Rallying ‘round the Presumpscot

What does the ideal dam removal and river restoration look like? There’s no such thing as perfect, but the Saccarappa Falls project in Westbrook, Maine, comes close. Not that it was easy…or quick.

“This project has gone on for so long it’s become a way of life for me,” said Michael Shaughnessy, president and co-founder of Friends of the Presumpscot River, who has been advocating for fish passage on the waterway for more than 20 years. “For the last year, I was concerned it wouldn’t happen — right up until the headwall was broken.”

Over the last two decades, a coalition of public and private entities, including the U.S. Fish and Wildlife Service, has worked tirelessly to restore the river to free-flowing, re-opening habitat to migratory fish and expanding opportunities for recreation. Thanks to this 2020 project, migratory fish have access to five more miles of the Presumpscot River…and the community benefits as well.

The Saccarappa Falls site, with new nature-like fishways in both channels of the upper falls and a double Denil fishway under construction along the bank of the lower falls. USFWS

Dams go up; fish go down

From its genesis at Sebago Lake to its confluence with the Atlantic in Casco Bay, the Presumpscot River drops 270 feet over 25 miles. It’s not surprising, then, that the river holds a number of Maine hydropower firsts: first pulp mill in 1734; first dam in 1735; and first hydroelectric dam, 150 years later. With nine barriers impounding 22 river miles, it had more of its “hydraulic head” harnessed than any other river in Maine, into the 21st century.

Alewife is one species of river herring that spawned in the Presumpscot River historically. Chesapeake Bay Program/Will Parson

Blocked from upstream spawning grounds and subjected to industrial pollution from mills, the river’s migratory fish populations declined dramatically over the centuries. By 1900, there were no reported runs of blueback herring and alewife — collectively called river herring — Atlantic salmon, and American shad on the river.

A decades-long endeavor

Things began to turn around for fish in 1996, when flooding at the first barrier on the river — Smelt Hill Dam in Falmouth — damaged the facility beyond repair. With the help of a grant from the National Fish and Wildlife Foundation, the Coastal Conservation Association purchased the broken dam from Central Maine Power. The Army Corps of Engineers and the Maine Department of Marine Resources removed it in 2002.

Also in 1996, Sappi North America began the federal relicensing process for five of the Presumpscot hydroelectric dams — Saccarappa Falls, Mallison Falls, Little Falls, Gambo, and Dundee — it acquired from the S.D. Warren division of Scott Paper Company two years prior. The Federal Energy Regulatory Commission (FERC) regulates non-federal hydroelectric projects and reviews licenses every 30 to 50 years.

The Friends of the Presumpscot River filed a motion to intervene in the renewal process, requesting the first three dams be removed and fish passage installed at the upper two. In 2003, FERC relicensed all five dams for 40 years, with the condition that Sappi build passage for river herring — as prescribed by the U.S. Fish and Wildlife Service — at each one.

Selfie image of man with glasses, grey hair, mustache and beard, River and factory in background
Michael Shaughnessy is president and co-founder of Friends of the Presumpscot River and has been working to free the Presumpscot for more than two decades.

One obstacle remained on the lower Presumpscot: Sappi’s Cumberland Mills Dam a mile downstream from Saccarappa Falls. The dam powered the company’s Westbrook paper mill but no longer generated commercial hydroelectric power, so it wasn’t regulated by FERC.

In 2008, Friends of the Presumpscot River and the Conservation Law Foundation petitioned the state to call for installation of a fishway at Cumberland Mills, citing a Maine law requiring fish passage at dams where migratory fish are documented downstream and their habitat exists upstream. Sappi complied with the ensuing state order, building a fishway in 2012.

The completed Cumberland Mills fishway triggered a requirement for Sappi to provide passage at Saccarappa Falls. Finding construction of a large fish lift financially infeasible, and embracing its commitment to environmental sustainability, the company instead approached the Service to discuss options for surrendering the license.

