American Eel Restoration To The Susquehanna River

The Susquehanna River is the largest tributary to the Chesapeake Bay and encompasses over 40% of the Bay’s drainage area.  The Susquehanna has four hydroelectric dams on the main stem, all occurring between river miles 10 to 65.  Conowingo Dam was constructed in 1928, and is the lowermost dam on the river and precluded all eel migrations into the Susquehanna River watershed.  Since 2005, the U.S. Fish and Wildlife Service has been perfecting elver collection techniques at the base of Conowingo Dam.  Total number of annual elver captures has steadily increased from 81 in 2005 to 127,000 in 2012.  The U.S. Fish and Wildlife Service has relocated nearly 212,000 elvers collected at Conowingo dam into Susquehanna River watershed since 2008.  In addition, over 100,000 glass eels collected from the Atlantic Coast of Maryland have also been relocated into the Susquehanna River watershed.  Fisheries surveys have determined that the eels have dispersed at least 19km upstream and 82km downstream from stocking locations within two years.  The U.S. Fish and Wildlife Service has also conducted a preliminary downstream migration study at Conowingo Dam to evaluate the potential impacts of turbine related mortality of silver eels.  Results from upstream and downstream passage studies will be valuable tools to promote American eel restoration to the Susquehanna River during the FERC relicensing negotiations that are occurring for three of the five main stem hydroelectric projects.