Strong Pond Dam Demolished, Reopens 10 Miles of Fish Passage to Norwalk River, Restoration Efforts Continue

In September 2023, CT DEEP and partners removed Dana Dam, also known as Strong Dam, from the Norwalk River located in Wilton, CT, opening 10 miles of river for fish passage. The dam’s removal has been a multi-year project which reconnected fourteen miles of free-flowing river to Long Island Sound.

A look at Dana Dam following the dam’s removal last year. The removal of Dana Dam converted what was once stagnant water back into a free-flowing river that moves sediments downstream, contributing to streambed habitat and sustaining critical coastal marshes. Photo courtesy of Save the Sound
This article was originally published in December 2022 as part of the Bipartisan Infrastructure Law fact series. It was updated on August 22, 2023 and again on February 15, 2024. You can view the original fact sheet here.

With funding from the Bipartisan Infrastructure Law (BIL), the Connecticut Department of Energy and Environmental Protection (CT DEEP) completed the removal of Strong Pond Dam in Wilton, CT, on September 11, 2023, opening an additional 10 miles of river habitat for migratory fish swimming from Long Island Sound.

The Strong Pond Dam, also known as the Dana Dam, was the first barrier migratory fish encounter after swimming upriver on the Norwalk River from Long Island Sound. Planning for its removal began in the 2000s.

In 2020, LISS awarded CT DEEP $2.2 million for the dam’s removal and demolition began in 2021. The final phase of construction, completed in September 2023, focused on removing the dam and restoring the river section. To support the final demolition phase, LISS contributed an additional $250,000 to the project using BIL funds.

Over the next year (2023-2024), efforts will focus on restoring the riverbank, which will include planting 1.5 acres of vegetation to benefit birds, mammals, amphibians, and other wildlife. Save the Sound, a LISS partner, will document regrowth and monitor the passage of migratory and resident fish populations up the Norwalk River. The former site of Dana Dam is expected to return to its natural state over time. 

Funding was administered through CT DEEP, and the project was led by LISS partner Save the Sound, with collaboration from Trout Unlimited, the Norwalk River Watershed Initiative, and the Town of Wilton.

A rendering of what the Norwalk River will look like in Wilton, CT after the Strong Pond Dam is removed and the riverbanks are restored. Save the Sound image
A rendering of what the Norwalk River will look like in Wilton, CT after the Strong Pond Dam is removed and the riverbanks are restored. Save the Sound image

Improving access for migratory fish in the Norwalk River is an important step to restoring the health of the river and Long Island Sound. Important species like herring and sea lamprey previously had no access to these historic spawning grounds since construction of the dam.

With its removal, these species can reach the spawning grounds and improve the ecological balance in the river and Sound. Flooding around the dam had also threatened parts of Downtown Wilton and the nearby railroad infrastructure. These risks have been reduced with the dam’s removal.

Since 1998, the Long Island Sound Study and its partners have successfully reopened nearly 433 miles of rivers and streams for fish passage in Connecticut and New York.

Please complete your newsletter signup.


Subscribe to receive our e-newsletter, Sound Bytes by providing your email address. Interested in a free copy of our print newsletter, Sound Update? Then also provide your home/company/school address.