Datum of gage (Displaying as NGVD29, also known as Hetch Hetchy Datum) is approximately 1.83 ft below NGVD of 1929 and 1.70 ft above NAVD of 1988.

Available data

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3 data types available - data from 2007-10-01 to 2026-08-12

1 data types available - data from 1930-10-01 to 2026-08-10

2 data types available - data from 1992-03-05 to 2026-06-24

0 observed properties (data types) available

0 data types available

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Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	11275500	n/a
Location name	HETCH HETCHY RES A HETCH HETCHY CA	n/a
Site type	Lake, Reservoir, Impoundment	LK
Decimal latitude (WGS84)	37.947686443274435	n/a
Decimal longitude (WGS84)	-119.7879220981649	n/a
Latitude-longitude method	Interpolated from map	M
Latitude-longitude accuracy	Accurate to + or - 5 sec.	F
District	California	06
State	California	06
County	Tuolumne County	109
Country	United States of America	n/a
Altitude of gage/land surface	1.7 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.16 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Upper Tuolumne	18040009
Drainage basin		n/a
Date of first construction		n/a
Drainage area	455 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	PST	n/a
Site honors Daylight Saving Time	Y	n/a
National aquifer		n/a
Local aquifer		n/a
Local aquifer type		n/a
Well depth		n/a
Hole depth		n/a
Source of depth data		n/a