In 1906, William Bowers Bourn II, a major stockholder in the Spring Valley Water Company, and owner of the giant Empire gold mine, hired Willis Polk to design a “water temple” atop the spot where three subterranean water sources converge [a pipe from the Arroyo de la Laguna; Alameda Creek through the Sunol filter galleries; and a pipeline from the artesian well field of Pleasanton].

Polk’s design was modeled after the ancient Temple of Vesta in Tivoli, Italy. (Tivoli is where many of the waters that fed Rome converged in the foothills of the Apennines.) Prior to the construction of the Hetch Hetchy Aqueduct, half of San Francisco’s water supply (6 million gallons a day) passed through the Sunol temple.

Some sources claim that Bourn, anticipating the sale of the water company to the City of San Francisco, saw the temple as a means to appeal to San Francisco voters. Others believe that, as a wealthy and classically-educated citizen, Bourn was motivated by a sense of civic responsibility. Either way, it was finally constructed in 1910.

Inside the temple, water flowed into a white tiled cistern before plunging into a deeper water channel carrying water from the filter galleries to the Niles Aqueduct in Niles Canyon and across San Francisco Bay near the Dumbarton Bridge.

Bourn was regularly pilloried by the San Francisco Chronicle as a thief and scoundrel for water rates. But he reasoned that the company deserved a return on its investments and was providing for metropolitan growth.

The 59-foot-high classical pavilion is made up of twelve concrete Corinthian columns and a concrete ring girder that supports a wood and red tile roof. (Corinthian: “of or relating to the lightest and most ornate of the three ancient Greek architectural orders distinguished especially by its large capitals decorated with carved acanthus leaves.”)

The terra cotta roof elements were fabricated by Gladding McBean Tile Company of Los Angeles. The roof is partially supported by elaborately decorated beams. Wedge-shaped paintings also adorn the ceiling. The paintings depict Native American maidens carrying water vessels. The painted wood ceiling was created by Yun Gee and other artists.

Visitors approach Sunol Temple on a long ceremonial drive. A grove of Lombard poplars surrounds the temple, and a ridge of hills rises behind it.

Though the waters were once used for San Francisco’s water supply before construction of the Hetch Hetchy system, only a small amount is diverted for local SFPUC uses today. The rest is released into Alameda Creek.

The Sunol Water Temple was designated as a California Historical Engineering Landmark in 1976 by the American Society of Civil Engineers.