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USGS 05020500 St. Mary River at International Boundary

PROVISIONAL DATA SUBJECT TO REVISION

Click to hidestation-specific text
Flood Tracking - Stage Flood Tracking - Discharge Gage-height Corrections Base Rating Shifted Rating
(About shift-adjusted ratings).
Station operated jointly by the USGS Wyoming-Montana Water Science Center and Water Survey Canada in cooperation with the U.S. Department of State and in accordance with the Boundary Waters Treaty of 1909 as overseen by the International Joint Commission and in cooperation with the U.S. Bureau of Reclamation .
Station photographs | 1 |
Leaving USGS: U.S. Coast Guard boating safety tips.
This station managed by the Helena Field Unit.

Available Parameters Available Period
  
1989-10-01  2026-06-12
2007-10-01  2026-06-12







 (7)
 
  -- or --

 

 
Summary of all available data for this site
Instantaneous-data availability statement

Discharge, cubic feet per second
Most recent instantaneous value: 1370 06-12-2026   11:10 MDT
Graph of Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Jun 12 based on 123 water years of record more
Min
(1941)		 Most Recent
Instantaneous
Value Jun 12		 25th
percen-
tile		 Median Mean 75th
percen-
tile		 Max
(1964)
629 1370 1580 2370 2680 3510 10100

Gage height, feet, [(2)]
Most recent instantaneous value: 5.39 06-12-2026   11:10 MDT
Graph of Gage height, feet, [(2)]

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