- When in Othello, Washington, you have a few options for dumping your black water and gray water from your RV.- Potholes State Park offers a dump station conveniently located within the park.- Suncrest RV Park also provides a dump station for its guests and other RV travelers passing through the area.- If you need dumping facilities, Grant County Fairgrounds has a dump station available for public use.- Another option is SunBasin RV Park, which offers a dump station along with fresh water and a hose for flushing tanks.- Remember to dispose of your RV trash in designated RV waste disposal areas.