High Risk Dams in the United States

There are 2,631 high hazard dams in the United States with a condition assessment of poor or unsatisfactory. These are dams where failure would probably cause loss of life, and where recognized safety deficiencies have been identified.

A "poor" condition means a safety deficiency exists but has been addressed with temporary risk reduction measures. "Unsatisfactory" means a deficiency requires immediate attention. Combined with a high hazard classification, these dams represent the most pressing dam safety concerns in the country.

Of the 16,265 high hazard dams nationwide, 2,631 (16%) have a condition rating of poor or unsatisfactory.

High Risk Dams by State

State	High Risk Dams	Poor	Unsatisfactory
North Carolina	235	197	38
Georgia	189	186	3
Texas	182	89	93
South Carolina	156	142	14
Pennsylvania	145	134	11
Mississippi	140	81	59
Ohio	132	128	4
New Mexico	115	109	6
Kentucky	104	89	15
New York	103	97	6
Indiana	91	89	2
Hawaii	88	75	13
Kansas	75	74	1
New Hampshire	57	57	0
New Jersey	56	56	0
Washington	52	47	5
Virginia	52	44	8
California	47	44	3
Massachusetts	46	36	10
West Virginia	41	40	1
Montana	38	30	8
Oklahoma	37	28	9
Colorado	37	0	37
Missouri	35	1	34
Rhode Island	34	34	0
Arizona	34	26	8
Maryland	33	24	9
Oregon	30	18	12
Nevada	26	22	4
South Dakota	23	16	7
Arkansas	22	22	0
Vermont	20	19	1
Maine	19	8	11
Michigan	18	14	4
Connecticut	17	17	0
Wyoming	14	12	2
Puerto Rico	12	10	2
Nebraska	12	12	0
North Dakota	12	12	0
Utah	10	10	0
Florida	10	3	7
Wisconsin	7	3	4
Iowa	5	5	0
Louisiana	4	2	2
Alaska	4	4	0
Tennessee	3	1	2
Idaho	3	2	1
Delaware	3	3	0
Alabama	2	1	1
Minnesota	1	1	0

Largest High Risk Dams

The following are the tallest high hazard dams with poor or unsatisfactory condition ratings:

