PD Editorial: A single tunnel might make sense for California

Gov. Jerry Brown’s plan to drill two enormous tunnels to divert water to the Central Valley and Southern California should have been buried a long time ago.

The $17 billion price is too high, as is the risk of an out-and-out water grab at the expense of the Sacramento-San Joaquin Delta, the largest estuary on the West Coast.

But the governor stubbornly resisted alternatives to his California WaterFix - until now.

A memo posted last week on a state website for contractors said the Brown administration is considering a single tunnel, with a second one postponed until an unspecified date in the future.

That would be a huge concession, and, depending on the particulars of a scaled-down project, it could point toward a truce in California’s water wars.

It’s too bad that this opening didn’t come sooner, as Brown has less than a year left in office to broker a deal to protect the delta and West Coast fisheries while providing more reliability for Southern California cities and Central Valley growers.

Fortunately, water experts at the Public Policy Institute of California completed some of the groundwork in 2016.

Moreover, some leading opponents of the twin tunnels project are open to a single tunnel. So is the giant Metropolitan Water District of Southern California, the only major water agency to commit funding for Brown’s original plan.

“I’m hopeful this will be seen as a kinder, gentler, more agreeable approach,” MWD General Manager Jeffrey Nightlinger told the Bay Area News Group.

For MWD and other big contractors, replumbing the delta is all about securing their water supplies. That doesn’t deserve a higher priority than restoring the badly degraded delta and enacting enforceable rules to protect it in the future.

But if nothing gets done, conditions in the delta will only get worse, and water supplies for the south will continue to be disrupted. So each side has an incentive to bargain.

The delta, like the Central Valley, is home to a thriving agriculture industry. It’s also the source of drinking water for millions of Bay Area residents (and millions more in Southern California), and it supports one of the largest salmon fisheries on the West Coast.

Its health is undermined by the giant pumps near Tracy that suck water from the delta into southbound canals. The pumps chew up fish and reverse river flows, disrupting salmon migration and allowing saltwater to flow into the delta. When the pumps get shut down, often in response to court orders enforcing environmental laws, water deliveries are disrupted.

Brown’s WaterFix would replace the pumps and move the diversion upstream.

It’s a promising approach, but two tunnels was never a workable solution. Supporters insist that two are required to facilitate diversion of large storm water surpluses and to ensure that deliveries aren’t halted by maintenance needs or other exigencies.

But two tunnels also make it possible for the state to open the spigot and send substantially more water south, making conditions in the delta exponentially worse.

California history illustrated why that would be an unacceptable risk for any concerned with the delta - and why it won’t be easy to craft an agreement that satisfies the longtime antagonists in the water wars.

But a water fix is desperately needed, and a single tunnel is worth exploring. Let’s hope the Brown administration didn’t wait too long to float this compromise.