Dams in Umatilla County, Oregon
11Total Dams
3High Hazard
2Significant
Dam Safety in Umatilla County, Oregon
Umatilla County has 11 dams tracked in the National Inventory of Dams. Of these, 3 are classified as high hazard — meaning failure would probably cause loss of human life. Another 2 carry a significant hazard classification.
The average dam in Umatilla County is 70 years old. The most common purpose is other. The tallest dam is Mckay Dam at 165 ft.
Explore more: Oldest dams in Oregon · Tallest dams · High risk dams · Largest reservoirs
Data note: Hazard potential describes the consequences if a dam failed; it does not predict the likelihood of failure. Inspection, condition, and emergency-plan fields can be incomplete or delayed. Check state dam-safety officials and local emergency managers for official guidance.
| Dam | Hazard | Condition | Height (ft) | Purpose | Year |
|---|---|---|---|---|---|
| Mckay Dam | High | Not Available | 165 | Flood Risk Reduction | 1927 |
| Cold Springs Dam | High | Not Available | 115 | Irrigation | 1908 |
| Indian Lake | High | Fair | 56 | Recreation | 1969 |
| Simplot Waste Lagoon #1 | Significant | Not Rated | 46 | Other | |
| Meacham Lake Dam | Significant | Not Rated | 14 | Other | |
| Walchli Reservoir | Low | Not Rated | 32 | Irrigation | 1980 |
| Simplot Hermiston #2 (lagoon) | Low | Not Rated | 32 | Other | 2002 |
| Three Mile Falls Diversion | Low | Not Available | 28 | Irrigation | 1913 |
| Weston Eda Wwt Lagoon | Low | Not Rated | 19 | Other | 1986 |
| Langdon Lake Dam | Low | Not Rated | 14 | Recreation | 1930 |
| Milton-freewater Lagoon N-3 | Low | Not Rated | 12 | Other | 1988 |