The largest river restoration project on the East Coast is in progress on the St. Croix River as a collaboration of cross border entities, represented by the International St. Croix River Watershed Board (ISCRWB), continues its work to return alewives, also known as river herring, to the waterway. The results are promising, with fish counts continuing to increase and significant developments, including the decommissioning of the Milltown dam, having happened since the counts took place. The findings, along with reports on the developments of fishways, were presented during a public meeting of the ISCRWB on March 6.
      Alewife runs on the St. Croix River have faced challenges for decades since the Maine government ordered the closure to fish passage of the Vanceboro dam in 1987, the Grand Falls dam in 1991 and the Woodland dam in 1995 following protests from sports fishermen who saw alewives as interfering with smallmouth bass populations. As a result, the alewife count at Milltown dam was only 900 in 2001, a significant decline from the 2,625,000 counted in 1987.
      With the ISCRWB's contention that alewives are an ancestral species to the St. Croix, Maine opened the Woodland dam to fish passage in 2008 and opened the other dams by 2013. As a result, there's been a steady uptick in fish counts, taken each year at the Milltown dam.
      "In 2023, we counted 841,357 river herring," reported Neal Berry, executive director of the St. Croix International Waterway Commission, during the meeting. "This represents a count that was 18% higher than in 2022. This was the highest yearly count since 1990."
      Along with alewives, last year saw the highest counts of American shad on the St. Croix since counting began in 1981. A total of 675 shad were counted, with the shad counting only taking place during the first 10 minutes of each hour, "meaning that many more shad likely went uncounted," Berry said.
      The river counts took place between April 17 and June 30 last year, with the Milltown dam decommissioning process starting in July. Subsequent fish counts will take place at the Woodland dam using similar methodology as in previous years.

Milltown dam removal nears completion
     The $20 million project to remove the Milltown dam, which was built in 1881 to power a cotton mill on the New Brunswick side of the river, has gone smoothly for the most part. It hit a small snag in December when one of the earthen cofferdams used to expose the riverbed collapsed during a high flooding event, but no injuries were sustained and the project was not overly delayed.
      That's not all there is to the dam's removal, however, as Steve Cooper of NB Power stated. "Knock it down, drag it away, decommissioning the station -- that's relatively easy -- but the fish passageways are a very specialized project."
      Reclaiming the footprint of the mill for fish passageways has been a multi-step process. Excavators constructed a base for fish passage, including a subgrade and a substrate, along with refuge boulders that create roughness and eddies for fish passage. The eddies "really bring online fish passage through the various flows," Cooper said.
      "What we're essentially doing is taking a river that is on a pretty steep slope and removing bedrock upstream and filling downstream to level that slope out," Cooper said, adding that "it's like an upside down road."
      This year, NB Power will be working to remove a concrete stop-log spillway, as well as removing legacy structures on the American side, including old rail trestles, footings, abutments and timber frames. The work is expected to be completed by July or August. Doing so will widen the fish passageway to allow for more fish to swim through.
      On the Canadian side, shoreline restoration will begin this year, with a focus on remedying the artificially high shoreline caused by the cotton mill. "We've got to go back and fix that shoreline because it will have a long-term erosion effect," Cooper said.

Fishways in development
      In addition to building the fish passageway in the absence of the Milltown dam, work is under way to build new fishways at both the Woodland dam and the Grand Falls dam. Sean Ledwin, director of the Bureau of Sea Run Fisheries and Habitat at the Maine Department of Marine Resources (DMR), provided an update on those projects.
      The Woodland dam, located 10 miles upstream from the Milltown dam, has an "outdated fishway that's collapsing with poor fish passage," Ledwin said. To resolve the problem, "we plan to replace the current fishway with two new state-of-the-art fishways" to enable significantly improved downstream fish passage."
      One of the fishways at the Woodland dam will be a fish lift, which is designed to "try to attract [the fish] and then lift them above the dam and then dump them over the dam,' Ledwin said. It's "as large as any in Maine."
      The second fishway will be a fish ladder that "will allow for more, stronger-swimming fish to pass," Ledwin said. Based on a model in Nova Scotia, it's a "bigger secondary fishway."
      The Woodland dam's fishway replacements gained valuable financial support on March 8 with the announcement of $7.8 million in federal funding secured by U.S. Senator Susan Collins. This is in addition to a previous $2 million awarded to DMR for the project through the U.S. Fish and Wildlife Service's National Fish Passage Program. The goal is to finish the design of the project this year and begin construction in 2025.
      At the Grand Falls dam, the DMR is working alongside the Passamaquoddy Tribe to develop "nature like fishways" enabled by the ample room around the river. "We're trying to use a lot of that room to kind of create a sort of a natural channel there," Ledwin said.
      The plan is to build a 3,700-foot long and 30-foot wide passageway similar to the one built on the Presumpscot River, which has proven to be 98% effective for alewife passage, Ledwin explained. Once done, it will be "a pretty bulky fishway that can accommodate pretty significant flow," he said. The Grand Falls design is further behind than the Woodland dam design, with no timetable noted for its estimated construction.
      The end result of enabling greater alewife passage is significant for multiple industries, Ledwin said. "This project overall could provide the largest bait source for the lobster industry," he said, along with producing good paying jobs in the elver fishing industry.
      With the St. Croix producing 60,000 acres of alewife habitat, making it the largest alewife habitat in North America, it could produces "tens of millions of alewives," subsequently producing "hundreds of millions of juvenile fish growing up in the ocean," Ledwin said.
      It's good news for wildlife species, too, including cod, whales, puffins and striped bass, all of which forage on alewives. "They provide a really key ecological function for river watershed and the near shore and ocean ecosystems as well," Ledwin said.
      "This is the largest river restoration project on the East Coast at the moment," Ledwin concluded. "It's a really exciting time to be in fish restoration."