California Code, Water Code - WAT § 12311

(a) The department shall develop and implement a program of flood control projects on Bethel, Bradford, Holland, Hotchkiss, Jersey, Sherman, Twitchell, and Webb Islands, and at other locations in the delta and for the Towns of Thornton and Walnut Grove, and for approximately 12 miles of levees on islands bordering Northern Suisun Bay from Van Sickle Island westerly to Montezuma Slough.  This program shall have, as its primary purpose, the protection of discrete and identifiable public benefits, including the protection of public highways and roads, utility lines and conduits, and other public facilities, and the protection of urbanized areas, water quality, recreation, navigation, and fish and wildlife habitats, and other public benefits.  The program shall also include net long-term habitat improvement.

(b) Notwithstanding subdivision (a), the department shall develop and recommend a plan of action, including alternatives, for flood control for the Towns of Thornton and Walnut Grove and shall submit the plan to the Legislature by January 1, 1989.  The department shall not allocate any funds for implementation of the plan of action for flood control for the Towns of Thornton and Walnut Grove until a plan is approved by the Legislature.