Much of the water supplied to Southern California is provided by the State Water Project, which collects water at the south end of the Sacramento/San Joaquin Delta.
The Delta is extremely fragile, both geologically and environmentally. The Delta consists of over 50 islands, many of which are subsiding due to intense, decades-long farming of the peat soils that make up the region. To prevent flooding, local farmers have dredged silt from the river bottoms to construct levees. Unfortunately, the area is part of the Hayward Fault Zone, which is capable of producing a 6.5 earthquake. A quake of that magnitude could demolish many of the poorly-constructed levees. Should that occur, the islands would be flooded with salt water from San Francisco Bay, rendering Water Project pumps at the Delta’s south end useless.
Proposals to bypass this fragile zone by building tunnels or aqueducts that would siphon water from farther north are under consideration. Northern Californians fear water thievery by the south. Delta farmers fear a land grab. Tax and ratepayers fear another costly boondoggle. Obviously, these remedies would be expensive. A water bond dealing with some of these issues may be on the 2014 ballot and ratepayers would have to foot the bill for aqueducts or tunnels