Here in California, we’ve been on a roller coaster when it comes to water. After five years of crippling drought, the Golden State had one of its wettest winters on record. So what has all the rain and snow meant for our water supply in Southern California? It depends on where you live and where your water comes from. About thirty percent of Southern California’s water comes from far, far away: Lake Oroville, a giant reservoir in the Sierra Nevada about 80 miles north of Sacramento.