Dams in New Hampshire

%!s(int=664)Total Dams

162High Hazard

185Significant

300Low Hazard

Dam Safety in New Hampshire

New Hampshire has 664 dams tracked in the National Inventory of Dams. Of these, 162 (24%) are classified as high hazard — meaning failure would probably cause loss of human life — and 185 are classified as significant hazard. Currently, 152 dams in the state have a condition assessment of poor or unsatisfactory, indicating recognized safety deficiencies.

The average dam in New Hampshire is 99 years old. Many of these aging structures were built before modern dam safety standards were established, which increases the importance of regular inspections and maintenance. The most common purpose for dams in New Hampshire is recreation, accounting for 380 of the state's dams.

Use the search above to find dams near any address in New Hampshire, or browse by county below. Each dam listing includes its hazard potential classification, condition assessment, physical characteristics, and inspection history from the NID.

New Hampshire Dam Facts

Total Dams	664
High Hazard Dams	162
Average Dam Age	99 years
Tallest Dam	170 ft
Largest Reservoir	223,722 acre-ft
Poor/Unsatisfactory Condition	152

Notable Dams in New Hampshire

Comerford170 ftHigh Moore149 ftHigh Otter Brook Dam119 ftHigh Franklin Falls Dam116 ftHigh Everett Dam115 ftHigh

Counties in New Hampshire

Belknap36 dams8 high hazard Carroll35 dams10 high hazard Cheshire89 dams22 high hazard Coos60 dams10 high hazard Grafton82 dams26 high hazard Hillsborough105 dams37 high hazard Merrimack89 dams18 high hazard Rockingham75 dams11 high hazard Strafford51 dams13 high hazard Sullivan42 dams7 high hazard

