We stayed in the Centennial Park Campground while in Soldotna. It is located right on the Kenai River. It fills to capacity with fishermen when the run starts. It has 220 sites. There aren't any services as I recall. It is first come first served, no reservations. It was packed with fishermen when we were there. It was a very busy place. Combat camping. It is city run. Phone 907-262-5299.
During the run, campers are parked all over the place. It really gets crowded. There are several other campgrounds in the area. I don't know if they have services. We camped all summer in 2011 in Alaska and only had power a few times. State parks had just pitcher pumps for water. Grocery stores and gas stations have dumps, LP, water etc. It is the most RV friendly place to boondockers you will find anywhere. We loved being off the grid.