East Fork State Park is a state park located in Clermont County, Ohio, United States, about 25 miles east of Cincinnati. It has camping, hiking, swimming and boating opportunities. The state park is home to many junior and collegiate rowing races, including the US Rowing Youth National Championships. The main lake in the park is William H. Harsha Lake. The large earthen dam, and smaller saddle dams, are operated by a crew of U.S.