The San Francisco Bay Regional Water Quality Control Board is a State of California agency responsible for regulating water quality in the Bay Area. Its jurisdiction includes San Francisco Bay, San Pablo Bay, Suisun Bay, Tomales Bay, and most of the waterways that flow into these water bodies. The region extends from the wineries in the Napa and Sonoma Valleys in the north, Silicon Valley in the south, and the Pacific Coast on the west, and includes a population of about 7 million in most of the nine Bay area counties. The Board's office is in downtown Oakland. Major cities in the region include San Francisco, Oakland, San Jose, Concord, San Rafael, Redwood City, Fairfield, Napa, and Sonoma.