Evaluation of Navigation Dam Effects on Riverbanks

A study was conducted between 1978 and 1984 in a 72 mile-long stretch of the Ohio River to detect the influence of construction of the Smithland Locks and Dam on bank instability. Changes in bank appearance were noted during four inspections made before dam construction and pool raise, and during two inspections made after pool raise. The navigation dam raised river pool levels as much as 22 feet. During inspections, the entire extent of the stream affected by the navigation dam was evaluated. Banks were classified (high-eroded, low-eroded, vegetated, etc.). Correlations of erosion classification with magnitude of pool raise, planform location, and other factors were attempted. This work extended previous site-specific erosion evaluations and studies in other reaches of river. This was the first before dam-after dam study of bank erosion, of this kind, ever published. It was found that raising the navigation pool in 1981, had no effect on riverbank appearance and apparent erosion between 1978 and 1984.