Portland, South Portland, and the Portland Harbor Commission submitted an application last month for a $24 million federal grant to help fund the dredging in 2024 of contaminated mud from around the piers, wharves and berthing areas in Portland Harbor – a milestone in a decades-long collaboration between municipalities, government agencies, waterfront businesses, and environmental organizations.
“This has been probably one of the most collaborative projects I’ve ever worked on,” commission Chairman Dan Haley said. “Environmentally and economically it’s just a win for everybody. … It was great to bring everybody into the fold and all go forward as a united front.”
The persistent presence of toxins in the sediment around wharves and piers from an era of heavy industry on the harbor has far-reaching economic and environmental implications that affect the sustainability of the working waterfront and island communities, and has made maintenance dredging prohibitively expensive for property owners.
Resuspended toxic sediments, stirred up by boat propellers and storms, impact the clean water on which the lobster and aquaculture industries depend and affect the health of the Fore River estuary. As sediments build up, the piers and wharves lose berthing depth so boats can tie up and do business in smaller and smaller windows around high tide.
The same is true at the East End public landing, where emergency or maintenance vehicles must wait until two hours after low tide to board barges to the islands. As marine space is lost in the harbor, owners must turn to other uses for revenue such as office, retail, and restaurants.
“These are existential issues for industries,” said Bill Needelman, Portland’s waterfront coordinator. “If they lose water depth, they no longer function, and we would have no choice, as a community, but to accept the diminution of the working waterfront in replacement with other uses.”
Charles Poole, owner of Union Wharf, said May 24 that he would like to have his pier dredged to 20 feet at low tide and the areas at the top of pier dredged just to 5-10 feet, so lobster boats can tie up. But the biological assessment required for disposal at sea of the sediments around his property alone would cost him $70,000-$80,000. Disposal of dredged materials at federal ocean disposal sites requires biological assessments before a disposal fee is assessed.
Recognizing the impossible situation for pier owners and the need to clear public berthing areas, Portland, South Portland, and the harbor commission have been seeking public funding to tackle the problem. The latest and most ambitious effort was the submission May 14 of an application for a Better Utilizing Investments to Leverage Development, or BUILD, grant from the U.S. Department Of Transportation, to cover $24 million of the $29 million cost of dredging.

BUILD requirements stipulate that for urban areas, 20 percent of the project costs must be covered with local matching funds. The Maine Department of Transportation has agreed to cover half of that, or $2.99 million, and the rest would be paid in tipping fees by the cities and private owners based on the amount of material dredged.
“Those private dollars that we’d be looking for are leveraging a great deal of public money,” Needelman said, “in recognition that … the pollution that has created the greatest barrier for dredging is largely coming from either natural public sources or historic legacy contaminants that are not the fault or cause of current owners.”
Much of the contamination came from a time when heavy industries including sugaries, canneries, manufacturing facilities and coal facilities were on the Portland waterfront or on piers and wharves themselves. Further up the Stroudwater River were coal gasification plants. These left a legacy of contaminants including PCBs, DDT residues, metals, and burnt and partially burnt hydrocarbons.
The Casco Bay Estuary Partnership, formed in 1990 when Casco Bay was designated an “estuary of national significance” in the U.S. EPA’s National Estuary Program, has been concerned about toxins in Portland Harbor since its inception and has been surveying contamination throughout the bay since the early 1990s. Such contaminated sediments would not meet federal standards for disposal at sea, so in 2007, it convened a Portland Harbor Dredge Committee and commissioned a study to compare disposal options for the toxic sediments.
It found that an innovative method, Confined Aquatic Disposal, would be the most cost-effective option.
This involves digging a pit in the ocean floor (a CAD cell) near the dredge site, depositing the dredge material there, and covering it with sand. It is then capped with a biological layer naturally over time through deposition. This method has been used around the world, and there are 11 CAD cells in Boston Harbor, which has similar geology to Portland Harbor. The Portland dredge would be the first use of a CAD cell in Maine.
Portland and South Portland formed a working group in 2014 to explore alternative disposal options and came to the same conclusion.
Eventually a spot at the mouth of South Portland’s Mill Cove, between the Casco Bay Bridge and the U.S. Coast Guard station, was selected for the CAD cell.
