By Brian Hamilton
How would you react if you were driving home one day and there was a roadblock stopping you from making your destination? You’d feel confused and would probably try to find an alternate route. What if every other route you knew was blocked as well? For many fish species this is a real problem they encounter when facing dams on rivers and streams.
Most migratory fish species swim from saltwater to freshwater to spawn, and dams can impede their natural path. One way to help fish bypass a dam and complete their journey is to construct a fish ladder.
Fish ladders are structures that are on or around artificial barriers, such as dams. The ladders allow the fish to gradually swim into successive upstream chambers and avoid the impediment. The styles can vary, but the end goal is to get the fish up and over the dam.
The Mid-Atlantic region is home to several fish ladders, including one in Philadelphia constructed in 1979 and renovated in 2009 to help boost fish over the Fairmount Dam on the Schuylkill River.
The Philadelphia Water Department operates a monitoring program to check on the resurgence of key migratory species, and even has a “Live Fish Cam” you can bookmark by clicking here.
The 2010 fish passage season at the Fairmount Fishway was a record-breaking year, with 2,521 American shad ascending the fishway. This was the highest ever recorded and more than seven times greater than passage numbers prior to the renovations. Hickory shad, listed as a state endangered species in Pennsylvania, also showed an increase in passage and exceeded all previous records. In addition to migratory species, fish passage for key resident species, such as walleye, topped previous marks and was more than three times greater than pre-restoration.
Learn more about the Fairmount Dam Fishway by clicking here.
About the Author: Brian Hamilton works in the Water Protection Division’s Office of Program Support at Region 3. He helps manage the Healthy Waters Blog, and assists in reviewing mining permits and does other duties as assigned. Brian grew up in Central Pennsylvania. He has worked for the EPA since July 2010.