Climate change is another driver in the argument for an Auburn Dam, as this article, though focusing on the Tuolumne River, makes well.
An excerpt.
Early melt makes flood more likely
Experts: Rising temps alter progress of snow to valley
By MICHAEL G. MOONEYBEE STAFF WRITER
Last Updated: October 8, 2006, 05:23:44 AM PDT
The water collection, storage and distribution that today is the linchpin of the California economy was built around the premise of catching water produced by slowly melting Sierra snow.
Traditionally, the mountain snow begins melting about April 1 and is through by the end of July. A series of reservoirs collects the water as it weaves its way from the Sierra to the valley floor.
During the winter months, reservoir levels are controlled through dams — release flows are gauged to leave enough space in the reservoir to collect water during the runoff without flooding downstream farms and cities.
But if scientists and researchers are correct, the worldwide temperature increase already under way is changing the dynamics, perhaps permanently.
Wes Monier, strategic issues and planning manager at the Turlock Irrigation District, says utility records show the Sierra snowpack is melting before April 1.
In recent years, he said, the snowmelt has started between the middle and the end of March.
An earlier snowmelt, coupled with warm late-winter and early spring rains, causes reservoirs to fill much faster — bringing some potentially dire consequences in the process.
That happened this past winter and spring, forcing dam operators to release millions of acre-feet of water into rivers such as the Tuolumne to avoid severe flooding.
The plan worked. There were no major levee failures and no major flooding — this time.
As the world's climate continues to change, however, experts say the valley won't fare as well.
Edwin Maurer of Santa Clara University and other experts say the region almost certainly will experience more frequent large-scale flooding, similar to what happened during the winter of 1997.
