The park is a haven for many different species of wildlife. At the lake's far north end, the Iowa Department of Natural Resources maintains a game management area open to public hunting. Thousands of ducks migrating to their summer breeding grounds take refuge in the solitude of Rock Creek. The concentrations of teal, bluebills and mallards offer an excellent opportunity for bird watching. In the spring, ducks in their full plumage perform their courtship flights. Even in winter, mallards may often be seen on the south end of the lake where the spillway area is relatively free of ice. A variety of animals including white-tailed deer are often seen by park visitors.

Rock Creek is one of central Iowa's camping hotspots. The large campground bordering the lake has 200 campsites (101 with electrical hookups) and modern rest rooms and showers. Starting February 13, 2006 advance campsite reservations can be booked through the park reservation system. Half of the campsites are still available for self-registration on a first-come, first-serve basis.

Fishing:

The lake's 15 miles of shoreline gives anglers a chance to try their hand at catching bass, crappie, bluegill, catfish, saugeye and bullhead. The deepest water is approximately 18 feet and the average depth is about nine feet. The lake is excellent for trolling or casting. Ice fishing offers anglers a chance to catch king-sized bluegill and crappie.