State officials said Wednesday that Californians reliant on water pumped out of the Sacramento-San Joaquin Delta won’t face supply shortages, even as crews shut down a massive pumping station that serves much of Southern California for at least a month to make repairs to its intake reservoir. The repair effort involves Clifton Court Forebay, a shallow reservoir that serves as an entryway for a Delta pumping station critical to the State Water Project, the state-run water delivery network that moves water north to south through California.