In 2004 an energy company (PPL corporation) and a coalition comprised of the Penobscot Nation, resource agencies and non-governmental conservation organizations announced a collaborative agreement to restore migratory fish populations in the Penobscot River basin (Maine, USA). In addition to producing diverse regional benefits, the Penobscot River Restoration Project (the ‘Project’) provides a clear demonstration of the benefits of basin-scale approaches for managing existing hydropower dams as well as illustrating key concepts for sustainable hydropower for regions of the world currently undergoing hydropower development.
The Penobscot basin is the largest in Maine and historically has supported culturally and economically significant populations of migratory fish, including Atlantic salmon, shad and blueback herring. These migratory fish populations declined dramatically following the construction of a series of hydropower dams on the main-stem river and major tributaries in the early 20th century.
The Project resulted from PPL’s simultaneous application for new licenses from the Federal Energy Regulatory Commission (FERC) for 10 of its dams in the basin and one dam in an adjacent basin. Through the relicensing process, PPL and the coalition of stakeholders reached a multi-party settlement agreement that included the sale of three dams to a newly created non-profit organization, the Penobscot River Restoration Trust. The Trust will remove the two most seaward dams and construct a bypass around the third dam. The agreement also included provisions for PPL to make operational changes and fish passage improvements at the other dams. The Trust will remove the two most seaward dams and construct a bypass around the third dam.
When the Project is complete, accessible habitat for the basin’s migratory fish will increase by nearly 2,000 km with no decrease in total energy production (energy production may increase slightly). Fisheries biologists estimate that populations of migratory fish in the basin will increase dramatically: Atlantic shad populations are projected to increase from near zero today to more than 1.5 million, and Atlantic salmon are predicted to increase from below 1,000 currently to more than 10,000, re-establishing the Penobscot as the most important river for Atlantic Salmon in the United States.
In addition to these biological gains, the Project is projected to have significant economic and cultural benefits for the Penobscot Nation and riverside communities. Because the Project encompasses an entire basin, its benefits will go far beyond the incremental environmental improvements that typically accompany single-project FERC relicensing processes. The basin-scale approach will allow the Trust to completely remove those dams that had the biggest environmental impact and, simultaneously, PPL will be able to generate more energy from those dams that have lower environmental impact.
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