Re: area off of I-55?
go down the road a bit toward wilmington. stop at the milliken lake/ prairrie creek site, just after you go across the crick. river access, a crick and a lake. picnic areas as well. perfect place for family outing. couple ice cream joints in wilmington as well. just get off at wilmington exit off i-55.
if you go the other direction park at the trap range and walk across the road for river access. more access in the rest of the DPCA further down that road. decent boat launch if you have water craft. also access to backwater areas down the road.