O'Shaughnessy Dam

O'Shaughnessy Dam (HML6)

Location: Groveland, CA 95321 Tuolumne County
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Country: United States of America
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N 37° 56.859', W 119° 47.273'

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(Tablet 1)
O'Shaughnessy Dam
City and County of San Francisco.
James Rolph Jr. Mayor

· Foundation Elev. 3388 · Bottom Valves Elev. 3508 · Initial Crest Elev. 3726 · Length of Crest 600· Storage Cap'y Gals. 66,000,000,000 · Drainage Area Acres 294,000 · Reservoir Area Acres 1590· Concrete Volume Cu. Yds. 390,000

M.M. O'Shaugnessy, Engineer
Utah Construction Co. Contr's.

(Tablet 2)
Structure Completed 1938 · Height Increased 68 Feet· Federal Emergency Administration of Public Works · Project No. 1429

Angelo J. Rossi, Mayor
Public Utilities Commission
· Lewis F. Byington, President · George Filmer, Vice President · John H. McCallum, Commissioner · John P. Murphy, Commissioner · John P. McLaughlin, Commissioner · EDW. G. Cahill, Mgr. of Utilities · M.M. O'Shaughnessy, Engineer, Design · L.T. McAfee, Engineer, Construction · Transbay Construction Co., Contractor

· Height Above Stream Bed, Ft. 312 · Height Above Foundation, Ft. 426 · Crest Elev. Ft. 3,812 · Crest Length, Ft. 900 · Storage Cap'y, Gals. 117,300,000,000· Watershed Area. Sq. Mi. 459 · Reservoir Area, Acres 1,972 · Concrete Volume. Cu. Yds. 675,000

(Tablet 3)
Canyon Power Tunnel
George Christopher, Mayor
Public Utilities Commission
· Stuart n. Greenberg, President · Thos. P. White, Vice Pres. · Thos. F. Stack · George F. Hansen · Bert Simon

Robert C. Kirkwood, Manager of Utilities
Oral L. Moore, General Manager Hetch Hetchy Water Supply

Length: O'Shaughnessy Dam to early intake - 10.1 miles
Dimensions: 14'-0" by 14'-6" Horseshoe
Capacity: 850 Cubic Feet Per Second

(Tablet 4)
75th Anniversary of the Completion of the O'Shaughnessy Dam
July 11, 1998
Hetch Hetchy Water and Power

and in recognition of the contributions of
Hetch Hetchy Water & Power Personnel
Tuolumne County, The U.S. Forest Service
The National Park Service

City and County of San Francisco
Willie L. Brown, Jr., Mayor

San Francisco Public Utilities Commission
· Victor G. Makras, President · Ann Moller Caen, Vice President, E. Denis Normandy, Commissioner · Robert K. Werbe, Commissioner · Frank L. Cook, commissioner

Anson B. Moran, General Manager SFPUC
Lawrence T. Klein, General Manager, HW&P
HM NumberHML6
Marker ConditionNo reports yet
Date Added Wednesday, October 15th, 2014 at 12:09pm PDT -07:00
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Locationbig map
UTM (WGS84 Datum)11S E 255033 N 4203673
Decimal Degrees37.94765000, -119.78788333
Degrees and Decimal MinutesN 37° 56.859', W 119° 47.273'
Degrees, Minutes and Seconds37° 56' 51.54" N, 119° 47' 16.38" W
Driving DirectionsGoogle Maps
Area Code(s)209
Closest Postal AddressAt or near 10-98 Dam, Groveland CA 95321, US
Alternative Maps Google Maps, MapQuest, Bing Maps, Yahoo Maps, MSR Maps, OpenCycleMap, MyTopo Maps, OpenStreetMap

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