A helpful tipster sends us word today of line graphs bearing bad news about the current water content of the California snow pack. The graphs have lines for the current year, wet and dry years (represented by 1976-77 and 1982-83, respectively), an average year, and last year. So far this year, the water content in the state's snow pack is an absolute disaster, rivaling the worst years on record and making last year's replenishing precipitation seem like a mirage. To make matters worse, the lack of snow spans all regions of the state that contribute to the water supply, from the very northern regions of Trinity County down to the Owens Valley.
Why does the snow pack matter? As explained by the Department of Water Resources, the snow pack contributes almost a third of the state's water supply, and it's particularly helpful because snow melts during drier spring and summer months when rain is no longer adding to the state's water storage systems. Los Angeles is always on the downstream end of those systems--for instance, in 2010, the LADWP received 48 percent of its supply from imported Metropolitan Water District sources (e.g., the Colorado River and the State Water Project) and 36 percent percent of its supply from the Los Angeles Aqueduct (i.e., water imported from the Owens Valley), according to a recent NRDC post.
· California Snow Water Content [CA Department of Water Resources]
· Southern California's New Wave of Local Water Supplies [NRDC Switchboard]
· Climate Change Page [CA Department of Water Resources]