Lewis and Clark at Gavins Point Dam in Yankton?

When we go for a week we usually stay at COE Howell Station in Pella (red rock) iowa. It's along the desmoines river and has nice flat bike trails for the hill impaired and my husband loves to bow fish along the river. The park is nice, lots of space between campers and good people running it. But we were thinking we would try the Gavins Point area. Has anyone been there camping? Is it roomy, cuz i hate to be packed in like sardines and worrying someone would damage my new WC.