California Governor Schwarzenegger wants to build two new dams -- Sites and Temperance Flat. They are being sold as necessary to cope with the reduction in Sierra Nevada, Cascade and Klamath Mountains snowpack expected as a result of climate change. New and "enhanced" storage are being marketed by Lester Snow, director of California's Department of Water Resources (DWR) as part of a "portfolio approach" which, in addition to "enhanced" storage, calls for urban water conservation, better groundwater facilities, improved wastewater processing and research into lowering the cost of desalination. The dams are to provide increased capacity in order to catch earlier runoff that -- according to climate change data and predictions -- will no longer be held in mountain snowpack.

Schwarzenegger and Snow are counting on the climate change predictions to be fairly accurate. If the actual climate does not follow the predictions, the new and "enhanced" reservoirs might never fill. Furthermore, increasing surface storage would result in more extensive water loss through evaporation. In 1998 the measured evaporation from California reservoirs was about a million acre feet -- that's enough water to cover a million acres of land with a foot of water. That's a lot of water but the amount will rise if new and "enhanced" reservoirs are developed. Furthermore, if climate change results in higher summer