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d) occasional small beaches for boat landing and swimming. e) Passageway and salinity gradient for anadromous fish on spawning runs. f) Fish and wildlife habitat, especially in riparian growth. g) A scenic reserve for nature study and relaxa- tion, a predominantly open space experience. 2. The Levees : Levees have been constructed to provide flood pro- tection. However, the levees vary in quality. Privately maintained levees generally were not built on a sound foundation nor properly maintained over the years. Frequently, the levees were constructed from peat which is low in density, low in shear strength, and high in moisture content. when wet, it loses any resistance to movement and thus capable of failing. Levee failures, as well as overtopping of levees are not uncommon. Sufficient bulk at the base of the levee, in combination with the poor fill material, has contributed to failure and flooding of Delta islands. Subsidence will occur in peat filled levees. These levees will require periodic fill to maintain the levee above flood heights. The levee may also weaken through erosion from flood flows, tidal flows, and wavewash from wind and boats. The California Department of Water Resources (DWR) has developed a plan for improvement of the Delta levees following the flooding of Brennan and Andrus Islands. Under this program, islands with extensive agriculture would be protected from 50 year flood levels. Improvement of these levees would include raising the levee 15 feet above the 50-year flood line, decreasing the slope to at least 2 :1, applying rock rip rap and suitable vegetation, and, where necessary, building a landside berm to support the levee as a counterweight for high water flows. DWR has determined that a portion of the Roberts Island levee along Turner Cut will require improvement (See Map 1A) . 3 -