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Water-Year Summary for Site 11162750

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  • Water-Year Summary reports summarize a year of hydrologic data in a printer-friendly format.
  • For water years 2014 onward, choose a water year and parameter and an on-demand Water-Year Summary report will be generated.
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Available Parameters
62615 Elevation, lake/res, NAVD88(Max.,Min.)  

Water year 2023: 2022-10-01 to 2023-09-30

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USGS Water-Year Summary 2023
11162750 Lower Crystal Springs Reservoir near San Mateo, CA
LOCATION - Lat 37°30'55", long 122°21'21" referenced to North American Datum of 1983, San Mateo County, CA, Hydrologic Unit 18050004, in Pulgas Land Grant, on east side, 0.45 mi north of Highway 92, 1 mi south of Crystal Springs Dam, and 3.6 mi southwest of San Mateo.
DRAINAGE AREA - 29.8 mi².
PERIOD OF RECORD - October 1998 to current year. Published as "Crystal Springs Reservoir at Dam, near San Mateo" prior to September 2007 and as "at dam" October 2007 to September 2010.
GAGE - Water-stage recorder. Datum of gage is NAVD of 1988. Prior to Feb. 11, 2011, datum of gage was NGVD of 1929.
REMARKS - Reservoir is formed by gravity type, interlocking concrete blocks and stores water from Hetch-Hetchy Aqueduct and local runoff for municipal use. Storage began in 1888. Dam was raised in 1890 and 1911. Spillway was raised and widened in 2012. Capacity is 68,865 acre-ft, spillway at crest is 294.6 ft above NAVD of 1988 (from San Francisco Public Utilities Commission survey). Normal maximum operating level is 290.6 ft with maximum reservoir operating level at crest.