Tree Top Prosser Lagoons 2 & 3, located in Benton County, Washington, are privately owned offstream reservoirs with a primary purpose that falls under the category of 'Other'.
Wind
Humidity
Built in 1991, these earth dams stand at a hydraulic height of 18 feet, with a length of 3925 feet and a storage capacity of 163 acre-feet. The lagoons cover a surface area of 14.3 acres and serve a drainage area of 2 square miles.
Managed by the Washington Department of Ecology, Tree Top Prosser Lagoons 2 & 3 have been assessed as having a fair condition, with a significant hazard potential. The last inspection in April 2016 indicated a need for continued monitoring and maintenance to ensure their structural integrity. With a five-year inspection frequency, these lagoons play a crucial role in water resource management in the region and are subject to state regulation, inspection, and enforcement to guarantee their safe operation and functionality. For water resource and climate enthusiasts, these lagoons offer a fascinating case study in private dam ownership and management within the Pacific Northwest.
Year Completed |
1991 |
Dam Length |
3925 |
River Or Stream |
Offstream |
Primary Dam Type |
Earth |
Surface Area |
14.3 |
Hydraulic Height |
18 |
Drainage Area |
2 |
Nid Storage |
163 |
Structural Height |
18 |
Hazard Potential |
Significant |
Foundations |
Soil |
Nid Height |
18 |
Yakima River At Mabton
|
28900cfs |
Yakima River At Kiona
|
23800cfs |
Granger Drain At Granger
|
13cfs |
Columbia River Below Priest Rapids Dam
|
124000cfs |
Umatilla River Near Umatilla
|
516cfs |
Yakima River Above Ahtanum Creek At Union Gap
|
14200cfs |