Progress toward this outcome is measured against a 2011 baseline of 2,510 stream miles open to the migration of fish. Between 2012 and 2017, 1,236 additional miles were opened to fish passage, surpassing the 1,000-mile goal.
Stream Miles Opened to Fish Passage (Cumulative) (2012-2017)
Streams Opened to Fish Passage (1989-2017)
Of the miles opened to fish passage between 2012 and 2017, 52 percent (or 648 miles) are located in Pennsylvania and 46 percent (or 565 miles) are located in Virginia. The remaining 22.6 miles are located in Maryland.
Since this outcome’s mileage target was set in 2014—to mimic the fish passage goal stated in Chesapeake Bay Executive Order 13508 of 2010—experts have developed a more accurate method of calculating the stream miles opened to fish passage following the removal of a dam or other barrier. This method uses the Chesapeake Fish Passage Prioritization Tool to map and count the available upstream miles located between a removed blockage and the waterway’s headwaters or the next blockage that is in place. The prioritization tool is also used to assess potential projects.
Because this outcome’s mileage target was set under a previous method of calculation, it is an unfit benchmark against which to measure progress. While much of the “low-hanging fruit” with regards to dam removal has been picked, our partners will continue to open stream miles to access by migratory fish. Opportunities to restore fish passage through the retrofitting or removal of culverts—in addition to the removal of dams—are also being investigated.
Dams, culverts and other barriers inhibit stream flow, limit stream habitat and block migratory fish from reaching their spawning grounds. Removing these barriers can restore water flow, reduce sediment build-up and allow shad, herring and other migratory species to move between fresh- and saltwater habitats.