Changes in California climate tied to water supply

Ventura County Star: Global climate change will have dramatic effects on California's water resources, reducing the Sierra snowpack by at least 25 percent by 2050, decreasing spring runoff into the Sacramento-San Joaquin Delta and contributing to more severe droughts. And state and local water agencies will have but one choice in dealing with all this: adapt.

That was the conclusion of experts who testified Thursday at a hearing of the State Water Resources Control Board — a hearing that Chairwoman Tam Dudoc called the state's "first formal forum on the nexus between climate change and water resources." Lester Snow, director of the Department of Water Resources, testified that the effects of climate change are great unknowns as the state makes plans to meet future water needs.

"Our water future is a lot more uncertain than our water past," he said. "Our droughts are going to get deeper and longer — that is not a question. The only question is: How much deeper and how much longer?" The effects of climate change, he said, have added urgency to such efforts as strengthening Delta levees and building additional water storage capacity.

Regional water experts testified the best strategies for dealing with the challenges are to increase conservation and to make better use of reclaimed water and local groundwater resources. Implementing those steps, they said, would not only maximize the state's water supply but also help reduce greenhouse gas emissions because they require far less energy than pumping more water from Northern California to the south…

Tim Brick, chairman of the Metropolitan Water District of Southern California, said the agency's experience in responding to the drought of the early '90s has provided "a model of adaptability" that will help meet future challenges.

… studies of the Colorado River watershed conclude that climate changes will result in a 10 percent to 40 percent reduction in river flows. "What we now consider a drought is going to be a permanent condition by 2040," he said.