overbank STREAM FLOWS Another restoration strategy for rivers is to manage stream flows (though not necessarily velocity) in ways that more closely match natural flow patterns. Most California rivers historically had wide seasonal flow variations, and many plant and animal species were adapted to these patterns. Human activities such as hydraulic mining, water diversions and dam construction altered the seasonal flow patterns of those water courses, For instance, before construction of Shasta Dam, peak flows on the Sacramento River usually occurred in February and March, and the lowest flows occurred between July and October. Since Shasta Dam came on line in 1944, those flows (measured at Red Bluff) have been evened out over the year, although aggregate annual flows are similar to those before the dam was flooding in meander belts also helps remove suspended sediment and pollutants from the water column. The most visible experiments with meander belts have occurred on the Cosumnes and Sacra- mento rivers. Along stretches of both rivers, riparian forests have begun to re-establish themselves, followed quickly by native birds such as Swainson's hawk (listed as threatened under the state ESA) and the Western yellow-billed cuckoo (listed as endangered under the state ESA). J Creating a meander belt is not easy. Land owners who live near levees often fear that levee removal will make their property more vulnerable to flooding. Proponents of meander belts have had to use a variety of techniques to get buy-in from land owners along proposed meander belts such as outright land purchases, easements, or other legal agreements. Along a 200-mile stretch of the Sacramento River between Red Bluff and Colusa, government agencies and private groups have used land purchases to restore some of the riparian habitat of cottonwoods, willows, and sycamores that once bordered the river. During the first seven years of its ERP, CALFED plans to initiate meander belts on at least three to five tributary rivers. Its long-term "vision" is to restore healthy, meandering alluvial rivers that support self- sustaining populations of plants and animals, built. The changes in flow patterns are believed to have affected some plant and animal species that were adapted to the seasonal flow variations. CALFED's ERP calls for a variety of actions that together are designed to more closely resemble the natural flow regimes of rivers that feed into the Delta, CALFED is considering minimum stream flow targets for dry, normal and wet years for the Sacramento and San Joaquin River systems between March and May, And CALF ED proposes to periodically limit water diversions in the fall and winter to increase freshwater flows through the Delta, CALFED planners believe these steps would improve natural sediment transport, stimulate the estuary foodweb, and provide adequafe flows to meef the needs 01 a variety of fish,