The Fish and Boat Commission and Wildlands Conservancy recently completed the Lehigh River Fish Passage Improvement Feasibility Study through a contract to KCI Technologies, Inc., an engineering consulting firm.

The study was funded by a grant from the American Rivers & National Oceanic and Atmospheric Administration Community-based Restoration Program and funds from the Palmerton Superfund settlement account. More than 70 stakeholder groups and agencies were invited to participate in the study process.

The objective of the project was to investigate options for improving fish passage at the Easton and Chain Dams along the Lehigh River, while providing a mechanism to sustain water flow into the Lehigh and Delaware Canals, which are currently watered by the two dams.

Although there are currently fishways on the Easton Dam, the Chain Dam and the next dam upstream, the Hamilton Street Dam in Allentown, they have proven to be very inefficient for passing migrating shad.  After much study, it has been concluded that the only feasible way to allow fish migration into the river in substantial enough numbers to allow populations to recover is to remove the dams.

A process will now begin to evaluate the risks, costs, and benefits associated with either dam removal, or the “no action” alternative, which would result in the current fishways continuing to operate in an inefficient manner.

The Lehigh River has been used and enjoyed by countless generations, from the first Native Americans to settle upon its banks; to the many industrialists who used it to produce iron, cement and steel; to the recreational boaters, anglers, and wildlife enthusiasts who love the river today.

In the 1970s the passage of the Clean Water Act began the environmental movement that has since led to dramatic improvements in the ecological health of the River. But the Lehigh still faces enormous challenges, which include the existence of large dams that adversely affect water quality and aquatic and riparian habitat, prevent the natural movement of many resident and migratory fish species, exacerbate flooding and erosion, and are significant public safety hazards.

The dams constructed on the Lehigh River during the 1800s have resulted in the near extirpation of American shad and other migratory fishes, including hickory shad, blueback herring, and alewife, from the Lehigh. The American shad is an anadromous fish that lives much of its life in the Atlantic Ocean, but must migrate into freshwater rivers and streams to spawn.

Before the dams were constructed, shad were an extremely abundant and very critical component of the Lehigh River ecosystem. Creation of the dams stopped shad migration into the Lehigh River. Removing dams will allow shad and other migratory fish to return to the Lehigh and will allow resident fish to move freely throughout the river.

Restoration of American shad was the primary impetus for undertaking this project, but the many potential social and environmental benefits that could result would extend far beyond fish.

For over 30 years, the Fish and Boat Commission, Wildlands Conservancy, and their partners have been attempting to restore American shad to the Lehigh River through a combination of stocking and provision of fish passage at existing dams. The Easton and Chain Dams, which are the focus of this study, have existing fishways (installed in 1994), but monitoring indicates that passage is very inefficient and inadequate to support the restoration of a self-sustaining population of American shad.

The study evaluated a wide range of engineering options to improve fishway efficiency but dam removal was found to be the only viable option to restore the fishery.

A copy of the study is available online.

Please send your comments on the study by email to: feasibilitystudy@wildlandspa.org by 5 p.m. on June 2.

5/27/2013