
The Thompson Seeps are located approximately 11.5 miles southwest of Othello, Washington in Franklin County. Thompson Seep South has a mean depth 6 feet and a maximum depth of 14 feet, and is approximately 25 acres in size. Lake is fed from groundwater and run-off flow from the Wahluke Branch Ten Wasteway.
South Thompson Seeps is owned by the United States Bureau of Reclamation but is managed by the Washington Department of Fish and Wildlife. Primitive roads, consisting mostly of sand and gravel, lead to the lake.
Thompson Seep South provides anglers two primitive boat launch areas, both located on the west shoreline.
Species you might catch