We recently stayed at Tucannon River RV Park near Starbuck...hookups, showers, quiet environment, friendly staff, and it's on the way from Umatilla...Google for phone #. Does Steptoe Butte have what you are looking for? It's been years since I've been there...just asking.
Pullman P & R has a campground along the Palouse in town with full hookups which we have used during football season. Google City of Pullman/Parks and Rec.
2011 Chevy 2500 Duramax diesel
2019 Timber Ridge 24RLS (Outdoors RV)
Go Cougs!