If not this California delta plan, then what?

If not this California delta plan, then what?
Competingfactions in California's water struggle have rejected virtually every comprehensive solution to preserving the delta, resulting in adegrading environment and a threatened water supply. (Randall Benton / MCT)

In years of average rainfall, when pumps at the south end of the Sacramento-San Joaquin River Delta lift water to two parallel aqueducts to begin the journey to Central Valley fields and Southern California households, the suction reverses the flow of the San Joaquin River, one of the state's two main freshwater arteries.

Instead of moving north and west to a series of bays and finally through the Golden Gate to the Pacific, the water is drawn backward, south toward the pumps, taking with it the young salmon and other migratory fish that need to reach the ocean to survive. Many are ground up in the pumps or are drawn near protective screens, where they are easy and predictable prey for invasive species.

To give a fighting chance to the surviving fish — and, by the way, to the entire ecological web of the Sierra, the Central Valley, the delta and the Pacific, not to mention the struggling but still existent California salmon industry — tanker trucks pull up near the pumps, where the fish are loaded, driven farther downstream and released, stunned and beaten by their ordeal.

Meanwhile, rising sea levels, failing levees and drought threaten the delta with intruding saltwater, potentially leaving the pumps nothing to send south but useless brack.

Some of the engineers and thinkers who mapped out the State Water Project in the mid-20th century predicted these problems (although perhaps not the absurdities, like the fish trucking) and had a solution: Divert the water farther north, from the Sacramento River. Fresh water would flow to the canals naturally, by gravity, with no new pumps to reverse the flow and block the fish migration, and no chance of saltwater intruding that far north and tainting the supply for farms and families.

The south pumps would still operate when necessary, with the entire system being managed by experts who could toggle between the two intakes as the seasons and circumstances dictate. The project would be paired with a long-range plan to mitigate environmental damage from more than a century of replumbing the delta.

Simple, right?

Hardly. Factions in California's water struggle each despise the destructive status quo but reject virtually every comprehensive solution in the belief that some other interest stands to gain at their expense. That belief, sad to say, is sometimes spot-on. The result is a rapidly degrading environment, a threatened water supply and an angry stasis that resembles nothing so much as the Middle East peace process.

The latest effort — the Bay Delta Conservation Plan — began in 2009, but today, in the midst of a historic drought, mistrust and recriminations have threatened its demise, especially the component that proposes a Sacramento River intake and tunnels leading south to the aqueducts. Even the plan's ostensible supporters sometimes seem to hate it — that is, when they focus on how much they'd have to pay for it. Delta interests, meanwhile, reject the whole proposal as a “water grab.”

The administration of Gov. Jerry Brown, despite many iterations of the proposal and despite much number-crunching and diplomacy among the factions, has been unable to produce a plan that could qualify for long-term environmental permits while still producing enough water to entice the large water agencies to finance the project upfront.

Last week Brown offered a scaled-back version that relies on traditional year-to-year environmental permitting rather than the half-century-long permit that would have given water agencies some assurance of supply. Agencies would pay over time as they take their water — but they're still not ready to sign on.

Delta interests, which complained before about losing farm acreage to environmental restoration (although they claimed they were only fighting against losing land to the tunnels), now complain that slashing those plans leaves their delicate land unprotected. Some contractors appear less interested in the tunnels and are banking instead on increasing their supplies through aggressive rollbacks of environmental safeguards in Congress.

So if this latest delta plan fails, then what? How do environmentalists propose to decrease the reverse flow that destroys the fish and California's fishing industry with it? How do delta farmers plan to protect their crops, livelihoods and homes against rising sea levels and vulnerable levees? How do water contractors expect to sell saltwater to farms and families? How do we stave off the environmental collapse of the state's heart and lungs? The factions that keep rejecting delta plans, or else damning them with faint praise, owe California some workable alternatives that address all of the state's needs, not just their own.

Any viable plan must include two interrelated ingredients: science-based management of the delta, with biologists and hydrologists rather than water contractors or politicians deciding how much water is needed to preserve species; and increased trust among the factions. But trust has been severely damaged by continuing efforts in Washington to craft legislation to diminish the role of science in managing flows and by politicians who laughably claim, in this fourth year of drought, that the San Joaquin Valley's lack of water is a man-made condition.

Fighting back against extinctions and the collapse of the largest estuary on the west coast of both American continents goes hand in hand with California's leadership in the battle against global climate change, but with this distinction: Although the state gains nothing directly (except merit) by reducing carbon emissions, protecting an ecosystem that extends from the mountains to the ocean also just happens to protect the water supply by safeguarding against saltwater intrusion despite environmental cataclysm. If the Bay Delta Conservation Plan doesn't still offer the best chance of accomplishing those goals, we have yet to see the better proposal.

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