Northern California is enjoying a rather wet December, and the rainfall has helped increase the state's largest water reservoir from 26 percent to 31 percent capacity, but still needs as much rain as possible. The state still needs 11 trillion gallons of water to recover from three years of relatively mild winters, according to NASA satellite data.
Mandatory water restrictions occurred throughout the state over the summer, with low water levels in reservoirs and lakes, while also hurting agriculture. Since 2011, there has been a decreased volume of four trillion gallons of water per year at the Sacramento and San Joaquin river basins.
"We will need two or three winters of above average precipitation," said Jay Famiglietti from the NASA Jet Propulsion Laboratory, in a statement made to CBS News during the American Geophysical Union (AGU) conference in San Francisco. "Every rain storm is like a deposit in a bank account by the size of the deficit is so big. We are going to need a lot of rain to accumulate that storage."