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Prospect Creek at Thompson Falls

Highest listed crest 9.86 ftFlood stage 7.5 ft16 crests since 1956

The Prospect Creek at Thompson Falls crested at major flood stage 2 times among the 16 crests the National Weather Service lists from 1956 to 2025. The highest, 9.86 ft on January 16, 1974, was major flooding, 2.36 feet above flood stage.

The gauge

Highest listed crest
9.86 ft
January 16, 1974; 5,490 cubic feet per second
Flood stage
7.5 ft
Major flooding from 9.0 ft
Crests at major
2
20th of 93 gauges in Montana
Most recent flood crest
March 19, 2017
8.10 ft, moderate flooding
Location
Sanders County
Montana

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Prospect Creek at Thompson Falls
Action stage6.55Apr 25, 2012The level at which the NWS or its partners begin to take action
Flood stage (minor)7.52May 13, 1971Minimal or no property damage, but possibly some public threat
Moderate flood stage8.01Mar 19, 2017Some inundation of structures and roads near the stream
Major flood stage9.02Feb 9, 1996Extensive inundation of structures and roads

Every listed crest

16 crests from 1956 to 2025. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Prospect Creek at Thompson Falls, 1956 to 2025 246810ft Flood stage 7.5 ftMajor 9.0 ft May 21, 1956: 7.60 ft, minor flooding; 2,860 cubic feet per secondMay 13, 1971: 7.60 ft, minor flooding; 2,860 cubic feet per secondJun 1, 1972: 7.09 ft, action stage; 2,430 cubic feet per secondJan 16, 1974: 9.86 ft, major flooding; 5,490 cubic feet per secondMay 11, 1976: 7.09 ft, action stage; 2,850 cubic feet per secondFeb 9, 1996: 9.54 ft, major flooding; 5,160 cubic feet per secondMay 17, 1997: 6.94 ft, action stage; 2,680 cubic feet per secondApr 14, 2002: 6.23 ft, below flood stage; 2,160 cubic feet per secondMay 19, 2008: 7.27 ft, action stage; 3,030 cubic feet per secondApr 25, 2012: 6.52 ft, action stage; 2,370 cubic feet per secondMar 19, 2017: 8.10 ft, moderate flooding; 3,640 cubic feet per secondMay 31, 2020: 4.54 ft, below flood stage; 1,210 cubic feet per secondMay 2, 2021: 3.99 ft, below flood stage; 904 cubic feet per secondMay 7, 2022: 5.01 ft, below flood stage; 1,510 cubic feet per secondMar 28, 2025: 3.55 ft, below flood stage; 692 cubic feet per secondDec 11, 2025: 6.35 ft, below flood stage; 2,370 cubic feet per second Highest, 9.86 ft, Jan 16, 1974 1960197019801990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Prospect Creek at Thompson Falls 1950s: 1 1960s: 0 1970s: 2 2 1980s: 0 1990s: 1 2000s: 0 2010s: 1 2020s: 0 1950s1960s1970s1980s1990s2000s2010s2020s
  1. These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
  2. Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.

Highest crests

Highest listed crests, Prospect Creek at Thompson Falls
1Jan 16, 19749.86+2.36Major5,490
2Feb 9, 19969.54+2.04Major5,160
3Mar 19, 20178.10+0.60Moderate3,640
4May 21, 19567.60+0.10Minor2,860
5May 13, 19717.60+0.10Minor2,860
6May 19, 20087.27−0.23Action3,030
7Jun 1, 19727.09−0.41Action2,430
8May 11, 19767.09−0.41Action2,850
9May 17, 19976.94−0.56Action2,680
10Apr 25, 20126.52−0.98Action2,370
11Dec 11, 20256.35−1.15Below flood stage2,370
12Apr 14, 20026.23−1.27Below flood stage2,160
13May 7, 20225.01−2.49Below flood stage1,510
14May 31, 20204.54−2.96Below flood stage1,210
15May 2, 20213.99−3.51Below flood stage904
16Mar 28, 20253.55−3.95Below flood stage692

Other gauges in Sanders County

Flood gauges in Sanders County
Plains16.019.17 ft, Jun 5, 19480
Thompson Falls7.08.53 ft, Jun 9, 19640

Sanders County: every hazard · River floods across the country · Montana

NOAA National Water Prediction Service, gauge PRCM8, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.