High Hazard Dams in New Hampshire

Dam	County	Height	Condition	Purpose
Comerford	Grafton	170 ft	Satisfactory	Hydroelectric
Moore	Grafton	149 ft	Satisfactory	Hydroelectric
Otter Brook Dam	Cheshire	119 ft	Not Available	Flood Risk Reduction
Franklin Falls Dam	Merrimack	116 ft	Not Available	Flood Risk Reduction
Everett Dam	Hillsborough	115 ft	Not Available	Flood Risk Reduction
Murphy Dam	Coos	106 ft	Not Rated	Recreation
Whitewater Brook Dam	Sullivan	95 ft	Fair	Water Supply
Surry Mountain Dam	Cheshire	83 ft	Not Available	Flood Risk Reduction
Souhegan River Site 26 Dam	Hillsborough	79 ft	Fair	Flood Risk Reduction
Hopkinton Dam - Dike H-2	Merrimack	77 ft	Not Available	Flood Risk Reduction
Blackwater Dam	Merrimack	75 ft	Not Available	Flood Risk Reduction
Souhegan River Site 25b Dam	Hillsborough	74 ft	Fair	Flood Risk Reduction
Hopkinton Dam	Merrimack	71 ft	Not Available	Flood Risk Reduction
Baker River Site 2 Dam	Grafton	68 ft	Fair	Flood Risk Reduction
Baker River Site 6a Dam	Grafton	68 ft	Poor	Flood Risk Reduction
Gregg Falls	Hillsborough	66 ft	Satisfactory	Hydroelectric
Hopkinton Dam - Dike H-3	Merrimack	66 ft	Not Available	Flood Risk Reduction
Minnewawa	Cheshire	63 ft	Satisfactory	Hydroelectric
Baker River Site 8 Dam	Grafton	63 ft	Satisfactory	Flood Risk Reduction
Edward Macdowell Dam	Hillsborough	63 ft	Not Available	Flood Risk Reduction
Gunnison Lake Site D2 Dam	Sullivan	62 ft	Fair	Flood Risk Reduction
Wilder	Grafton	59 ft	Satisfactory	Hydroelectric
Souhegan River Site 10a Dam	Hillsborough	59 ft	Satisfactory	Flood Risk Reduction
Cascade	Coos	57 ft	Fair	Hydroelectric
First Connecticut Lake Dam	Coos	56 ft	Fair	Hydroelectric
Arlington Mills Res Wheeler Dam	Rockingham	54 ft	Satisfactory	Water Supply
Baker River Site 5 Dam	Grafton	53 ft	Poor	Flood Risk Reduction
Oliverian Dam	Grafton	52 ft	Satisfactory	Flood Risk Reduction
Everett Dam - Dike P-1	Hillsborough	50 ft	Not Available	Flood Risk Reduction
Rice Reservoir Dam	Sullivan	48 ft	Satisfactory	Water Supply
Dead River Dam 1	Coos	47 ft	Fair	Flood Risk Reduction
Wolfeboro Sewage Lagoon Dam	Carroll	45 ft	Fair	Other
Dole Reservoir Dam	Sullivan	43 ft	Fair	Water Supply
Cold River Site 1 Dam	Carroll	43 ft	Satisfactory	Flood Risk Reduction
Jackman Reservoir Dam	Hillsborough	43 ft	Poor	Hydroelectric
Abeniki Lake Dam	Coos	40 ft	Satisfactory	Recreation
Campton Pond Hydro Dam	Grafton	39 ft	Fair	Hydroelectric
Souhegan River Site 12a North Dike	Hillsborough	39 ft	Fair	Flood Risk Reduction
Babbidge Reservoir Dam	Cheshire	38 ft	Satisfactory	Water Supply
Souhegan River Site 12a South Dam	Hillsborough	38 ft	Fair	Flood Risk Reduction
Blackwater Dam - Little Hill Dike	Merrimack	38 ft	Not Available	Flood Risk Reduction
Souhegan River Site 19 Dam	Hillsborough	36 ft	Fair	Flood Risk Reduction
Bellamy Reservoir Dam	Strafford	35 ft	Satisfactory	Water Supply
Eastman Lake Dam	Sullivan	35 ft	Satisfactory	Recreation
Tower Hill Pond Dam	Rockingham	35 ft	Satisfactory	Water Supply
Harris Pond Dam	Hillsborough	35 ft	Satisfactory	Water Supply
Lake Gloriette Dike	Coos	34 ft	Poor	Recreation
Weare Reservoir Dam	Hillsborough	34 ft	Poor	Recreation
Pisgah Reservoir Dam	Cheshire	33 ft	Poor	Recreation
Lake Gloriette Dam	Coos	33 ft	Poor	Recreation
Lower Reservoir Dam	Grafton	33 ft	Fair	Water Supply
Mendums Pond Dam	Rockingham	31 ft	Poor	Recreation
Goose Pond Dam	Grafton	31 ft	Poor	Recreation
Goffstown Upper Reservoir Dam	Hillsborough	31 ft	Poor	Water Supply
J. Brodie Smith	Coos	31 ft	Satisfactory	Hydroelectric
Kelley's Falls Dam	Hillsborough	31 ft	Poor	Hydroelectric
Seaver Reservoir Dam	Cheshire	30 ft	Satisfactory	Recreation
Goffstown Lower Reservoir Dam	Hillsborough	30 ft	Fair	Water Supply
Howe Reservoir Dam	Cheshire	30 ft	Fair	Recreation
Upper Reservoir Dam	Grafton	30 ft	Fair	Water Supply
Massabesic Lake Dam	Hillsborough	30 ft	Satisfactory	Water Supply
Hanover Center Reservoir Dam	Grafton	30 ft	Satisfactory	Water Supply
Souhegan River Site 35 Dam	Hillsborough	30 ft	Fair	Flood Risk Reduction
Everett Dam - Dike P-2	Hillsborough	30 ft	Not Available	Flood Risk Reduction
China Mill Dam	Merrimack	29 ft	Fair	Hydroelectric
Amoskeag	Hillsborough	29 ft	Fair	Hydroelectric
Souhegan River Site 28 Dam	Hillsborough	29 ft	Satisfactory	Flood Risk Reduction
Pawtuckaway Lake Dollof Dam	Rockingham	28 ft	Poor	Recreation
Supply Pond Dam	Hillsborough	28 ft	Fair	Water Supply
Souhegan Site 14 Dam	Hillsborough	28 ft	Fair	Flood Risk Reduction
Macallen Dam	Rockingham	27 ft	Satisfactory	Recreation
Hoods Pond Dam	Rockingham	27 ft	Satisfactory	Recreation
Rochester Reservoir Dam	Strafford	26 ft	Satisfactory	Water Supply
Deering Reservoir Dam	Hillsborough	25 ft	Satisfactory	Recreation
Bowers Dam	Hillsborough	25 ft	Poor	Water Supply
Verney Mill Hydro Dam	Hillsborough	25 ft	Not Rated	Hydroelectric
Souhegan Site 8 Dam	Hillsborough	25 ft	Satisfactory	Flood Risk Reduction
Cross Power	Coos	25 ft	Satisfactory	Hydroelectric
Bow Lake Dam	Strafford	24 ft	Poor	Recreation
New Wilton Reservoir Dam	Hillsborough	24 ft	Poor	Recreation
Baker River Site 11 Dam	Grafton	24 ft	Poor	Flood Risk Reduction
Baker River Site 11a Dam	Grafton	24 ft	Satisfactory	Flood Risk Reduction
Merrymeeting Lake Dam	Strafford	22 ft	Poor	Recreation
Woodward Pond Dam	Cheshire	22 ft	Satisfactory	Water Supply
Rivermill Mascoma Hydro Dam	Grafton	22 ft	Poor	Hydroelectric
Goose Pond Dam	Cheshire	22 ft	Satisfactory	Recreation
Jones Dam	Strafford	21 ft	Poor	Recreation
Pittsfield Mill Dam	Merrimack	21 ft	Poor	Recreation
Souhegan River Site 33 Dam	Hillsborough	21 ft	Fair	Flood Risk Reduction
Millville Lake Dam	Rockingham	20 ft	Poor	Recreation
Walpole Reservoir Dam	Cheshire	20 ft	Poor	Water Supply
Dells Pond Outlet Dam	Grafton	20 ft	Poor	Recreation
Three Mile Reservoir Dam	Cheshire	20 ft	Satisfactory	Flood Risk Reduction
Sawyer Lake Dam	Belknap	19 ft	Poor	Recreation
Taylor River Pond Dam	Rockingham	19 ft	Satisfactory	Fish and Wildlife Pond
Jones Pond Dam	Strafford	19 ft	Satisfactory	Recreation
Milton Three Ponds Dam	Strafford	19 ft	Poor	Recreation
Sunrise Lake Dam	Strafford	19 ft	Satisfactory	Recreation
Cheshire Mills Lower Dam	Cheshire	18 ft	Poor	Hydroelectric
Berry Pond Dam	Merrimack	18 ft	Satisfactory	Water Supply