Hargus Lake Dam Improvements

Aerial view of Hargus Lake Dam

Hargus Lake Dam Improvements

Deploying Innovative Solutions to Protect Communities

Constructed in 1949 and in its current configuration since 1955, the Hargus Lake Dam is one of Ohio’s 450 high-hazard dams, with the potential to impact lives and property if it failed. The 1,550-foot-long, 67-foot-tall earthen embankment impounds a 130-acre lake and holds 1,800-acre feet of water. It also includes a reinforced concrete pipe primary spillway and 185-foot-wide earthen auxiliary spillway. In 2020, the Ohio Department of Natural Resources selected HDR to design the Hargus Lake Dam Improvements project, part of the client's Dam Safety Initiative aimed at reducing the risk of state-owned dams and expediting the rehabilitation of 57 dams deemed high hazard. 

Using an innovative construction manager at risk delivery approach, the Hargus Lake Dam Improvements project provided a new spillway, installed a seepage collection system and stabilized the embankment by flattening the downstream slope using soil from on-site locations, which saved more than $1 million in costs. 

With the dam’s nearby location to A.W. Marion State Park, the team also focused on public benefits to the area throughout the project cycle. We restored the site with native plantings, maintained recreation access throughout construction, leveraged structural components to enhance the park experience and created new trails below the dam and to the pier — which doubled as maintenance and inspection access points. 

The project team worked collaboratively to accelerate concrete placement in order to complete the spillway before winter shutdown, allowing lake levels to rise back to normal pool and provide a full recreation season in 2022. The $10-million project was completed ahead of schedule in August of 2022 and under budget. 

Aerial view of Hargus Lake Dam
Ohio Department of Natural Resources

Circleville, OH
United States

1,550-foot-long, 67-foot-tall earthen embankment storing 1,800-acre-feet of water


Honor Award (2023)
Engineering Excellence Awards
American Council of Engineering Companies of Ohio