Centennial Island Fish Passage: A New Path Forward

Centennial Island has long been an important part of the Concord River, supporting hydropower, recreation, and wildlife. For decades, the existing Denil fish ladder has helped migratory fish bypass the Centennial Island Dam, but it no longer provides effective passage for many native species. Restoring fish migration is essential to reconnecting the Concord River with the Merrimack River and the Atlantic Ocean.

Today, plans are underway to replace the aging fish ladder with a nature-like fishway that mimics a natural stream. The new design will improve fish passage for a wider range of species while enhancing river health, habitat, and long-term resilience.

This interactive StoryMap explores the history of Centennial Island, the importance of migratory fish in the Concord River, the existing fish ladder, and the vision for a new nature-like fishway that will reconnect the river for generations to come.

Centennial Island Fish Passage StoryMap

Learn More About River Restoration Across Massachusetts

• Massachusetts Division of Ecological Restoration

• Merrimack River Watershed Council

Get Involved

• Attend upcoming community meetings on dam removal projects

• Volunteer with local river cleanups and restoration projects

• Share this StoryMap with neighbors, educators, and friends