Over 3 miles of Tarryall Creek flows through the Allen Creek Ranch. Habitat improvement and fencing work was accomplished on the property in both 2005 and 2011 to decrease erosion, increase riparian habitat, and further enhance the property for deer, elk, waterfowl, songbirds, beaver and trout. Allen Creek Ranch is now two different ranches (Allen Creek Ranch and Historic Williams Ranch), both of which are available for limited public fishing, by reservation only, at South Park Fly Fishing.
Funding for habitat improvements on Allen Creek Ranch and the Historic Williams Ranch was provided in part by the Park County Land & Water Trust Fund.