Washington Dams
817 dams tracked by the National Inventory of Dams
Total Dams
817
High Hazard
404
49.4%
Poor / Unsatisfactory
65
Average Age
55 yrs
Hazard Classification
High404 (49.4%)
Significant98 (12.0%)
Low312 (38.2%)
Condition Assessment
Satisfactory241 (29.5%)
Fair191 (23.4%)
Poor / Unsatisfactory65 (8.0%)
Not Rated320 (39.2%)
Federal
69
State
42
Local
193
Private
392
Tallest Dams
- Grand Coulee Dam550 ft
- Ross540 ft
- Mud Mountain Dam425 ft
- Swift No. 1412 ft
- Diablo389 ft
High Hazard Dams
- Grand Coulee DamHigh
- RossHigh
- Mud Mountain DamHigh
- Swift No. 1High
- DiabloHigh
Poor Condition Dams
- Lower BakerPoor
- WellsPoor
- Van Stone Tailings DamPoor
- Indian Creek DamPoor
- Butterworth DamPoor
All Dams in Washington
Showing 501–525 of 817
| Dam Name | Height (ft) | Year | Hazard | Condition |
|---|---|---|---|---|
| North Fork Clover Creek E1 Det Basin Pierce County | 10 | 2000 | High | Fair |
| North Fork Clover Creek W1 Det Facil Pierce County | 10 | 2001 | High | Fair |
| North Ranch Storage Lagoon Mason County | 18 | 2018 | Significant | Satisfactory |
| Oak Harbor Wastewater Lagoon Nw Cell Island County | 8 | 1990 | Low | Not Rated |
| Oak Harbor Wastewater Lagoon Sw Cell Island County | 8 | 1990 | Low | Not Rated |
| Ob-3 Process Water Storage Lagoon 2 Adams County | 37 | 2021 | High | Not Rated |
| Ob-3 Warden Digester Lagoon Grant County | 21 | 2018 | High | Satisfactory |
| Ochoa Ob-3 Process Water Storage Lagoon Adams County | 32 | 2009 | High | Fair |
| Olympic Orchards Dam 1 Yakima County | 21 | 1985 | High | Poor |
| Olympic Orchards Dam 2 Yakima County | 21 | 1985 | High | Fair |
| Olympic Orchards Dam 3 Yakima County | 17 | 1985 | High | Fair |
| Olympic Orchards Dam 4 Yakima County | 12 | 1985 | High | Fair |
| Olympic Orchards Dam 5 Yakima County | 17 | 1985 | High | Satisfactory |
| Olympic View Landfill Leachate Lagoon 1 Kitsap County | 24 | 1997 | High | Satisfactory |
| Orchards Block 92 Dam Walla Walla County | 22 | 1992 | Low | Not Rated |
| Orchards Block 96 Reservoir Dam Walla Walla County | 32 | 2001 | High | Satisfactory |
| O'Sullivan Dam Grant County | 200 | 1949 | High | Not Available |
| Othello Primary Treatment Pond 1a Adams County | 27 | 1982 | Low | Not Rated |
| Othello Primary Treatment Pond 1b Adams County | 16 | 1982 | Low | Not Rated |
| Owhi Okanogan County | 12 | 1915 | High | Unsatisfactory |
| Pacific Nw Sugar CO Condensation Pond Grant County | 19 | 1998 | Low | Not Rated |
| Pacific Nw Sugar CO Sedimentation Pond Grant County | 15 | 1998 | Low | Not Rated |
| Packwood Lake Lewis County | 14 | 1964 | High | Satisfactory |
| Padden Lake Dam Whatcom County | 13 | 1933 | High | Satisfactory |
| Panther Lake Ballfield Dam King County | 15 | 1994 | High | Fair |
Data sourced from the National Inventory of Dams (NID). Hazard classification reflects potential consequences of failure, not the likelihood of failure.