LOCATING A SUBMERGED HISTORIC DAM IN THE CUYAHOGA RIVER, OHIO USING GROUND PENETRATING RADAR

In 1951, the Brecksville Dam was constructed on the Cuyahoga River in northern Summit County, Ohio. This new concrete dam replaced the Pinery Feeder Dam, an aging wooden-crib dam built in 1827. The Pinery Feeder Dam was left in-situ upstream of the new dam and was submerged within the new dam pool. Dam removal efforts along the Cuyahoga River have prompted diverse studies of each dam considered for removal, including studies of historic structures. Here we report on a geophysical investigation within the Brecksville Dam pool undertaken to ascertain and delineate the location of the historic Pinery Feeder Dam. A Geophysical Survey Systems Inc. (GSSI) ground penetrating radar (GPR) system with a 120 MHz antenna was deployed in a rubber boat. A gridwork survey of 28 tracklines was performed to provide complete coverage within the dam pool. The Pinery Feeder Dam was identified as a shallow bathymetric feature atop the flat bedrock river bottom. The dam was groundtruthed by a person physically entering the water. The GPS positions of the dam feature were plotted in ArcMap and revealed a V-shaped pattern pointing upstream. In addition, the approximate extent of the Pinery Feeder Dam was delineated and mapped out. This study demonstrates that GPR can be successfully used in river settings to map out historic structures and aid in dam removal studies.