Computed discharge may appear inaccurate due to downstream channel restoration affecting the stage‑discharge relationship. Extra measurements will improve accuracy, but some periods of inaccurate discharge may still occur.

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Available data

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Continuous data

4 data types available - data from 1988-10-01 to 2026-08-01

Daily data

2 data types available - data from 1970-10-01 to 2026-07-30

Field measurements

3 data types available - data from 1970-10-13 to 2026-07-24

Discrete sample data

8 Observed properties (data types) available - with data from 2014-12-09 to 2017-09-13

6 Sampling activities

Statistical tables for select daily data types

2 data types available - data from 1970-10-01 to 2026-07-30

Important information about this monitoring location

Computed discharge at this site may appear inaccurate due to channel restoration work downstream of the gage affecting the stage-discharge relationship. Extra measurements will be made to ensure accuracy, but periods of inaccurate computed discharge may remain between measurements.

Location details and information

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Operated in cooperation with:

San Francisco Hetch Hetchy Water and Power, City and County of

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	11289650	n/a
Location name	TUOLUMNE R BL LAGRANGE DAM NR LAGRANGE CA	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	37.66629745522321	n/a
Decimal longitude (WGS84)	-120.4421023410243	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	Stanislaus County	099
Country	United States of America	n/a
Altitude of gage/land surface	172.6 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	1538 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

Monitoring location Tuolumne R BL Lagrange Dam NR Lagrange CA - USGS-11289650