WESTBROOK – Sappi Fine Paper North America has begun work on a multi-million-dollar project to build a new fish ladder system at the Cumberland Mills Dam to help restore populations of migratory fish.

Barry Stemm, an engineering manager at Sappi who is in charge of the project, said the company, which owns the dam, agreed to do the project last fall. The decision came after negotiations with a number of environmental groups, including the state Department of Inland Fisheries and Wildlife, which lasted more than three years.

The project, Stemm said, will be done in two phases. Phase 1 involves repairing a series of gates that regulate water flow through the dam.

“We need to control the water to make the fish ladder work better,” he said.

Stemm said Sappi workers expect to finish Phase 1 this fall. In the spring, the company will begin Phase 2, which is the construction of the ladder itself.

The ladder, Stemm said, is a Denil ladder design, which contains a series of baffles built into a 300-foot ramp. This creates varying speeds of water, which is intended to accommodate different species of fish.

“It basically slows the water flow down the ramp enough so the fish can swim up it,” Stemm said.

The dam, Stemm said, was built 150 years ago to help drive plant machinery. Today, he said, the dam helps supply the plant with fresh water.

The project came out of negotiations that began when environmental groups lobbied Sappi to do something to help restore migratory fish populations. In particular, according to the wildlife department, the ladder is expected to help alewife, blueback herring, American shad and American eel. The fish need to travel up the Presumpscot River to spawn, but are blocked by the Sappi dam.

The department approved a proposal last October drafted by Sappi and the environmental groups, which include Friends of the Presumpscot River, American Rivers, the Department of Environmental Protection, the Department of Marine Resources, and the U.S. Fish and Wildlife Services.

A spokesperson for the Friends of the Presumpscot River said the passageway would have long-term benefits by bringing fish populations upstream and attracting wildlife such as eagles and osprey.

Sappi Fine Paper North America is upgrading these flow control
gates as the first stage in creating a fish ladder at the
Cumberland Mills Dam. The ladder will allow migratory fish to
bypass the dam, swim upstream and spawn. (Staff photos by Sean
Murphy)

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