Cumberland Dam
The 928th tallest dam in the world
The Cumberland Dam was a dam that was built across North Branch of the Potomac River in Cumberland, Maryland, for the purpose of diverting water from the river into the head of the Chesapeake and Ohio Canal. The Chesapeake and Ohio Canal Company began construction of Dam No. 8 in 1837 and work proceeded intermittently, finally concluding in 1850. The dam impounded water over a distance of a mile, causing back water for about 3 miles (4.8 km) up the river. Above the dam is the mouth of Wills Creek.
Dam data from Wikidata (CC0) plus curated additions. Summary from Wikipedia (CC BY-SA).