New Hampshire has 663 dams with recorded heights. The tallest is Comerford at 170 feet. Taller dams impound more water and carry greater potential energy, which is why height is a key factor in hazard classification and inspection requirements.
| # | Dam | County | Height (ft) | Type | Purpose | Hazard | Year |
|---|---|---|---|---|---|---|---|
| 1 | Comerford | Grafton | 170 | Concrete | Hydroelectric | High | 1930 |
| 2 | Moore | Grafton | 149 | Concrete | Hydroelectric | High | 1957 |
| 3 | Otter Brook Dam | Cheshire | 119 | Gravity | Flood Risk Reduction | High | 1958 |
| 4 | Franklin Falls Dam | Merrimack | 116 | Rockfill | Flood Risk Reduction | High | 1943 |
| 5 | Everett Dam | Hillsborough | 115 | Rockfill | Flood Risk Reduction | High | 1961 |
| 6 | Murphy Dam | Coos | 106 | Earth | Recreation | High | 1938 |
| 7 | Whitewater Brook Dam | Sullivan | 95 | Earth | Water Supply | High | 1968 |
| 8 | Surry Mountain Dam | Cheshire | 83 | Rockfill | Flood Risk Reduction | High | 1941 |
| 9 | Ayers Island | Grafton | 80 | Concrete | Hydroelectric | Significant | 1924 |
| 10 | Souhegan River Site 26 Dam | Hillsborough | 79 | Earth | Flood Risk Reduction | High | 1965 |
| 11 | Hopkinton Dam - Dike H-2 | Merrimack | 77 | Earth | Flood Risk Reduction | High | 1962 |
| 12 | Blackwater Dam | Merrimack | 75 | Gravity | Flood Risk Reduction | High | 1941 |
| 13 | Souhegan River Site 25b Dam | Hillsborough | 74 | Earth | Flood Risk Reduction | High | 1967 |
| 14 | Hopkinton Dam | Merrimack | 71 | Rockfill | Flood Risk Reduction | High | 1962 |
| 15 | Baker River Site 2 Dam | Grafton | 68 | Earth | Flood Risk Reduction | High | 1965 |
| 16 | Baker River Site 6a Dam | Grafton | 68 | Earth | Flood Risk Reduction | High | 1975 |
| 17 | Gregg Falls | Hillsborough | 66 | Concrete | Hydroelectric | High | 1917 |
| 18 | Hopkinton Dam - Dike H-3 | Merrimack | 66 | Earth | Flood Risk Reduction | High | 1962 |
| 19 | Minnewawa | Cheshire | 63 | Concrete | Hydroelectric | High | 1923 |
| 20 | Baker River Site 8 Dam | Grafton | 63 | Earth | Flood Risk Reduction | High | 1967 |
| 21 | Edward Macdowell Dam | Hillsborough | 63 | Earth | Flood Risk Reduction | High | 1950 |
| 22 | Gunnison Lake Site D2 Dam | Sullivan | 62 | Earth | Flood Risk Reduction | High | 1983 |
| 23 | Locke 2 Dam | Grafton | 60 | Earth | Recreation | Low | 1969 |
| 24 | Wilder | Grafton | 59 | Concrete | Hydroelectric | High | 1950 |
| 25 | Souhegan River Site 10a Dam | Hillsborough | 59 | Earth | Flood Risk Reduction | High | 1966 |
| 26 | Vernon | Cheshire | 58 | Concrete | Hydroelectric | Low | 1909 |
| 27 | Cascade | Coos | 57 | Concrete | Hydroelectric | High | 1903 |
| 28 | First Connecticut Lake Dam | Coos | 56 | Earth | Hydroelectric | High | 1930 |
| 29 | Balsams Mohawk River Dam | Coos | 55 | Earth | Recreation | Significant | |
| 30 | Arlington Mills Res Wheeler Dam | Rockingham | 54 | Concrete | Water Supply | High | 1922 |
| 31 | Baker River Site 5 Dam | Grafton | 53 | Earth | Flood Risk Reduction | High | 1967 |
| 32 | Oliverian Dam | Grafton | 52 | Earth | Flood Risk Reduction | High | 1962 |
| 33 | Everett Dam - Dike P-1 | Hillsborough | 50 | Rockfill | Flood Risk Reduction | High | 1961 |
| 34 | Ragged Mountain Snow Pond Dam | Merrimack | 49 | Earth | Fish and Wildlife Pond | Low | 1988 |
| 35 | Badger Brook Nh-107 Embankment Dam | Belknap | 48 | Fish and Wildlife Pond | Undetermined | ||
| 36 | Bellows Falls | Cheshire | 48 | Concrete | Hydroelectric | Low | 1907 |
| 37 | Rice Reservoir Dam | Sullivan | 48 | Earth | Water Supply | High | 1935 |
| 38 | Dead River Dam 1 | Coos | 47 | Earth | Flood Risk Reduction | High | 1970 |
| 39 | Chadwick Meadows Wildlife Ref Dam | Merrimack | 47 | Earth | Recreation | Significant | 1970 |
| 40 | Wolfeboro Sewage Lagoon Dam | Carroll | 45 | Earth | Other | High | 1975 |
| 41 | Cold River Site 1 Dam | Carroll | 43 | Earth | Flood Risk Reduction | High | 1969 |
| 42 | Jackman Reservoir Dam | Hillsborough | 43 | Earth | Hydroelectric | High | 1926 |
| 43 | Eastman Falls | Merrimack | 43 | Concrete | Hydroelectric | Significant | 1937 |
| 44 | Dole Reservoir Dam | Sullivan | 43 | Concrete | Water Supply | High | 1913 |
| 45 | Abeniki Lake Dam | Coos | 40 | Earth | Recreation | High | 1900 |
| 46 | Campton Pond Hydro Dam | Grafton | 39 | Concrete | Hydroelectric | High | 1890 |
| 47 | Souhegan River Site 12a North Dike | Hillsborough | 39 | Earth | Flood Risk Reduction | High | 1965 |
| 48 | Babbidge Reservoir Dam | Cheshire | 38 | Earth | Water Supply | High | 1931 |
| 49 | Gilman | Coos | 38 | Concrete | Hydroelectric | Low | 1898 |
| 50 | Souhegan River Site 12a South Dam | Hillsborough | 38 | Earth | Flood Risk Reduction | High | 1965 |