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Ammonoosuc River at Bethlehem

Highest listed crest 12.34 ftFlood stage 8.0 ft22 crests since 1950

The Ammonoosuc River at Bethlehem crested above flood stage 22 times among the 22 crests the National Weather Service lists from 1950 to 2024. The highest, 12.34 ft on November 12, 1995, was moderate flooding, 4.34 feet above flood stage.

The gauge

Highest listed crest
12.34 ft
November 12, 1995; 11,300 cubic feet per second
Flood stage
8.0 ft
Major flooding from 14.0 ft
Crests at major
0
22 above flood stage
Most recent flood crest
April 12, 2024
8.63 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, Ammonoosuc River at Bethlehem
Action stage6.00—The level at which the NWS or its partners begin to take action
Flood stage (minor)8.019Apr 12, 2024Minimal or no property damage, but possibly some public threat
Moderate flood stage12.03Dec 18, 2023Some inundation of structures and roads near the stream
Major flood stage14.00—Extensive inundation of structures and roads

Every listed crest

22 crests from 1950 to 2024. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Ammonoosuc River at Bethlehem, 1950 to 2024 8101214ft Flood stage 8.0 ftMajor 14.0 ft Nov 26, 1950: 10.86 ft, minor flooding; 8,690 cubic feet per secondMar 27, 1953: 11.22 ft, minor flooding; 9,270 cubic feet per secondSep 11, 1954: 10.62 ft, minor flooding; 8,300 cubic feet per secondDec 21, 1957: 8.98 ft, minor flooding; 6,110 cubic feet per secondOct 24, 1959: 12.09 ft, moderate flooding; 10,800 cubic feet per secondApr 25, 1968: 9.09 ft, minor flooding; 5,960 cubic feet per secondJun 30, 1973: 11.96 ft, minor flooding; 10,600 cubic feet per secondDec 21, 1973: 10.69 ft, minor flooding; 8,410 cubic feet per secondFeb 12, 1981: 9.00 ft, minor flooding; 5,830 cubic feet per secondJan 27, 1986: 10.14 ft, minor flooding; 7,520 cubic feet per secondApr 1, 1987: 10.14 ft, minor flooding; 7,520 cubic feet per secondApr 29, 1988: 9.84 ft, minor flooding; 7,050 cubic feet per secondNov 12, 1995: 12.34 ft, moderate flooding; 11,300 cubic feet per secondApr 9, 2000: 9.26 ft, minor flooding; 6,200 cubic feet per secondDec 18, 2000: 10.09 ft, minor flooding; 7,440 cubic feet per secondApr 14, 2002: 9.22 ft, minor flooding; 6,140 cubic feet per secondApr 24, 2005: 9.91 ft, minor flooding; 7,160 cubic feet per secondAug 28, 2011: 10.90 ft, minor flooding; 8,600 cubic feet per secondApr 15, 2014: 9.75 ft, minor flooding; 6,730 cubic feet per secondDec 24, 2022: 9.24 ft, minor flooding; 5,974 cubic feet per secondDec 18, 2023: 12.15 ft, moderate flooding; 10,920 cubic feet per secondApr 12, 2024: 8.63 ft, minor flooding; 5,134 cubic feet per second Highest, 12.34 ft, Nov 12, 1995 19501960197019801990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Ammonoosuc River at Bethlehem 1950s: 5 5 1960s: 1 1970s: 2 1980s: 4 1990s: 1 2000s: 4 2010s: 2 2020s: 3 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.
  3. 1 crest measured on an earlier gauge datum is left out: 11.24 ft on Mar 18, 1936.

Highest crests

Highest listed crests, Ammonoosuc River at Bethlehem
1Nov 12, 199512.34+4.34Moderate11,300
2Dec 18, 202312.15+4.15Moderate10,920
3Oct 24, 195912.09+4.09Moderate10,800
4Jun 30, 197311.96+3.96Minor10,600
5Mar 27, 195311.22+3.22Minor9,270
6Aug 28, 201110.90+2.90Minor8,600
7Nov 26, 195010.86+2.86Minor8,690
8Dec 21, 197310.69+2.69Minor8,410
9Sep 11, 195410.62+2.62Minor8,300
10Jan 27, 198610.14+2.14Minor7,520
11Apr 1, 198710.14+2.14Minor7,520
12Dec 18, 200010.09+2.09Minor7,440
13Apr 24, 20059.91+1.91Minor7,160
14Apr 29, 19889.84+1.84Minor7,050
15Apr 15, 20149.75+1.75Minor6,730
16Apr 9, 20009.26+1.26Minor6,200
17Dec 24, 20229.24+1.24Minor5,974
18Apr 14, 20029.22+1.22Minor6,140
19Apr 25, 19689.09+1.09Minor5,960
20Feb 12, 19819.00+1.00Minor5,830
21Dec 21, 19578.98+0.98Minor6,110
22Apr 12, 20248.63+0.63Minor5,134

Other gauges in Grafton County

Flood gauges in Grafton County
Rumney10.017.40 ft, Nov 3, 19272
Groton9.511.82 ft, Oct 30, 20170
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 BETN3, 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.