A P.C. peripheral canal

“PERIPHERAL CANAL” just might be the most fearsome phrase in California politics: two words that reignite decades-old water wars, pitting environmentalists and Northern Californians against farmers and Southern Californians, and destroying political careers in the process. Gov. Arnold Schwarzenegger is brave to bring up the idea anew, as he did this week. Californians should hear him out.

The Sacramento-San Joaquin Delta is an expanse of islands and levees that’s home to farmers, vacationers and a unique native ecosystem. It’s also a conduit for more than a third of Southern California’s water supply. Gov. Jerry Brown ran into crushing opposition in 1982 when he backed a peripheral canal that would carry water around the delta to users in Southern California. Those users saw it as an extension of the system that greened their cities. Northern Californians, environmentalists and others saw it as a water grab. It was defeated at the polls by a 3-2 margin.

Much has changed in the quarter of a century since. Hurricane Katrina’s spectacular floods demonstrated why protecting a state’s water supply from old levees might make a lot of sense. Environmentalists who opposed the peripheral canal assumed that leaving the delta “alone” (that is, as an engineered freshwater system, with State Water Project pumps operating at its southern flank) would be a good way to preserve its ecosystem. That has not proved true. Scientists now know that delta species thrive when salinity fluctuates, as it did for millions of years. New research suggests that a canal might help mimic natural fluctuations, especially as global warming raises sea levels. And the old North-South political battle lines have shifted. Water districts in Northern California now depend on the delta too.

A peripheral canal is not, and should not be, a fait accompli. To the extent that the governor’s speeches this week gave the impression that “conveyance,” as he calls it, is more than an option, Schwarzenegger has done the state a disservice. But to the extent that canal talk prompts the state to grapple with its long-term water infrastructure needs, the governor is to be commended. Californians should surrender old hysterias and give a considered delta solution -- perhaps one that incorporates a peripheral canal -- a chance to emerge.