- In Holdrege, Nebraska, there are several convenient RV dump stations available for your black water and gray water needs.- Dump stations can be found at Adams County Fairgrounds, Hastings Campground and RV Park, George H Clayton Rest Area, Hall County Park, and KOA Grand Island KOA Campground.- These dump stations provide fresh water for flushing tanks and have designated areas for RV waste disposal.- Remember to bring your own hose for flushing tanks and dispose of trash properly in the RV trash bins provided at the dump stations.