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Cockermouth River at Groton

Highest listed crest 11.82 ftFlood stage 9.5 ft4 crests since 2011

The Cockermouth River at Groton crested above flood stage 3 times among the 4 crests the National Weather Service lists from 2011 to 2023. The highest, 11.82 ft on October 30, 2017, was moderate flooding, 2.32 feet above flood stage.

The gauge

Highest listed crest
11.82 ft
October 30, 2017; 7,900 cubic feet per second
Flood stage
9.5 ft
Major flooding from 12.0 ft
Crests at major
0
3 above flood stage
Most recent flood crest
December 23, 2022
9.75 ft, minor flooding
Location
Grafton County
New Hampshire

Flood stages

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

Flood categories, Cockermouth River at Groton
Action stage8.51Dec 18, 2023The level at which the NWS or its partners begin to take action
Flood stage (minor)9.51Dec 23, 2022Minimal or no property damage, but possibly some public threat
Moderate flood stage10.02Oct 30, 2017Some inundation of structures and roads near the stream
Major flood stage12.00—Extensive inundation of structures and roads

Every listed crest

4 crests from 2011 to 2023. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Cockermouth River at Groton, 2011 to 2023 9101112ft Flood stage 9.5 ftMajor 12.0 ft Aug 28, 2011: 11.17 ft, moderate flooding; 5,260 cubic feet per secondOct 30, 2017: 11.82 ft, moderate flooding; 7,900 cubic feet per secondDec 23, 2022: 9.75 ft, minor flooding; 3,500 cubic feet per secondDec 18, 2023: 9.25 ft, action stage; 3,080 cubic feet per second Highest, 11.82 ft, Oct 30, 2017 20152020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Cockermouth River at Groton 2010s: 2 2 2020s: 1 2010s2020s
  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, Cockermouth River at Groton
1Oct 30, 201711.82+2.32Moderate7,900
2Aug 28, 201111.17+1.67Moderate5,260
3Dec 23, 20229.75+0.25Minor3,500
4Dec 18, 20239.25−0.25Action3,080

Other gauges in Grafton County

Flood gauges in Grafton County
Bethlehem8.012.34 ft, Nov 12, 19950
Rumney10.017.40 ft, Nov 3, 19272
West Lebanon23.035.00 ft, Nov 4, 19274
Plymouth13.029.00 ft, Mar 19, 19368
Woodstock9.016.97 ft, Aug 28, 20112

Grafton County: every hazard · River floods across the country · New Hampshire

NOAA National Water Prediction Service, gauge GRTN3, 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.