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Available data

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Continuous data

4 data types available - data from 1994-10-01 to 2026-08-18

Daily data

3 data types available - data from 1939-05-18 to 2026-08-18

Field measurements

4 data types available - data from 1962-06-19 to 2026-08-06

Discrete sample data

166 Observed properties (data types) available - with data from 1975-10-07 to 2020-09-09

449 Sampling activities

Peak measurements

2 data types available - with data from 1939-06-26 to 2025-06-03

Statistical tables for select daily data types

3 data types available - data from 1939-05-18 to 2026-08-17

Important information about this monitoring location

The elevation of zero gage height has been determined to be 3,336.74 feet above NAVD88. To obtain water‑surface elevation values in NAVD88, add 3,336.74 feet to gage height values.

Location details and information

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Operated in cooperation with:

Montana Department of Environmental Quality

Montana Department of Fish, Wildlife, and Parks

Montana Department of Natural Resources and Conservation

USGS - Cooperative Matching Funds

USGS - Federal Priority Streamgages

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	06307500	n/a
Location name	Tongue River at Tongue R Dam nr Decker MT	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	45.141275	n/a
Decimal longitude (WGS84)	-106.771356	n/a
Latitude-longitude method	Interpolated from digital map	N
Latitude-longitude accuracy	Accurate to + or - .1 sec (Differentially-Corrected GPS).	1
District	Montana	30
State	Montana	30
County	Big Horn County	003
Country	United States of America	n/a
Altitude of gage/land surface	3336.74 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.14 feet	n/a
Altitude datum	North American Vertical Datum of 1988	NAVD88
Subbasin hydrologic unit	Upper Tongue	10090101
Drainage basin		n/a
Date of first construction		n/a
Drainage area	1784 square miles	n/a
Contributing drainage area		n/a
Time zone abbreviation	MST	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 Tongue River at Tongue R Dam nr Decker MT - USGS-06307500