Hydroelectric Dams

2,099 dams in the US serve this purpose.

Dam Name	Hazard	Height	Built	Type	State
Hungry Horse Flathead	High Hazard	564 ft	1952	Concrete	Montana
Hunters Calaveras	High Hazard	59 ft	1927	Concrete	California
Huntington Falls Addison	Low Hazard	34 ft	1910	Concrete	Vermont
Hunts Pond Worcester	Low Hazard	15 ft	1936	Concrete	Massachusetts
Hyatt Jackson	High Hazard	47 ft	1921	Rockfill	Oregon
Hydro-Kennebec Kennebec	Low Hazard	35 ft	1989	Concrete	Maine
Hydro-Kennebec (Old Canal Gatehouse) Kennebec	High Hazard	28 ft	1989	Masonry	Maine
Ice Harbor Lock and Dam Walla Walla	High Hazard	—	1962	Concrete	Washington
Ice House Middlesex	Low Hazard	12 ft	1906	Other	Massachusetts
Ice House Dike No. 1 El Dorado	Significant Hazard	57 ft	—	Earth	California
Idaho Falls Upper Diversion Dam No 1 Bonneville	Low Hazard	28 ft	1982	—	Idaho
Idaho Falls Upper Powerhouse Dam No 2 Bonneville	Low Hazard	37 ft	1982	—	Idaho
Indian Falls Jefferson	Low Hazard	12 ft	1905	Gravity	New York
Indian Ole Lassen	High Hazard	26 ft	1924	Buttress	California
Indian Orchard Hampden	High Hazard	30 ft	1846	Masonry	Massachusetts
Indian Pass Ranch Dam Essex	Low Hazard	25 ft	—	Earth	New York
Indian Pond Somerset	High Hazard	175 ft	1955	Concrete	Maine
Indian Pond Somerset	Low Hazard	12 ft	1900	Rockfill	Maine
Indian Pond - East Dike Somerset	Significant Hazard	15 ft	1955	Earth	Maine
Indian Pond - West Dike Somerset	Low Hazard	10 ft	1955	Earth	Maine
Indian Valley Lake	High Hazard	207 ft	1975	Earth	California
Inghams Dam Fulton	High Hazard	125 ft	1911	Concrete	New York
International Falls Koochiching	Low Hazard	29 ft	1909	Gravity	Minnesota
Iowa Falls Milldam Hardin	Low Hazard	26 ft	1925	Gravity	Iowa
Iron Canyon Shasta	High Hazard	214 ft	1965	Earth	California
Iron Gate Siskiyou	High Hazard	173 ft	1962	Earth	California
Iroquois St. Lawrence	Significant Hazard	67 ft	1958	Concrete	New York
Irving Barry	Low Hazard	18 ft	1939	Gravity	Michigan
Isabella Dam Kern	High Hazard	98 ft	1953	Earth	California
Island Lake North Dike St. Louis	High Hazard	21 ft	1915	Earth	Minnesota
Ivy River Madison	Low Hazard	62 ft	1918	Gravity	North Carolina
Jackman Reservoir Dam Hillsborough	High Hazard	43 ft	1926	Earth	New Hampshire
Jackson Creek Amador	High Hazard	193 ft	1965	Earth	California
Jackson Creek Spillway Amador	High Hazard	37 ft	—	Earth	California
Jackson Lake Nevada	High Hazard	22 ft	1943	Earth	California
Jackson Meadows Nevada	High Hazard	196 ft	1965	Earth	California
Jackson Mills Hillsborough	Significant Hazard	33 ft	1920	Concrete	New Hampshire
James Thompson Rensselaer	Low Hazard	19 ft	1927	Concrete	New York
James W. Trimble Lock and Dam Sebastian	Significant Hazard	28 ft	1969	Concrete	Arkansas
Jay Franklin	Low Hazard	24 ft	1912	Concrete	Maine
J. Brodie Smith Coos	High Hazard	31 ft	1948	Concrete	New Hampshire
Jeffrey Dike No 1 Lincoln	Low Hazard	10 ft	1941	Earth	Nebraska
Jensen Dawson	Low Hazard	18 ft	1941	Earth	Nebraska
Jersey Lincoln	High Hazard	34 ft	1929	Gravity	Wisconsin
Jim Falls Chippewa	High Hazard	55 ft	1923	Gravity	Wisconsin
Jim Woodruff Lock and Dam Jackson	High Hazard	—	1954	Gravity	Florida
Jocassee Pickens	High Hazard	385 ft	1973	Rockfill	South Carolina
Johan Vineyard Reservoir H Polk	Low Hazard	35 ft	—	Earth	Oregon
John C Boyle Klamath	High Hazard	68 ft	1958	Gravity	Oregon
John Day Lock and Dam Klickitat	High Hazard	118 ft	1968	Earth	Oregon