Background & History
Windmills, including the Murphy Windmill and the Dutch Windmill to the north, are structures that harness the power of wind energy to perform work. Throughout history, windmills have been used to grind wheat, cut wood, generate electricity, and pump water. Golden Gate Park's windmills were used to pump water for irrigating the park's plants and trees.
Windmills have sail stocks or vanes that are attached to the central axis shaft as well as gears located in the dome. The wind pushes against the sail stocks, causing them to rotate, which spins the shaft. The gears in the dome are connected to a vertical shaft which runs down through the tower to a pump mechanism located on the ground floor. Gears attached to the drive shaft use the rotational energy to pump water or generate electricity depending on the purpose or function of the windmill.
The Murphy Windmill was designed and constructed in Golden Gate Park between 1905 and 1907, a gift to the City by Samuel G. Murphy. It is the second of two windmills built in the Park, the first being the northern Dutch Windmill, which was constructed in 1902. The Murphy Windmill is commonly believed to be the largest windmill of its kind in the world. The pair standing together are often referred to as the "San Francisco Giants."
The windmill design, by a Bay Area
engineer named J.C.H. Stut, incorporated mechanical elements of both Dutch and European influence, along with his own unique, innovative western touches. Standing in excess of 95' tall, the Murphy Windmill pumped water from the West Basin Aquifer, located approximately 200 feet below the park's surface. The original location of the well is unknown; however a pump in the well house brought water into a storage pond just west of the windmill. It is estimated that the windmill ran up to twelve hours a day, pulling water from the pond and pumping it up to Strawberry Hill. The reservoir at Strawberry Hill provided the irrigation water source for the entire park east of 19th Avenue; the water that wasn't used for the east half overflowed down Huntington Falls into Stow Lake which provided irrigation water west of 19th Avenue. The park's irrigation system at the time was prssurized by gravity alone.
The Murphy Windmill and Dutch Windmill were said to have pumped up to 1.5 million gallons of water every day, transforming the existing sand dunes into a green oasis. Prior to the construction of the windmills, the City of San Francisco hired sprinkling wagons to haul water through the park and irrigate the land. The windmills were no longer used after 1935 when modern irrigation systems were installed.