A Peripheral Canal has been proposed to divert water from the Sacramento River, through (or around the periphery of) the San Joaquin-Sacramento River Delta. It would transfer water into the California Aqueduct, North Bay Aqueduct, South Bay Aqueduct, and San Luis Canal via the Jones and Banks pumping stations, then be pumped to Central and Southern California (including San Francisco Bay Area water providers, like Santa Clara Valley Water District). Construction costs are estimated at between $3 and $17 billion, depending on the source. A 2006 report[1] prepared by Washington Group International for the State Water Contractors (e.g. Metropolitan Water District) estimates the cost of a canal along the eastern side of the Delta to be between $3.3 and $3.7 Billion.
Currently, that water is being pulled through the San Joaquin-Sacramento River Delta. The through-Delta system has turned the Delta, originally a fluctuating-salinity estuary, into a freshwater basin. It has also created unnatural north to south flows in the Delta, confusing native species such as the Delta Smelt and disturbing the ecosystem.
Voters defeated a ballot initiative to build the Canal in 1982. Ever since then, the words "Peripheral Canal" have been called the "third rail" in water politics.
In recent years, however, after Judge Wanger shut off pumping stations in the South Delta because of their environmental impact, the idea of a Peripheral Canal has had a revival. Among others, Tom Birmingham, the head of the Westlands Water District, Tim Quinn, the director of the Association of California Water Agencies, [2]and Governor Arnold Schwarzenegger's Blue Ribbon Delta Vision Panel[3] have fallen in line with the idea, although the Delta Vision Panel did not rate it as its primary goal.