Do you think you could reduce your water use by 40 percent? What if we asked for even more than that? This is the type of rationing we can expect during a severe drought if a new proposal from the State Water Resources Control Board is implemented. The San Francisco Public Utilities Commission is the retail water provider for San Francisco and the water provider for 26 wholesale customers in San Mateo, Santa Clara and Alameda counties. Today, 85 percent of the water we deliver to our customers comes from the Tuolumne River.