More unreason about water in California

John Gibler in Solve Climate News via Earth Island Journal: The Sacramento-San Joaquin Delta used to be the region where the Sacramento and San Joaquin Rivers would meet, pool for hundreds of square miles, and slowly drain into the San Francisco Bay and out to sea through the Golden Gate. Not anymore. The San Joaquin River is mostly diverted for irrigation before it can reach the Delta and the Sacramento is largely lifted out of the southern tip of the Delta and pumped down the San Joaquin Valley for irrigation.

Today, the Delta is a work of human engineering built over 150 years that consists of thousands of miles of levees, emaciated river flows, immense pumps, bromide and mercury contamination, endangered species, and below sea level “islands” housing communities and farms that would most likely be under water within hours of a major earthquake.

The Delta is the hub of California’s water engineering system and the current focal point of the state’s infamous water wars. Environmentalists and Delta communities want to reduce water exports. Irrigators in the San Joaquin and their strange bedfellows in the powerful Metropolitan Water District of Southern California, which draws water pumped through the Delta, want to increase water exports. There is one thing all sides agree on: The Delta is a disaster waiting to explode.

…“We have a system where we try to deliver more water than can be reliably delivered. All the signals tell us that we have been exceeding the capacities of the system,” said Tina Swanson, executive director and chief scientist at the Bay Institute. “It is incontrovertible that we have to expect to export less water from the Delta than we have in the past; it is unsustainable. We’re going to have to learn to make do with less.”…

The Suisun Marsh Salinity Control Gates span the Montezuma Slough at the Roaring River intake detail. They operate like a heart valve, allowing flow in only one direction. In this picture, the three gates are open to allow the freshwater ebb tide from the Sacramento-San Joaquin Delta to push the more saline Grizzly Bay water out of the slough. Photo by the Army Corps of Engineers