Dams in Grant County, Washington
44Total Dams
13High Hazard
6Significant
Dam Safety in Grant County, Washington
Grant County has 44 dams tracked in the National Inventory of Dams. Of these, 13 are classified as high hazard — meaning failure would probably cause loss of human life. Another 6 carry a significant hazard classification. Currently, 2 dams have a condition assessment of poor or unsatisfactory.
The average dam in Grant County is 46 years old. The most common purpose is other. The tallest dam is O'sullivan Dam at 200 ft.
Explore more: Oldest dams in Washington · Tallest dams · High risk dams · Largest reservoirs
| Dam | Hazard | Condition | Height (ft) | Purpose | Year |
|---|---|---|---|---|---|
| O'sullivan Dam | High | Not Available | 200 | Flood Risk Reduction | 1949 |
| Priest Rapids | High | Fair | 187 | Hydroelectric | 1961 |
| North Dam | High | Not Available | 145 | Flood Risk Reduction | 1951 |
| Pinto Dam | High | Not Available | 130 | Flood Risk Reduction | 1948 |
| Dry Falls Dam | High | Not Available | 123 | Flood Risk Reduction | 1949 |
| Chiawana Frenchman Hills Dam | High | Fair | 24 | Irrigation | 1995 |
| Ob-3 Warden Digester Lagoon | High | Satisfactory | 21 | Other | 2018 |
| Koehn Ranch Reservoir | High | Satisfactory | 19 | Irrigation | 2009 |
| Chiawana Rd O Sw Pond | High | 16 | Irrigation | 2019 | |
| Lawrence Orchards Dam | High | Fair | 13 | Irrigation | 1995 |
| Partridge Ranch Dam | High | Satisfactory | 12 | Irrigation | 2010 |
| Evans Desert Aire Pond | High | Satisfactory | 9 | Irrigation | 1990 |
| Coulee City Wastewater Lagoon | High | Satisfactory | 7 | Other | 1997 |
| Quincy Sludge Storage Lagoon System Lagoons 1 2 And 3 | Significant | Fair | 15 | Other | 1986 |
| Coulee City Wastewater Lagoon Cell 4 | Significant | Satisfactory | 15 | Other | 2008 |
| Quincy Aerated Lagoon No 2 | Significant | 12 | Other | 1987 | |
| Quincy Aerated Lagoon No 1 | Significant | 12 | Other | 1987 | |
| Quincy Brine Evaporation Ponds | Significant | Fair | 11 | Other | 1989 |
| Ingredion Process Water Lagoon | Significant | Satisfactory | 9 | Other | 2000 |
| Soda Lake Dike | Low | Not Available | 59 | Irrigation | 1952 |
| Nestle Potato Effluent Lagoon | Low | 32 | Other | 1994 | |
| Port Of Moses Lake Lagoon | Low | 30 | Other | 1999 | |
| Columbia Marsh Unit #1 Dam | Low | Poor | 25 | Fish and Wildlife Pond | 1958 |
| Simplot Lrar Lagoon | Low | 24 | Other | 2006 | |
| Rec Silicon Wastewater Pond | Low | Fair | 23 | Other | 2009 |
| Moses Lake South Dam | Low | Not Available | 20 | Irrigation | 1961 |
| Pacific Nw Sugar Co Condensation Pond | Low | 19 | Other | 1998 | |
| Moses Lake North Dam | Low | 19 | Irrigation | 1930 | |
| Carnation Waste Pond No 7 | Low | 16 | Other | 1979 | |
| Pacific Nw Sugar Co Sedimentation Pond | Low | 15 | Other | 1998 | |
| Smith Brothers Dairy Storage Lagoon | Low | 15 | Other | 2001 | |
| Columbia Marsh Unit #2 Dam | Low | Fair | 15 | Fish and Wildlife Pond | 1957 |
| Lindblad Brothers Dam | Low | Fair | 14 | Flood Risk Reduction | 1940 |
| Higginbotham Reservoir Dam | Low | 13 | Irrigation | 1947 | |
| Lyon Lake Dam | Low | 13 | Recreation | 1971 | |
| Moran Slough Dike | Low | Satisfactory | 13 | Hydroelectric | 1964 |
| Columbia Marsh Unit #1 Pond No. 3 Dam | Low | Poor | 13 | Fish and Wildlife Pond | 1958 |
| Mcdonald Dam | Low | 12 | Flood Risk Reduction | 1924 | |
| Alkali Lake | Low | 12 | Recreation | 1950 | |
| Rearing Pond Dike | Low | 12 | Fish and Wildlife Pond | 1964 | |
| Crab Creek Flood Flat Water Control Structure | Low | 11 | Fish and Wildlife Pond | 2024 | |
| Merry Dam | Low | 10 | Recreation | 1976 | |
| Lenice Dam | Low | 10 | Recreation | 1976 | |
| George City Wastewater Treatment Lago | Low | 9 | Other | 1996 |