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American eel © 2009 TNC/Sally Harold

“Now, when eels are migrating, we’ll be able to see how they’re doing and make sure they’re not hurt during their passage through the siphon.”

Sally Harold, Saugatuck River Watershed project director

On a cool night in September, female eels leave Connecticut’s dark waterways for their spawning grounds in the Sargasso Sea near Bermuda. As they approach a water treatment plant’s intake grates, they are met with glowing underwater lights. Veering away, they slip through a siphon that carries them safely into the Aspetuck River.

The last time the American eels made this journey, hundreds perished in these same grates. What’s new this year is a set of underwater lamps that provides a warning to move away.

Getting the “Green Light”

Knowing that eels avoid light, the Conservancy partnered with Aquarion Water Company  to install solar- and wind-powered lamps that route the eels to safety. “We knew eels were perishing and we wanted to correct that,” says John Herlihy, Aquarion’s director of water quality and environmental management.

“Aquarion is a water supplier, but we also see ourselves as stewards of the environment.” The lights discourage eels from entering the treatment plant, and they head instead toward a dark area where a new, eel-friendly siphon carries them over the reservoir’s spillway.

“Now, when eels are migrating, we’ll be able to see how they’re doing and make sure they’re not hurt during their passage through the siphon,” says Sally Harold, the Conservancy’s Saugatuck River Watershed project director. “We hope this year to find most eels downstream, and far fewer in the intake traps.”

A Local Staple, a Global Journey

American eels are a key link in Connecticut’s freshwater food chain, snacking on mayflies, tiny fish and other small aquatic species while serving as dinner for larger bass and trout. But what makes the eels stand out is the remarkable journey they make to the Sargasso Sea near Bermuda, where they mingle with eels from as far as Greenland and South America to spawn. Larval eels then drift into the warm Gulf Stream, which carries them to the North Atlantic coast.

This trek is difficult in itself, but made more so in densely developed Fairfield County, where eels must negotiate numerous small dams to reach upstream habitat and avoid the water treatment plant intakes on their way to sea. By ensuring that more eels and other migratory fish reach their breeding grounds safely, the Conservancy is helping regain healthy population levels of these fish and maintain their important role in our rivers.

Success here could also pave the way for similar projects in other rivers that are home to American eels, and Harold is encouraged by the active partnership with Aquarion Water Company. “This is the first time a private water company has worked with us to assist eels with safe passage downstream,” Harold says. “We’re hoping it will set a precedent.”

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