Beacon Hill Reservoir
Beacon Hill Reservoir is a rockfill dam located in Grays Harbor County, Washington, built in 1935. It carries a High hazard potential classification and has a poor condition assessment.
About Beacon Hill Reservoir
The primary purpose of Beacon Hill 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 Hoquiam City (local government). It impounds the Hoquiam River - Offstream near Hoquiam.
The dam stands 30 feet tall and stretches 420 feet across, and has a maximum storage capacity of 14 acre-feet. Completed in 1935, the structure is well-established, with more than 75 years of service.
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 poor, meaning the dam has recognized safety deficiencies that require remediation to address risks. An emergency action plan is in place for this dam. The most recent inspection on record was 06/28/2023.
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 Washington 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 | Washington |
| County | Grays Harbor |
| Nearest City | Hoquiam |
| River/Stream | Hoquiam River - Offstream |
| Coordinates | 46.97942, -123.87638 |
Physical Characteristics
| Dam Type | Rockfill |
| NID Height | 30 ft |
| Dam Length | 420 ft |
| Year Completed | 1935 (91 years old) |
Storage & Hydraulics
| NID Storage | 14 acre-ft |
| Max Storage | 14 acre-ft |
| Normal Storage | 10 acre-ft |
Ownership & Safety
| Purpose | Water Supply |
| Owner | Hoquiam City |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Poor |
| Last Inspection | 06/28/2023 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WA01790 |
| Federal ID | WA01790 |
| More Info | State Dam Safety Program |