Through complex negotiations, Sappi and the Service explored fish passage options to meet the company’s obligations under a license surrender. These discussions later included state natural resource agencies, the City of Westbrook, and two stakeholder groups: Friends of the Presumpscot River and The Conservation Law Foundation.

Ultimately, all parties signed a formal settlement agreement to holistically reshape the Saccarappa Falls site by not only providing fish passage but also restoring river function, creating recreational opportunities, and enhancing the aesthetics of the river.

The powerhouse and dams at the upper falls of the Saccarappa site. Maine Preservation

Sappi agreed to remove the powerhouse and both spillways at the upper falls, create nature-like fishways in their place, and build a double Denil fishway at the lower falls. The settlement capped the company’s costs at about $5 million.

In return, Sappi was granted an extension for installing fish passage at the next two dams upriver — Mallison Falls and Little Falls — and released from fish passage obligations at the following two dams — Gambo and Dundee — for the remainder of their licenses.

Smoothing the way for fish

Removing the Saccarappa Falls Dam opens five miles of the Presumpscot River to migratory fish for the first time in roughly 200 years. And, thanks to stipulations in the FERC licenses, that distance will increase in the future.

“Because the fish numbers at Saccarappa Falls will trigger requirements for fish passage at upstream dams, we wanted to make this project good,” said Shaughnessy, with Friends of the Presumpscot River. “It’s highly complex, removing two dams and building both a fish ladder and nature-like fishways.”

Acheron Engineering, in Newport, Maine, designed the double Denil fishway at the lower falls and engineered removal of the powerhouse and spillways. The Fish and Wildlife Service called for the two-channeled ladder to accommodate projected numbers of returning fish.

The double Denil fishway at Saccarappa’s lower falls under construction. Alden Engineering, Barry Stemm

Built into the structure is a fish counter that will track returning fish each spring. Once 2,960 American shad or 18,020 blueback herring pass through in a single season, Sappi will have two years to install fish passage at Mallison Falls.

For the fishways at the upper falls, the river bed was sculpted to look natural and offer resting pools for migrating fish.

Ben Mater, Ph.D, P.E., senior engineer with Alden Research Laboratory in Fort Collins, Colorado, is responsible for that fusion of form and function. He used computerized modeling to study various river flows and their effects on fish migration. Through an iterative, collaborative process, he took the fishways from concept, to design, to construction drawings that guided the contractors in restoring the riverbed.

“It was almost more art than engineering,” Mater said. “We were trying to mimic the shape of the natural channel.”

Left: A computer-generated rendering of the nature-like fishways at the upper falls, looking upstream. Alden Research Laboratory Right: The completed fishways, looking downstream. UFSWS Note the engineered resting pools sculpted into the river bottom.

Because Sappi is required to manage the water level in Sebago Lake, which can store a large quantity of water, periodic releases upstream cause fluctuations in water levels along the length of the river.

“This project was challenging because we were asked to make a river function for fish passage over a wide range of flows,” said Greg Allen, P.E., director of environmental and engineering services at Alden in Holden, Massachusetts.

Gail Wippelhauser, Ph. D., marine resources scientist with the Maine Department of Marine Resources, has been working on fish passage on the Presumpscot since 1996, when Smelt Hill dam was damaged by flood waters.

Through dam removal, fish passage installation, and stocking, the numbers of migratory fish returning to the river have grown over the years, with the highest counts at the Cumberland Mills dam — 52,892 river herring and 55 American shad — occurring in 2018.

American shad is one species of migratory fish returning to Maine’s Presumpscot River. USFWS

The Presumpscot was one of the first river systems with hydroelectric facilities that Wippelhauser worked on. Now nearing retirement, she is gratified to see the Saccarappa Falls restoration near completion and plans in place for upstream passage.

“Twenty years to fix a 200-year-old problem isn’t bad,” she said. “Given the length of hydropower licenses, a fisheries biologist may have only one chance in her career to do so.”

A more natural environment for all

Sean Mahoney, executive vice president and director of the Conservation Law Foundation’s Maine program, emphasized that reopening the Presumpscot over the years has benefited not only fish, but other wildlife and local residents.

