Fish Passage

Rocks to be removed from stream for fish passage
Dam in stream
Dump truck for removing large rocks from Nine Mile Run stream in Pittsburgh PA
Dump truck hauling away large rocks for stream restoration in Pittsburgh PA

Fish Passage

Many fish must travel upstream to complete their lifecycle, a journey that is impossible if there are structures impeding the way.

Over a lifetime, all rivers and streams evolve – courses shift, pools become deeper or shallower, rocks shift. After numerous high-flow events, there were a number of areas in the stream at Nine Mile Run where riffles needed to be adjusted to decrease the vertical distance between the downstream and upstream water level. In 2018, we partnered with the City of Pittsburgh and Dave Derrick to complete a partial stream restoration aimed at ensuring that fish would be able to safely and successfully travel upstream.

As we monitor the stream, we can see the impact: greater fish diversity, greater quantity of fish recorded during sampling and a more ecologically sound space, one that provides food for a number of animals, including the belted kingfisher and northern water snake, among others.


City of Pittsburgh
Dave Derrick