San Lorenzo River after the Storm photo via spicycarrots.com

By Bonnie Hulkower, New York, New York on 01.25.10 …While this week of rain has brought some relief to water officials, much more rain and snow is needed to pull California out of its three-year drought. The state could emerge from drought, but only if the rain is persistent, and is complemented by heavy snowfall in the mountains. Rainfall has been above average in the Bay Area, and officials from San Francisco Public Utilities Commission have been expressing optimism about the levels of Hetch Hetchy reservoir, the source of the San Francisco’s drinking water, which is now at 72% capacity. But the story at Lake Oroville, the state water project’s primary drinking water source is quite different. Lake Oroville is only at 31% of it capacity. Lake Oroville, has a capacity of 3.5 million acre-feet of water. Hetch Hetchy is much smaller, only holding 360,400 acre-feet of water. The state’s largest reservoir, Shasta Lake, can hold 4.5 million acre-feet, but is currently only half full. Capacity is difficult to gauge because a percentage needs to be left for flood control and fish passage. In addition to these concerns, there are also issues with aging infrastructure and environmental disputes limiting the amount of water pumped through the Delta. The National Academy of Sciences is meeting tomorrow to examine whether the federal government should lift or modify limits on pumping from California’s delta. As of now, a little more than 23 inches of rain has fallen in the northern Sierra. On average, 50 inches of rain falls each year, meaning another 27 inches would have to fall this year just to reach normal levels. The telltale measurement will be on April 1, which is considered the peak for snowpack. But even if this year is a good year to bring the reservoirs back to a decent level, if next year is dry, it will push the state right back into drought. …

It’s raining, It’s pouring in California…but the drought isn’t over yet