Dams in Hawaii

124Total Dams

117High Hazard

2Significant

5Low Hazard

Dam Safety in Hawaii

Hawaii has 124 dams tracked in the National Inventory of Dams. Of these, 117 (94%) are classified as high hazard — meaning failure would probably cause loss of human life — and 2 are classified as significant hazard. Currently, 95 dams in the state have a condition assessment of poor or unsatisfactory, indicating recognized safety deficiencies.

The average dam in Hawaii is 92 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 Hawaii is irrigation, accounting for 94 of the state's dams.

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

Hawaii Dam Facts

Total Dams	124
High Hazard Dams	117
Average Dam Age	92 years
Tallest Dam	141 ft
Largest Reservoir	9,900 acre-ft
Poor/Unsatisfactory Condition	95

Notable Dams in Hawaii

Alexander141 ftHigh Puu Lua Reservoir110 ftHigh Wahiawa Dam98 ftHigh Ku Tree Reservoir90 ftHigh Kaneohe Dam83 ftHigh

Explore Hawaii Dams

Oldest DamsEarliest dams in Hawaii Tallest DamsHighest dams in Hawaii

Counties in Hawaii

Hawaii10 dams9 high hazard Honolulu13 dams12 high hazard Kauai47 dams45 high hazard Maui54 dams51 high hazard

