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Available data

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Continuous data

4 data types available - data from 1994-10-01 to 2026-07-31

Daily data

4 data types available - data from 1960-07-08 to 2026-07-30

Field measurements

4 data types available - data from 1963-06-06 to 2026-07-16

Discrete sample data

539 Observed properties (data types) available - with data from 1965-10-01 to 2025-09-09

861 Sampling activities

Statistical tables for select daily data types

4 data types available - data from 1960-07-08 to 2026-07-29

Important information about this monitoring location

The elevation of zero gage height has been determined to be 3,431.00 feet above NAVD 1988. To obtain stream water-surface elevation values in NAVD 1988, add 3,431.00 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

Metadata Element	Location Metadata	Metadata Code
Agency	U.S. Geological Survey	USGS
Location identification number	06306300	n/a
Location name	Tongue River at State Line nr Decker MT	n/a
Site type	Stream	ST
Decimal latitude (WGS84)	45.00913611111111	n/a
Decimal longitude (WGS84)	-106.83594444444444	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	3431 feet	n/a
Method altitude determined	GNSS2 - Level 2 Quality Survey Grade Global Navigation Satellite System	X
Altitude accuracy	0.23 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	1453 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 State Line nr Decker MT - USGS-06306300