Did man-made modifications to Conewago Canal and Tennessee–Tombigbee Waterway assist in navigating these passages?
Conewago Canal:  Two lift locks overcame 19 ft of elevation between the ends of the canal, and a guard lock blocked unwanted water, particularly during floods. Conewago Canal:  Cargo could go upstream as well as down. Tennessee–Tombigbee Waterway:  The Tennessee–Tombigbee Waterway links commercial navigation from the nation’s midsection to the Gulf of Mexico. Tennessee–Tombigbee Waterway:  The major features of the waterway are 10 locks and dams, a 175 ft deep cut between the Tombigbee River watershed and the Tennessee River watershed, and 234 mi of navigation channels.
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