Overview | |
---|---|
Coordinates | 37°46′24″N 122°30′32″W / 37.773356°N 122.508984°W (south portal) |
Status | Active |
Operation | |
Opened | 1915 |
Character | sewer tunnel (currently used for storm drain overflow) |
Technical | |
Length | 4,233 feet (1,290 m) long |
Mile Rock Tunnel is a utility tunnel in San Francisco, in the U.S. state of California that was originally constructed as the storm sewer outfall draining the Sunset, West Mission, Richmond, and Ingleside districts.
History
The Mile Rock Tunnel started construction in 1914 and was completed by 1915.[1] The contract was initially awarded to Edward Malley, but he stopped work after five months because of the high cost of insurance; R.C. Storrie and Company, who were responsible for other large tunneling projects including the Twin Peaks Tunnel, assumed responsibility for the work in January 1915.[1]
Mayor 'Sunny Jim' Rolph and other officials, including City Engineer M.M. O'Shaughnessy performed an inspection of the completed tunnel using a car on August 26, 1915. The tunnel was fitted with temporary structures and lighting to allow the car to enter without the threat of flooding from the outlet, but as it was not wide enough to allow the car to turn around, the return trip was conducted in reverse gear.[1]
Design
The tunnel was constructed by a combination of cut-and-cover (through soil) and boring (through rock) methods.[1]
See also
References
- 1 2 3 4 Maniery, Mary L. (February 1995). Historic American Engineering Record: Mile Rock Tunnel (PDF) (Report). National Park Service, Western Region, Department of the Interior. Retrieved 27 July 2018.
External links
- Sarah B. (26 July 2012). "What lies beneath: the Richmond District's Mile Rock Tunnel". Richmond District Blog. Retrieved 27 July 2018.
- Historic American Engineering Record (HAER) No. CA-162, "Mile Rock Tunnel, Under Forty-eighth Avenue from Cabrillo Street to San Francisco Bay at Point Lobos, San Francisco, San Francisco County, CA", 19 photos, 12 data pages, 2 photo caption pages
- McCarthy, W. N. (29 January 1910). "Homeseekers find Oceanside ideal". San Francisco Call. Retrieved 27 July 2018.
- "Big tube will soon be built". San Francisco Call. 23 April 1910. Retrieved 27 July 2018.
- "Right of way for main". San Francisco Call. 29 October 1912. Retrieved 27 July 2018.