The Stone Dam from 1870, a historical treasure hidden within our local watershed. The beginning of our modern Peninsula is possible because of this.#history #Watershed #NPOST
Thank you to Open the SF Watershed for this share.
This is Stone Dam as it stands today in the San Francisco Watershed It was constructed in the 1870’s and stands approximately twenty five feet high. In the picture you can see Stone Dam Lake and a boathouse.
Famously San Francisco’s population exploded in 1849, and so did its thirst for water, the small springs in San Francisco were insufficient to supply the city’s growing population. The system for delivering water was so simple at that time that barrels of waters were sold, for exorbitant prices.
The Spring Valley Water Company, motivated by profit devised a plan to ship water via a Redwood Flume to San Francisco. The flume would ship the water via gravity from Pilarcitos Canyon to San Francisco.
Pialrcitos Canyon was forged by Pilarcitos Creek that runs down the canyon then turns west and runs parallel to what is now highway 92 and finally into the Pacific at Half Moon Bay.
It is here on Pilarcitos Creek in the lower part of the Canyon that the Halsteadt Brothers constructed a mill to pulverize flour with a thirty two foot wheel, powered by Pilarcitos Creek.
It was at this mill that the Spring Valley Water Company sent their representatives James Denniston and Josia Ames to purchase the land from the Halsteadt Brothers. The Spring Valley Water Company had no use for the mill, but was very interested in the water.
After purchasing the property the Spring Valley Water Company constructed two Dam. The larger one Pilarcitos Dam, and the smaller one in this photo, Stone Dam.
This history belongs to all of us, and this public site should be open to public viewing. This is only one of the reasons why we want to Open the SF Watershed to hikers!