Wenas Dam
Wenas Dam is a rockfill dam located in Yakima County, Washington, built in 1911. It carries a High hazard potential classification and has a fair condition assessment.
About Wenas Dam
The primary purpose of Wenas Dam is irrigation. The dam stores and diverts water for agricultural irrigation, supporting farming operations in the surrounding area. The dam is owned by Wenas Irrigation District (public utility). It impounds the Wenas Creek near Selah.
The dam stands 90 feet tall and stretches 525 feet across, creates a reservoir covering 142 acres, has a maximum storage capacity of 5,500 acre-feet, and collects water from a drainage area of 114 square miles. Completed in 1911, the structure is over a century 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 fair — the dam has minor deficiencies that are being addressed or do not pose an immediate safety threat. An emergency action plan is in place for this dam. The most recent inspection on record was 10/17/2022.
At 90 feet, this dam is taller than 98% of all dams in the United States.
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 | Yakima |
| Nearest City | Selah |
| River/Stream | Wenas Creek |
| Coordinates | 46.81426, -120.67201 |
Physical Characteristics
| Dam Type | Rockfill |
| NID Height | 90 ft |
| Dam Length | 525 ft |
| Year Completed | 1911 (115 years old) |
Storage & Hydraulics
| NID Storage | 5,500 acre-ft |
| Max Storage | 5,500 acre-ft |
| Normal Storage | 3,200 acre-ft |
| Surface Area | 142 acres |
| Drainage Area | 114 sq mi |
| Max Discharge | 29,000 cfs |
Ownership & Safety
| Purpose | Irrigation |
| Owner | Wenas Irrigation District |
| Owner Type | Public Utility |
| Hazard Classification | High |
| Condition Assessment | Fair |
| Last Inspection | 10/17/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | WA00002 |
| Federal ID | WA00002 |
| More Info | State Dam Safety Program |