Rivers in New Hampshire
Souhegan River at Merrimack
Below flood stage
2.38ftStage
Observed Thu, Sep 24, 10:30 AM EDT
- Flood stage
- 9.00 ft
- Forecast crest
- 3.10 ftSun, Sep 27, 8:00 AM EDT
- Record crest
- 16.20 ft1936
Flood stages and impacts
| Category | Stage |
|---|---|
| Major flood | 13.00 ft |
| Moderate flood | 11.00 ft |
| Minor flood | 9.00 ft |
| Action | 8.00 ft |
- 13.00 ftSignificant flooding affects homes in the area of Beacon Drive in Merrimack. Other low lying sections upstream into Amherst and Milford experience flooding.
- 11.00 ftIn Merrimack, homes in the Beacon Drive area flood. Other low lying areas upstream into Amherst and Milford flood.
- 10.00 ftIn Merrimack, several homes along a small portion of Beacon Drive begin to flood. In Amherst, low lying areas begin to flood.
- 9.00 ftFlooding of low lying areas along the river begins in the town of Merrimack.
Flood outlook
Chance of flooding, September to November
| Category | Chance |
|---|---|
| Minor flooding | Under 5% |
| Moderate flooding | Under 5% |
| Major flooding | Under 5% |
The three-month chances are the River Forecast Centers’ long-range flood outlook, issued September 21, 2026.
Crest history
47 crests on NOAA’s list since 1915.
| # | Date | Stage |
|---|---|---|
| 1 | March 19, 1936 | 16.20 ft |
| 2 | September 21, 1938 | 12.78 ft |
| 3 | April 17, 2007 | 12.71 ft |
| 4 | April 8, 1924 | 11.82 ft |
| 5 | June 25, 1944 | 10.88 ft |
| 6 | April 13, 1934 | 10.66 ft |
| 7 | March 13, 1936 | 10.60 ft |
| 8 | October 16, 1955 | 10.30 ft |
| 9 | April 7, 1987 | 10.25 ft |
| 10 | January 10, 1956 | 10.00 ft |
| 11 | October 22, 1996 | 9.96 ft |
| 12 | November 14, 1937 | 9.92 ft |
| 13 | May 15, 2006 | 9.88 ft |
| 14 | March 15, 2010 | 9.85 ft |
| 15 | April 2, 2004 | 9.84 ft |
| 16 | November 5, 1927 | 9.73 ft |
| 17 | August 5, 1915 | 9.60 ft |
| 18 | March 31, 2010 | 9.19 ft |
| 19 | December 15, 1920 | 9.18 ft |
| 20 | November 29, 1937 | 9.01 ft |
| 21 | April 17, 1996 | 8.86 ft |
| 22 | April 2, 1962 | 8.80 ft |
| 23 | March 22, 1983 | 8.74 ft |
| 24 | February 27, 1916 | 8.68 ft |
| 25 | September 12, 1954 | 8.62 ft |
Most recent crests
- December 19, 2023: 8.57 ft
- December 26, 2020: 7.52 ft
- December 15, 2019: 7.30 ft
- January 25, 2019: 7.26 ft
- October 31, 2017: 8.14 ft
- April 7, 2017: 7.06 ft
- March 31, 2010: 9.19 ft
- March 15, 2010: 9.85 ft
- April 17, 2007: 12.71 ft
- May 15, 2006: 9.88 ft
Nearby
Upstream, downstream and the gauges around this one.
What this means
Forecasts by the Northeast River Forecast Center. Forecasts are issued routinely year-round.
Sources
Stage, flood stages, impacts and crest history from NOAA’s National Water Prediction Service. Streamflow and the daily record from the U.S. Geological Survey.