High Hazard Dams in Hawaii

Dam	County	Height	Condition	Purpose
Alexander	Kauai	141 ft	Fair	Hydroelectric
Puu Lua Reservoir	Kauai	110 ft	Unsatisfactory	Fish and Wildlife Pond
Wahiawa Dam	Honolulu	98 ft	Poor	Irrigation
Ku Tree Reservoir	Honolulu	90 ft	Unsatisfactory	Other
Kaneohe Dam	Honolulu	83 ft	Fair	Flood Risk Reduction
Aepo Reservoir	Kauai	74 ft	Fair	Irrigation
Nuuanu Dam No. 4	Honolulu	73 ft	Fair	Flood Risk Reduction
Opaeula 01 Reservoir	Honolulu	71 ft	Fair	Irrigation
Horner Reservoir	Maui	70 ft	Poor	Irrigation
Mimino Reservoir	Kauai	69 ft	Poor	Irrigation
Waimanalo 60 Mg Reservoir	Honolulu	65 ft	Fair	Irrigation
Waikoloi Reservoir	Kauai	64 ft	Poor	Irrigation
Kahoma Reservoir	Maui	60 ft	Poor	Irrigation
Kualapuu Reservoir	Maui	58 ft	Fair	Irrigation
Kahana Nui Dam	Maui	58 ft	Poor	Flood Risk Reduction
Piwai Reservoir	Kauai	56 ft	Poor	Irrigation
Kahakapao Reservoirs	Maui	54 ft	Poor	Water Supply
Waikoloa Reservoir No. 3	Hawaii	54 ft	Fair	Water Supply
Kapaia Reservoir	Kauai	53 ft	Poor	Irrigation
Wailuku Water Reservoir 10	Maui	52 ft	Unsatisfactory	Irrigation
Waimea 60 Mg Reservoir	Hawaii	52 ft	Poor	Irrigation
Kaneha Reservoir	Kauai	51 ft	Poor	Irrigation
Upper Helemano Reservoir	Honolulu	51 ft	Poor	Irrigation
Kaupale Reservoir	Kauai	50 ft	Poor	Irrigation
Ipuolono Reservoir	Kauai	50 ft	Poor	Irrigation
Honokowai - Structure #8	Maui	50 ft	Fair	Flood Risk Reduction
Twin Reservoirs	Kauai	49 ft	Unsatisfactory	Other
Papuaa Reservoir	Kauai	48 ft	Poor	Irrigation
Kumano Reservoir	Kauai	48 ft	Poor	Irrigation
Huinawai Reservoir	Kauai	47 ft	Poor	Irrigation
Pauwela Reservoir	Maui	47 ft	Poor	Irrigation
Maui Reservoir 40	Maui	47 ft	Fair	Irrigation
Kaloko Reservoir	Kauai	46 ft	Poor	Irrigation
Manuhonuhonu Reservoir	Kauai	45 ft	Poor	Irrigation
Peahi Reservoir	Maui	45 ft	Poor	Irrigation
Waikoloa Reservoir No. 1	Hawaii	44 ft	Poor	Water Supply
Haiku Reservoir	Maui	43 ft	Unsatisfactory	Irrigation
Napili 2-3 Desilting Basin	Maui	43 ft	Fair	Flood Risk Reduction
Aepoeha Reservoir	Kauai	42 ft	Fair	Irrigation
Olinda Reservoir	Maui	42 ft	Poor	Water Supply
Piiholo 50 Mg Reservoir	Maui	42 ft	Unsatisfactory	Water Supply
Maui Reservoir 20	Maui	42 ft	Poor	Irrigation
Halenanahu Reservoir	Kauai	40 ft	Unsatisfactory	Irrigation
Aepoekolu Reservoir	Kauai	40 ft	Poor	Irrigation
Kepani Reservoir	Kauai	40 ft	Poor	Irrigation
Pa Aalii Reservoir	Hawaii	40 ft	Fair	Other
Maui Reservoir 24	Maui	39 ft	Poor	Irrigation
Maui Reservoir 15	Maui	39 ft	Poor	Irrigation
Punawai Reservoir	Hawaii	38 ft	Fair	Irrigation
Helemano 6 Reservoir	Honolulu	38 ft	Poor	Irrigation
Mau Reservoir	Kauai	38 ft	Poor	Irrigation
Upper Field 14 Reservoir	Maui	38 ft	Poor	Irrigation
Aahoaka Reservoir	Kauai	38 ft	Poor	Irrigation
Elima Reservoir	Kauai	37 ft	Poor	Irrigation
Papaaea Reservoir	Maui	37 ft	Poor	Irrigation
Puu Koa Reservoir	Maui	37 ft	Poor	Irrigation
Middle Field 14 Reservoir	Maui	36 ft	Unsatisfactory	Irrigation
Hukiwai Reservoir	Kauai	36 ft	Poor	Irrigation
Aepoalua Reservoir	Kauai	35 ft	Poor	Irrigation
Maui Reservoir 33	Maui	35 ft	Poor	Irrigation
Waikoloa Reservoir No. 2	Hawaii	35 ft	Fair	Water Supply
Reservoir 140	Maui	35 ft	Poor	Irrigation
Nuuanu Reservoir No. 1	Honolulu	34 ft	Poor	Flood Risk Reduction
Paauilo Reservoir	Hawaii	34 ft	Poor	Irrigation
Elua Reservoir	Kauai	34 ft	Poor	Irrigation
Wailua Reservoir	Kauai	34 ft	Fair	Irrigation
Mahinahina Reservoir	Maui	34 ft	Poor	Water Supply
Wailuku Water Reservoir 6	Maui	33 ft	Fair	Irrigation
Puu O Hewa Reservoir	Kauai	33 ft	Poor	Irrigation
Pond No. 1 At Kauai Ranch	Kauai	32 ft	Fair	Irrigation
Omao Reservoir	Kauai	32 ft	Unsatisfactory	Irrigation
Plantation Reservoir	Maui	31 ft	Fair	Irrigation
Honokowai Reservoir	Maui	31 ft	Poor	Irrigation
Maui Reservoir 14	Maui	31 ft	Unsatisfactory	Irrigation
Waikaia Reservoir	Kauai	30 ft	Poor	Irrigation
Hanakaoo Reservoir	Maui	30 ft	Fair	Irrigation
Kaopala Basin	Maui	30 ft	Fair	Flood Risk Reduction
Maui Reservoir 22	Maui	30 ft	Fair	Irrigation
Kehalani Offsite Retention Basin	Maui	30 ft	Poor	Flood Risk Reduction
Okinawa Reservoir	Kauai	29 ft	Poor	Irrigation
Maui Reservoir 84	Maui	29 ft	Poor	Irrigation
Maui Reservoir 80	Maui	29 ft	Fair	Irrigation
Waita Reservoir	Kauai	28 ft	Poor	Irrigation
Maui Reservoir 30	Maui	28 ft	Poor	Irrigation
Maui Reservoir 74	Maui	28 ft	Poor	Irrigation
Pinau Reservoir	Kauai	28 ft	Unsatisfactory	Other
Maunaolu Reservoir	Honolulu	27 ft	Fair	Irrigation
Maui Reservoir 42	Maui	27 ft	Poor	Irrigation
Halaula Reservoir	Kauai	26 ft	Poor	Irrigation
Kaawanui Reservoir	Kauai	26 ft	Poor	Irrigation
Aii Reservoir	Kauai	26 ft	Poor	Irrigation
Kaili Ili Reservoir	Maui	25 ft	Fair	Irrigation
Maui Field 290 Reservoir	Maui	25 ft	Poor	Irrigation
Mana Reservoir	Kauai	25 ft	Unsatisfactory	Irrigation
Kemoo 5 Reservoir	Honolulu	25 ft	Poor	Irrigation
Kalihiwai Reservoir	Kauai	25 ft	Poor	Irrigation
Oahu Reservoir 155	Honolulu	25 ft	Poor	Irrigation
Maui Reservoir 60	Maui	25 ft	Poor	Irrigation
Maui Reservoir 73	Maui	25 ft	Poor	Irrigation
Kapa Reservoir	Kauai	24 ft	Poor	Irrigation