The Thomas Hill Reservoir Conservation Area property is owned by Associated Electric Cooperative Inc. of Springfield, MO. The reservoir was constructed to provide a source of water to cool the power plant during energy production. The public is restricted from a small portion of the area near the power plant.

The area is managed by the Conservation Department under a multi-year lease. The area consists of the 4,950-acre Thomas Hill Reservoir, surrounded by 4,381 acres of land which is approximately 60 percent open and 40 percent forested. The area has 2.2 miles of stream frontage on the Middle Fork of the Little Chariton River. The north end of the reservoir features several wetland units, created and maintained by beavers, that attract a variety of nesting and migrating birds.

Management of the area includes farming, timber harvest, and controlled burns to improve wildlife habitat and increase species diversity.

Thomas Hill Reservoir is managed primarily for largemouth bass, crappie, hybrid striped bass and catfish. The warm water discharge remains ice-free during the winter providing a unique winter fishing opportunity.

Bald eagles are present on the reservoir and can usually be seen from Route T, especially in the winter.

The area also has an improved campground with concrete pads, shelters, fire grates, and privies. Three concrete boat ramps are located on the lake.