Dam	State	County	Height (ft)	Condition	Purpose
Mossyrock	Washington	Lewis	606	Unsatisfactory	Hydroelectric
Castaic	California	Los Angeles	340	Poor	Water Supply
Amistad Dam	Texas	Val Verde	287	Poor	Flood Risk Reduction
Lower Baker	Washington	Skagit	285	Poor	Hydroelectric
Nacimiento	California	San Luis Obispo	255	Poor	Hydroelectric
Mayfield	Washington	Lewis	250	Unsatisfactory	Hydroelectric
Anderson	California	Santa Clara	240	Unsatisfactory	Water Supply
El Capitan	California	San Diego	237	Poor	Water Supply
Smith	Oregon	Linn	235	Unsatisfactory	Hydroelectric
Santeetlah	North Carolina	Graham	216	Poor	Hydroelectric
Santa Felicia	California	Ventura	213	Poor	Water Supply
Fletcher Tailings Dam	Missouri	Reynolds	201	Unsatisfactory	Tailings
Garzas Dam	Puerto Rico	Adjuntas	201	Unsatisfactory	Hydroelectric
Guayo Dam	Puerto Rico	Adjuntas	190	Poor	Hydroelectric
Waterbury	Vermont	Washington	187	Poor	Flood Risk Reduction
Morena	California	San Diego	181	Poor	Water Supply
Round Valley South Dam	New Jersey	Hunterdon	178	Poor	Water Supply
Liberty Dam	Maryland	Baltimore	175	Unsatisfactory	Water Supply
Bath County P S Lower Reservoir - Lower Dam	Virginia	Bath	170	Poor	Hydroelectric
Vermilion Valley	California	Fresno	165	Poor	Hydroelectric
Matilija	California	Ventura	163	Poor	Other
Barrett	California	San Diego	161	Poor	Water Supply
Wells	Washington	Chelan	160	Poor	Hydroelectric
Kootenai Dvlpmnt Impoundment Dam	Montana	Lincoln	151	Poor	Other
Bartletts Ferry, Main Dam	Georgia	Harris	150	Poor	Hydroelectric
Savage	California	San Diego	149	Poor	Water Supply
Lake Fordyce	California	Nevada	145	Poor	Hydroelectric
West Fork Bitterroot (painted Rocks)	Montana	Ravalli	143	Poor	Irrigation
Guadalupe	California	Santa Clara	142	Poor	Water Supply
Logan Martin	Alabama	St. Clair	142	Poor	Hydroelectric
Coyote	California	Santa Clara	140	Poor	Water Supply
Relief	California	Tuolumne	140	Poor	Hydroelectric
Sanchez	Colorado	Costilla	137	Unsatisfactory	Irrigation
Santiago Creek	California	Orange	136	Poor	Water Supply
Tabeaud	California	Amador	136	Poor	Hydroelectric
Round Valley North Dam	New Jersey	Hunterdon	135	Poor	Water Supply
Laprele	Wyoming	Converse	135	Unsatisfactory	Irrigation
Elgo	Arizona	Graham	133	Poor	Recreation
Lake Hodges	California	San Diego	131	Unsatisfactory	Water Supply
Newlan Creek Dam	Montana	Meagher	131	Poor	Irrigation
Hubbart	Montana	Flathead	130	Poor	Irrigation
Guayabal Dam	Puerto Rico	Villalba	130	Poor	Irrigation
Comerio Ii Dam	Puerto Rico	Comerío	128	Poor	Hydroelectric
Mcclure Dam	New Mexico	Santa Fe	128	Poor	Water Supply
Patillas Dam	Puerto Rico	Patillas	127	Poor	Hydroelectric
Inghams Dam	New York	Fulton	125	Poor	Hydroelectric
Cannon Creek Dam	Kentucky	Bell	125	Poor	Water Supply
Lake Mission Viejo	California	Orange	123	Poor	Water Supply
Cat Creek	Nevada	Mineral	123	Unsatisfactory	Water Supply
Matrullas Dam	Puerto Rico	Orocovis	120	Unsatisfactory	Hydroelectric
Guajataca Dam	Puerto Rico	Isabela	120	Poor	Hydroelectric
Cranks Creek Lake Dam	Kentucky	Harlan	120	Poor	Recreation
T Or C Site 8c Dam	New Mexico	Sierra	119	Poor	Flood Risk Reduction
Druid Hill Lake Reservoir And Storage Tanks	Maryland	Baltimore City	118	Poor	Water Supply
Guineo Dam	Puerto Rico	Orocovis	115	Poor	Hydroelectric
Narraguinnep - Main Dam	Colorado	Montezuma	114	Unsatisfactory	Irrigation
Hosler (reeder Gulch	Oregon	Jackson	114	Unsatisfactory	Water Supply
Little Pine Creek	Pennsylvania	Lycoming	113	Poor	Flood Risk Reduction
Almaden	California	Santa Clara	110	Poor	Other
Puu Lua Reservoir	Hawaii	Kauai	110	Unsatisfactory	Fish and Wildlife Pond
Willow Creek 3 (malheur)	Oregon	Malheur	110	Unsatisfactory	Irrigation
Lake Maloya Dam	New Mexico	Colfax	110	Poor	Water Supply
Clear Branch	Oregon	Hood River	110	Unsatisfactory	Irrigation
Beaver Lake Dam	Nebraska	Cass	108	Poor	Recreation
Lake Curry	California	Napa	107	Poor	Other
Mountain Dell	Utah	Salt Lake	105	Poor	Water Supply
Willow Creek Dam	Montana	Madison	105	Poor	Irrigation
North Fork	Pennsylvania	Somerset	105	Poor	Water Supply
Dehart	Pennsylvania	Dauphin	105	Poor	Water Supply
Carite Dam	Puerto Rico	Guayama	104	Poor	Hydroelectric
Green Canyon Dam	New Mexico	Sierra	104	Poor	Flood Risk Reduction
Pilarcitos	California	San Mateo	103	Poor	Water Supply
Magalia	California	Butte	103	Poor	Water Supply
Toronto	New York	Sullivan	103	Unsatisfactory	Hydroelectric
Cooney	Montana	Carbon	102	Poor	Irrigation
Birch Creek No. 2	Utah	Rich	101	Poor	Irrigation
Tara Lake Dam	Georgia	Carroll	101	Poor	Recreation
North Fork	California	Santa Clara	100	Poor	Water Supply
Mill Run	Pennsylvania	Blair	100	Poor	Water Supply
Moss Lake Dam	North Carolina	Cleveland	99	Poor	Water Supply
Bear Canyon Dam	New Mexico	Grant	99	Poor	Irrigation
Crow	Montana	Lake	99	Poor	Irrigation
Upper Van Tassell	Wyoming	Laramie	98	Poor	Water Supply
Wahiawa Dam	Hawaii	Honolulu	98	Poor	Irrigation
Rocky Gap Dam	Maryland	Allegany	98	Poor	Water Supply
Cliffside Inactive Ash Basin #5 Main Dam	North Carolina	Rutherford	97	Unsatisfactory	Other
Williamson Dam	Texas	Eastland	96	Unsatisfactory	Water Supply
Misselbeck	California	Shasta	96	Poor	Other
Lake Ellsworth	Oklahoma	Comanche	96	Unsatisfactory	Water Supply
Lower Willow Creek Dam	Montana	Granite	96	Poor	Irrigation
Senator Young Dam	North Dakota	Cavalier	96	Poor	Flood Risk Reduction
Bear Creek	Oregon	Clatsop	94	Poor	Water Supply
Upper Rio Hondo Site No. 1 Dam	New Mexico	Lincoln	94	Poor	Flood Risk Reduction
Spruce Run Reservoir Dam	New Jersey	Hunterdon	93	Poor	Water Supply
Sebastian Martin Site 6 Dam	New Mexico	Rio Arriba	93	Poor	Flood Risk Reduction
Fish Creek	Idaho	Blaine	92	Poor	Irrigation
Woodrat Knob	Oregon	Jackson	92	Unsatisfactory	Irrigation
Eagle Creek Reservoir Dam	Indiana	Marion	92	Poor	Flood Risk Reduction
Apple Valley Lake Dam	Ohio	Knox	91	Poor	Recreation
Talking Rock Creek Ws Str # 13	Georgia	Pickens	91	Poor	Flood Risk Reduction