“I’ve seen the return of blueback herring and American shad,” he said. “I’ve caught a shad at Presumpscot Falls, while watching osprey circle overhead.”

Presumpscot Falls, where Smelt Hill Dam once stood as a barrier to migratory fish, in the morning mist. Sean Mahoney

He canoes the river and said the trail system flanking it has received lots of use during the pandemic.

“For a century, we turned our backs on our rivers,” he said. “Now people are realizing what a great resource they are; people want to recreate along them.”

David Butler owns and operates Maine Path and Paddle and leads trips down the Presumpscot. He is excited about the newly created rapids at Saccarappa Falls but recommends people scout them before running them.

“While the western channel looks more doable than the eastern one, they both will be challenging,” he said.

The City of Westbrook has embraced the revitalized Presumpscot and plans to expand recreational opportunities as a result of this project. It acquired the island between the two river channels and plans to create a park there, connected by boardwalks to a new riverwalk along the north bank of the river and the existing one on the south bank. A recently constructed pedestrian bridge alongside the vehicle bridge at the base of the lower falls will complete the circuit.

The new pedestrian bridge overlooks the lower falls, shown here with the double Denil fishway on the left. Michael Shaughnessy

“This project greatly supplements our pedestrian amenities,” said Jerre Bryant, city administrator of Westbrook. “It links four parks and forms a walking and biking loop through downtown.”

While residents are excited about the enhancements to the city center, the improvements should also attract more businesses to Westbrook’s repurposed industrial spaces.

“To take a natural amenity and make it a major focal point of downtown strengthens the community from a residential and commercial standpoint,” Bryant said.

Going the extra mile

Barry Stemm, lead engineer at Sappi’s Westbrook Mill, downstream of Saccarappa Falls, said the Saccarappa Falls and Cumberland Mills fish passage projects were built using the best materials and designed to withstand flooding, so they should last long into the future. The projects are also designed to be low-maintenance and guard the safety of employees and the public.

“Sappi has committed over $10 million to construct two world-class fish passage facilities on the Presumpscot River,” Stemm said. “There are less expensive ways to build fish passage, but they would not be as durable or have the best chance of success.”

Before: The western channel showing the decommissioned powerhouse and dam. USFWS After: The western channel with powerhouse and dam removed and nature-like fishway completed. Barry Stemm

Decommissioning a hydropower facility doesn’t always go this way, according to Brett Towler, Ph.D., P.E., fish passage engineer with the Service’s North Atlantic — Appalachian Regional Office.

“There have been instances when licenses were surrendered and communities left with unsightly, deteriorating dams that continue to impact fish habitat and river function,” he said. “As a result of Sappi’s efforts, these barriers have been removed and this scenic portion of the Presumpscot River will serve fish, wildlife, and local residents for decades to come.”

Returning species

In spring 2021, anglers started reporting hundreds of alewife at the base of Mallison Falls dam, the next dam five river miles above Saccarappa. Video from a Maine game warden confirmed fish were passing Saccarappa fishway in great numbers and that river herring had reached the confluence with the Little River, a major tributary of the Presumpscot. For the first time in possibly 120 years, sea-run fish had reached Mallison Falls!

A paragon of partnership

Restoring fish passage is nothing out of the ordinary for the Service. Since 2009, we’ve removed more than 750 stream barriers throughout the Northeast, opening 7,350 river miles and 44,500 acres of wetland habitat. In the last year alone, we took down more than 70 obstacles to fish passage, opening nearly 600 miles and 16,000 acres.

The Saccarappa Falls project stands out, however.

Anna Harris, project leader for the Service’s Maine Field Office in East Orland, credits contributions by all parties for the success of the project.

“This group of partners with varied interests worked together over many years, showing true leadership,” she said. “You don’t always see this type of collaboration. This project could serve as a model for future community development and ecosystem restoration.”

It’s said good things come to those who wait. The Saccarappa Falls restoration proves great things come to those who persevere and work together toward a positive result for all.

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