AUGUSTA, Maine -- Maine conservationists say four dams on the Kennebec River are the biggest threat to Atlantic salmon populations, and groups intend to sue to get them removed.

Brookfield Renewable Partners is an international energy company that owns four dams on the Kennebec River between Waterville and Skowhegan.

Nick Bennett, staff scientist for the Natural Resources Council of Maine, noted one of the best spawning habitats for Atlantic salmon is in the Sandy River, a tributary above Brookfield's dams. Atlantic salmon are known as "sea-run" fish, they spawn in fresh water but spend much of their lives in salt water.

He said the dams pose an often fatal hazard for the fishes' path to the ocean.

"They really need to be removed if we want to have any chance of restoring Atlantic salmon and the other species of sea-run fish that are necessary for them to be restored like river herring, shad and eels," Bennett asserted.

Groups claim the dams violate the Endangered Species Act (ESA).

The Conservation Law Foundation, Maine Rivers and the Natural Resources Council of Maine have given the required 60-day notice to sue companies under the ESA.

Bennett emphasized when it comes to restoring the species, groups are laser focused on the dams. He pointed out historically, the Kennebec River has been the largest Atlantic salmon run of any river in the U.S.

"These four dams block Atlantic salmon, both from getting up to the Sandy River to spawn, and from getting out of the Sandy River to head back to the ocean to grow into adults," Bennett explained.

Last July, the federal government rejected a Species Protection Plan proposed by Brookfield, and the Maine Department of Marine Resources and the National Marine Fisheries Service have recommended the removal of one of the dams.

The company shut down three of its four dams for salmon migration earlier this month, with operations set to resume May 31.

SEATTLE -- How water flows in cities affects salmon swimming far away. An event this week is exploring how urban centers can better treat their water to protect these iconic Northwest species.

Salmon in the City is an online presentation that will look at approaches to architecture that keeps water clean for aquatic species.

Anna Huttel, certification director for Salmon-Safe, the organization promoting best conservation practices hosting the event, said one of the options cities can use to treat stormwater is planters.

"Bio-retention offers that above-ground visibility to inspire folks," Huttel pointed out. "As well as the opportunity to use plants to help to treat pollutants in the stormwater, provide habitat through the vegetation and really just provide something that's beautiful to look at as well. "

The event begins at 5:30 p.m. Thursday with presenters including Huttel and Brook Muller, Dean of the College of Arts and Architecture at the University of North Carolina-Charlotte. She will speak about sustainable architectures and climate-adaptive urban landscapes.

Huttel stressed her organization focuses on salmon because they are like canaries in the coal mine for habitat health, but Salmon-Safe could just as easily be called "water safe" because practices that are good for salmon are good for other species as well.

"Thinking about how these principles can help downstream, even if you can't see a water body from a site that you are influencing, everything has a trickle-down effect, reaches a larger water body and touches another part of the ecosystem," Huttel outlined.

Huttel also noted salmon are imperiled, affecting another iconic species of the Northwest: orcas. The whales, which live off the West Coast, rely on salmon for their diet and have increasingly struggled to find the food they need to survive.

BOISE, Idaho -- Closed fisheries from imperiled fish runs in the Columbia River Basin are prompting calls for action before it's too late.

Steelhead trout numbers in the Columbia and its tributaries could be the lowest since records began in the 1930s. On the Columbia, the Oregon Department of Fish and Wildlife issued an emergency closure on salmon fishing up to the Bonneville Dam.

Brian Brooks, executive director of the Idaho Wildlife Federation, said low salmon and steelhead numbers present an existential crisis for people in the industry.

"Idaho guides and outfitters, if they want to stay in the fishing industry, they have to leave their home," Brooks observed. "They have to go out of Idaho to stay in the industry, and if they don't want to leave their home, then they have to leave the industry."

Brooks applauded Republican Idaho Congressman Mike Simpson for his $33 billion proposal to save endangered species, which includes removing the lower Snake River dams. Other leaders in the region have supported habitat improvements in Congress's infrastructure package, but have not moved to include Simpson's proposal in the package.

Marcia Brownlee, program manager of the Artemis Sportswomen initiative for the National Wildlife Federation, said the region has taken half-measures to save endangered fish for too long.

"We need to do everything in our power to make sure emergency closures do not become permanent closures," Brownlee urged. "And what we've seen this summer has really illustrated that what we're doing now isn't enough. We need to do more."

Brownlee recommended the first step should be removing four lower Snake River dams in southeast Washington.

Earlier in the year, Rep. Cathy McMorris Rodgers, R-Wash., and Dan Newhouse, R-Wash., praised spring Chinook salmon runs on the Snake River, which were higher than in 2019 and 2020. The members of Congress said it was proof dams and salmon can co-exist.

BANGOR, Maine -- Efforts are under way to restore Atlantic salmon populations in the Gulf of Maine, by removing dams, replacing culverts and restoring streams.

Salmon are what are known as sea-run fish, meaning they live part of their lives in fresh water and part in the ocean.

John Catena, Northeast and Great Lakes region supervisor for the National Oceanic and Atmospheric Administration (NOAA) Restoration Center, said dams across the region have blocked Atlantic salmon's migration paths from the ocean to the river to spawn.

This year, four local Maine projects are receiving $900,000 in funding from NOAA.

"These kinds of activities are meant to recover them such that we can actually have a sustainable population over time," Catena explained. "This is an iconic species that was important to Native Americans to sport fishermen, and to any number of other groups throughout the region."

Catena noted Atlantic salmon are endangered, with roughly 1,000 in the Gulf of Maine, where there used to be more than 100,000. He added these kinds of projects also benefit species similar to Atlantic salmon, including river herring and American shad, which also have low populations.

Catena pointed out dam-removal projects have implications beyond removing blockages to fish migration, and many present liability issues for local communities.

"They continue to cause other problems," Catena outlined. "They can degrade water quality, increase the water temperatures, exacerbate local flooding. And so these are oftentimes left to dam owners that don't have the means to deal with them."

Catena emphasized federal infrastructure funding also may help improve thousands of dams and culverts throughout Maine. Many are old and degrading former mill structures. A $1 trillion infrastructure bill is in the works in Congress, passed by the Senate and now being debated in the House of Representatives.