Thursday, Sept. 20, 2007 | ON THE SACRAMENTO-SAN JOAQUIN RIVER DELTA — Two men in a fishing boat slide through the glassy, slate-green water here, throwing hopeful casts in search of trophy bass.
Jeffrey Mount, a tan, energetic geology professor from University of California, Davis, gestures at the fishermen, who are trolling around the grassy remains of an earthen levee that collapsed more than 70 years ago. More than 140 levees have crumbled in the last century and flooded thousands of acres, Mount says, and more will continue breaking and causing devastating floods.
“All signs point to that as the future of the delta,” the professor says, from the deck of a touring catamaran. “It’ll be a good place to have a boat.”
The Sacramento-San Joaquin River Delta sits 450 miles north of San Diego — far enough away that it can seem like little more than a notion, a foreign place. But the delta’s 738,000 acres of crops, riverfront housing and heron-lined waterways are very real and vitally important to San Diego’s drinking water supply.
When the winter snows blanketing the Sierra Nevada melt, the runoff cascades into rivers that flow west toward San Francisco Bay, beneath the Golden Gate and out to the Pacific Ocean. If that snowmelt were a train, the delta would be its tracks.
But the delta, which is one-fourth the size of San Diego County, is under duress. Both its ecosystem and its infrastructure hover on the brink of collapse, from the smallest fish to the largest levee. A 6.5-magnitude earthquake would be strong enough to rattle miles of soft, earthen levees — little more than unstable mounds of peat — into a substance the consistency of toothpaste.