By NATHAN LYNCH

Special to the Journal Tribune

KENNEBUNK — Residents recently packed the auditorium of Town Hall to hear a presentation by groups interested in eliminating dams on the Mousam River.

The panel discussion was hosted by the Maine Rivers organization, which advocates for healthy river ecosystems, and the Sierra Club of Maine. Panelists included representatives of the Marine Fishery service, the Atlantic Salmon Federation and the Wells National Estuarine Reserve.

The three dams on the lower half of the Mousam River ”“ Twine Mill, Dane Perkins and the Kesslen dam are operated by the Kennebunk Light and Power District. First licensed in 1982, the hydroelectric dams are up for relicensing by the EPA in 2022, a lengthy process that would likely cost close to a million dollars to complete. The trustees of the KLPD noted they would decide whether to seek relicensing of the dams by the end of 2015.

Presenters addressed some of the environmental and ecological results of a 90-year-long impound of the Mousam River, which has kept many species from traveling along the length of the nearly 30-mile river. Initial estimates are that removing the dams would introduce nine additional miles for fish passage along the river.

John Burrows of the Mousam and Kennebunk Rivers Alliance, who works to remove dams across Maine and Canada, illustrated several of these problems.

“The Mousam is one of the most heavily dammed rivers in the state of Maine. There are 12 or 13 dams, one less than every two miles … and (it is the) only major river that has no fish passage,” Burrows said.

Burrows estimated that over a million new fish could be introduced if the dams were removed, including Shad, Alewife and Atlantic Salmon. These species include fish that use the river to spawn, as well as fish that live in the river after spawning in the ocean.

Residents asked a number of technical questions about what would happen to the river flow if the dams were to be removed, including the resulting depth of the river, as well as the conservation status of the species that would be reintroduced to the river ecosystem.

Another alternative proposed was “fish ladders” ”“ bypasses around the dam that allow fish to move. Burrows called them a “half-measure” that would do little to resolve the fundamental habitat disconnect that causes problems, and said they likely would work for only a few species of fish.

The most common question from residents was about property value ”“ whether removing the dams and making the river free-flowing would damage property value and whether there would be reimbursement.

Panelists said they weren’t sure if there was a precedent for reimbursement, nor were they sure what effect the river restoration would have on property values, but they agreed that people value rivers for different reasons and that a free-flowing river may attract different types of home buyers.

“There is going to be a loss of use for one type, but there’s going to be a gain of use for another,” Jacob Aman of the Wells Estuarine Reserve said.