Piiholo 50 Mg Reservoir
Piiholo 50 Mg Reservoir is an earth dam located in Maui County, Hawaii, built in 1971. It carries a High hazard potential classification and has a unsatisfactory condition assessment.
About Piiholo 50 Mg Reservoir
The primary purpose of Piiholo 50 Mg Reservoir is water supply. The dam stores water for municipal, industrial, or agricultural use, helping ensure a reliable supply for the surrounding area. The dam is owned by Maui County, Dept Of Water Supply (local government). It impounds the Tr-miliko Gulch Offstream near Kokomo.
The dam stands 42 feet tall and stretches 1,700 feet across, creates a reservoir covering 7 acres, has a maximum storage capacity of 166 acre-feet, and collects water from a drainage area of 0 square miles. Completed in 1971, the structure is well into its service life at over 50 years old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated unsatisfactory, indicating serious safety deficiencies exist that require immediate attention or remedial action. An emergency action plan is in place for this dam. The most recent inspection on record was 05/08/2025.
At 42 feet, this dam is taller than 89% of dams nationwide.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Hawaii dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | Hawaii |
| County | Maui |
| Nearest City | Kokomo |
| River/Stream | Tr-miliko Gulch Offstream |
| Coordinates | 20.83003, -156.27371 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 42 ft |
| Dam Height | 42 ft |
| Dam Length | 1,700 ft |
| Year Completed | 1971 (55 years old) |
Storage & Hydraulics
| NID Storage | 166 acre-ft |
| Max Storage | 166 acre-ft |
| Normal Storage | 162 acre-ft |
| Surface Area | 7 acres |
| Drainage Area | 0 sq mi |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Maui County, Dept of Water Supply |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Unsatisfactory |
| Last Inspection | 05/08/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | HI00047 |
| Federal ID | HI00047 |
| More Info | State Dam Safety Program |