After almost a quarter century as an environmental education center alongside one of the state’s largest hydropower plants, the Amoskeag Fishways in Manchester will close next month and be reduced to a springtime observation deck for the dam’s fish ladder.

The move comes after Eversource sold off the hydropower facility last year along with all its other power plants in New Hampshire as the final step in electricity deregulation. Amoskeag Hydroelectric Station on the Merrimack River, alongside Exit 6 of I-93 in Manchester, is one of nine hydropower dams that were sold to Maryland-based Hull Street Energy for $83 million.

“The new owners weren’t quite sure what they were going to do with us. They have decided to have the center only be a seasonal interpretative center, instead of open year-round,” said Helen Dalbeck, director of the Fishways.

The center is slated to close a week later on March 8, with the seasonal fish ladder reopening March 11.

The Fishways is holding a celebration of its history Friday from 3 to 5 p.m.

“It will be classic Fishways – we’ll make fish hats, play Fish Twister, and celebrate everything we’ve done,” said Dalbeck. “Everybody’s invited.”

The new arrangement at the site harkens back to the early days of the fish ladder. The facility was built in 1989 to help Atlantic salmon, herring, shad and eels move up and down the Merrimack River without being blocked by the dam or killed by the spinning turbines that generate electricity. These species, known as anadromous fish, live both in the ocean and in fresh water, and must move between them in order to spawn.

The fish ladder has a large window that lets people see the species passing through. In 1991, Eversrouce, then known as PSNH, began running some programs at the ladder. In 1995 the company joined with New Hampshire Audubon, the New Hampshire Fish and Game Department, and the U.S. Fish and Wildlife Service to create the Amoskeag Fishways.

The site has hosted a variety of educational programs since then on topics ranging from river wildlife to electricity to Native American history.

The Amoskeag Fishways has three full-time employees.

The dams are owned by a Hull Street affiliate called Central Rivers Power.

(David Brooks can be reached at 369-3313, dbrooks@cmonitor.com or on Twitter @GraniteGeek.)]]>