Buildings may topple and lives may be lost if the Big One shakes the wrong part of California but another catastrophic consequence of an enormous earthquake in the San Francisco area may involve water. Two thirds of the state's drinking water supply flows through the gigantic Sacramento-San Joaquin River Delta region east of San Francisco Bay -- and the levees that help direct the massive amounts of water south to farmlands and cities are so antiquated that many may simply collapse with a major temblor. The resulting flooding could also put California's huge farm belt, hundreds of thousands of businesses and millions of residents at enormous risk.

Everyone has known of that doomsday scenario for years -- a time in which the needs of farmers, the ambitions of environmentalists and the thirst of cities clashed. The big news this week is that California finally passed legislation to overhaul the state's aging water system. Governor Arnold Schwarzenegger called it "an historic agreement" and promised to sign into law. "Water is the lifeblood of everything we do in California," Schwarzenegger said. "Without clean reliable water, we cannot build, we cannot farm, we cannot grow, we cannot prosper."

The legislation proposes billions to repair and protect the largest estuary on the West Coast. The twin goals of the legislation are a massive restoration of the Delta's ecosystem, a project akin to saving the Everglades in Florida, and a new modern conveyance system to move water through the Delta and around the state with conservation and efficiency. It is an intricate one as well because the giant pumps that speed water to state and federal aqueducts have played a part in bringing the Delta to the verge of ecological collapse in the first place.