California's water situation is bleak

Robert F. Service in Science Insider: If California hopes to prevent further extinctions of native species of endangered fish, the state should abandon efforts to take desperate measures to save individual species under the Endangered Species Act (ESA) and instead look to bolster entire aquatic ecosystems. That's among a long list of recommendations in a new book that was released last night from the Public Policy Institute of California (PPIC). It was written by a team of scientists, engineers, economists, and legal experts from three University of California (UC) campuses and Stanford University.

"Our assessment of the current water situation [in California] is bleak," says Ellen Hanak, a PPIC economist, who co-authored the study. "California has essentially run out of cheap, new water sources," Hanak says. Water quality is deteriorating. Pollution from agricultural runoff and other "non-point" sources is increasing. And efforts to manage water and species recovery are fragmented, with hundreds of local and regional agencies responsible for water supply, water treatment, flood control, and land-use decisions. The upshot is that, despite decades of actions to save aquatic species under the ESA, the trend has been relentlessly downward. Seven of the state’s 129 native fish species are already extinct. Since 1989, the number of native fish species listed as threatened or endangered has more than doubled to 31. And over that same period, the number of species that were “reasonably secure” has dropped from 44% in 1989 to 38% in 1995 and 22% in 2010.

Even worse crises are looming. Most threatening is the vulnerability of the hub of the state’s fresh water system, the Sacramento-San Joaquin delta, which drains water from the northern Sierra mountains. Massive pumps in the southern end of the delta suck nearly 10 billion cubic meters of water per year from the delta and send it to farmers in the Central Valley and urban residents in Southern California. Over the past century, farmers have built a network of more than 1700 kilometers of levees to protect farmland in the delta from floodwaters. Those levees, most of which are simple earthen berms, are weak and vulnerable to earthquakes, seasonal floods, and rising waters expected as a result of climate change. The failure of even a fraction of the levees would draw massive amounts of saltwater in from San Francisco Bay, forcing the state to shut off the pumps, cutting off water supplies for many months, and costing the state’s economy billions of dollars, the report says. Risks from droughts, floods, climate change, and declining habitat for fish are also rising over time.

“Today’s system of water management, developed in previous times for past conditions, is leading the state down a path of environmental and economic deterioration. We’re waiting for the next drought, flood, or lawsuit to bring catastrophe,” Hanak says…

This photo was published opposite page 209 of "California Highways: A Descriptive Record of Road Development by the State and Such Counties as Have Paved Highways", 1920, written by Ben Blow. It is captioned as follows: The new highway. Picture made in 1919.