The most unusual part of the Bay Area's water infrastructure are the two water temples.
Sunol Water Temple
The Sunol Water Temple was built in 1910 to "memorialize the convergence of three sources of water – Alameda Creek, the Arroyo de la Laguna, and the Pleasanton Well Fields". Before the San Francisco Public Utilities Commission came into existence, the Spring Valley Water Company was providing clean water for citizens of San Francisco. The SVWC drained waters in this area and used aqueducts and the Niles Canyon Creek to bring the water to San Francisco.
William Bowers Bourn, the SVWC president, hired architect Willis Polk to build this Temple as a tribute to the mission of the aqueduct. The inscription around the top reads: "I will make the wilderness a pool of water and the dry lands springs of water. The streams whereof shall make glad the city."
In the 1920's, this aqueduct provided about half of San Francisco's water supply. To this day, it continues to be one of the three main watersheds supplying water into the city, although after 1934 dwarfed by Hetch Hetchy.
Pulgas Water Temple
This temple was built in 1934, twenty-four years after the Sunol temple, at the completion of the Hetch Hetchy aqueduct system. The inscription here reads "I give waters in the wilderness and rivers in the desert, to give drink to my people", again from Isaiah. The architect who designed the structure was William G. Merchant, a prominent San Francisco architect who served on the Architecture Board for the Golden Gate International Exposition.
The San Francisco Public Utilities Commission is not frequently tasked with administering parks, so the rules are a little unusual. Alcohol, "dogs and pets", fires, bicycling and rollerblading are completely forbidden, and parking is limited to 30 minutes only.