A wet start to winter is boosting California's water supply. Lake Shasta, the state's largest reservoir, has risen by 36 feet since December 16th. It is 77 percent full and at 129 percent of its historical average for this time of year. Lake Oroville, the state's second largest reservoir, has risen by 69 feet in the same three-week period. It is 73 percent full and at 134 percent of its historical average. California's lakes have been filled with hundreds of billions of gallons of water thanks to the recent atmospheric river storms.