Monday, May 11, 2009 | Back in 2006, Tim Barnett sketched a grim future when asked about the impact climate change would have on San Diego’s water supply.
The warming climate, Barnett said then, would bring water cops, limits on lawn watering and trouble for salmon in the Sacramento River, one of San Diego’s major water sources.
“I believe the environment will eat it first,” said Barnett, a marine physicist at Scripps Institution of Oceanography. “Do you want to go thirsty or kill off the last salmon in the Sacramento River?”
Three years later, San Diego has adopted specific lawn-watering days, which start June 1. The city will spend $756,000 to hire 10 water cops. The salmon population on the Sacramento River plummeted to historic lows last year, prompting an unprecedented closure of commercial salmon fishing from the U.S.-Mexico border to Oregon.
The drier future that Barnett predicted is becoming reality. And today, Barnett is warning of worse things to come. As the climate continues to warm, the Southwest, from San Diego and Los Angeles to Las Vegas and Phoenix, will have to cope with less water, he said.
Barnett projects that in 40 years, the warming climate will reduce runoff into the Colorado River so much that shortages will be more common than surpluses. The seven states that rely on the Colorado, a major source of San Diego’s water, will have to handle shortages in as much as nine out of every 10 years. Shortages could hit in four out of every 10 years by 2025.