The first dams at Sunbury, Pennsylvania were to support year round ferry crossings.
Conowingo Dam[1] is credited with preventing much of the silt from Pennsylvania from reaching the Chesapeake Bay.
The dams from York Haven down to the Chesapeake all have fish ladders or lifts in an attempt to mitigate this.
Communities on the river edge have been displaced, such as Conowingo, Bald Friar, and Glen Cove, Maryland in 1928.
The river also grows its own ice dams during the winter and notable ones will be included.