Director Curtis Bohlen said the estuary partnership was involved in the cities’ discussions about the disposal of dredge materials and he felt they and the harbor commission did a good job of vetting alternative sites for a CAD cell and anticipating engineering problems.
“You know, you’re digging a giant hole in the harbor and dumping toxic stuff in it,” Bohlen said. “It’s not risk-free, but this is better than the alternatives in a lot of ways, and I think on balance it is a positive for the harbor.”
Environmental activist group Friends of Casco Bay also supports the project even though dredging is disruptive to ecosystems.
“For the health of the bay and for the health of the bottom habitat – the benthic habitat – (we) very much would love to see those sediments removed from the harbor,” Casco Baykeeper Ivy Frignoca said.
She said the Friends group has been involved in selecting a site for the cell, along with local lobstermen.
“We have found the Portland Harbor Commission and the two cities are very receptive and responsive to our concerns, and the concerns of the fisherman,” Frignoca said. “(They) worked very hard to choose a site that was going to have the least environmental harm and have the most environmental benefit.
She met with the Portland Harbor Commission to review the CAD cell permit application, and she said the commission agreed upfront to “common-sense” permit conditions, such as not dredging during rough seas, to minimize the risk that contaminated sediments will be dispersed in transport.
Needelman said that the dredging would be done only in winter, to limit impacts to marine life.
The Friends group is also working to eliminate pollution from combined sewer overflows and stormwater discharge so that once the legacy contaminants are removed, new contaminants are not introduced.
In 2015, Maine DOT allocated $250,000 to Portland to fund the design and permitting of a CAD cell, and Canadian engineering firm Stantec was awarded the contract for this work. That year the Portland Harbor Commission also received a $350,000 federal Brownfields grant for environmental site assessments of the sediment floor of the federal channel adjacent to the city’s wharves, and the commission hired Campbell Environmental Group of Falmouth to complete the design and permitting for the dredging portion of the project.
“That grant allowed the permitting to start happening, not on the shoulders of property owners,” Poole said. “So that was huge.”
Using a CAD cell brings projected dredging costs down to $40-$55 per cubic yard, from $145-$215 per cubic yard for landfilling the material, according to the BUILD grant application.
An estimated 244,000 cubic yards of sediment would be removed from either side of the Fore River. Of that, nearly 52,000 cubic yards is on property owned by the city of Portland and about 2,300 cubic yards is on South Portland public property, while the rest is on private property at 32 private piers, boatyards, and marinas in both cities.
The advance of the coronavirus could not delay the grant application process – the May 18 application deadline was set by Congress in the Fiscal Year 2020 Appropriations Act – and despite the financial impacts of the pandemic, the two cities are still on board.
The application includes a May 6 letter from Portland City Manager Jon Jennings that commits Portland to provide $1.3 million in matching funds, and a May 13 letter from South Portland City Manager Scott Morelli committing to its share of the matching funds, without providing a dollar amount. Needelman said he is confident that the pier owners, too, will continue to see the value in participating.
“Reaching our participant pier owners, while their businesses are in flux and sometimes, in some cases in chaos, certainly has been a challenge,” he said. “We had no choice but to ask one more thing of these pier owners and property owners, which was to take time to understand what the commitments are.”
South Portland hosted an online meeting with property owners in early May to let them know what the financial commitment would be if they participated versus what it would cost to go it alone, and what kind of financing would be available when the bill comes due in a few years after the CAD cell is built. The tipping fee would be affected by how many private property owners participate and how much total material they plan to remove.
Twenty-two pier owners and waterfront businesses wrote letters of support to accompany the BUILD grant application.
Rob Soucy, President of Port Harbor Marine, wrote that his father built a small marina on an abandoned fish cannery on the South Portland side of Portland Harbor in the 1970s and the Spring Point and Breakwater marinas have grown substantially since that time. Without dredging in the next few years, he wrote, continued siltation would have a devastating impact on his business because it would make the channel to the marinas completely impassable at low tide.
Poole, at Union Wharf, said that some may consider the estimated $15-$20 tipping fees expensive, but he thinks it’s worth it.
“We are full-on, totally, 100 percent supportive of the effort,” he said by phone May 24. “This railroad train is only going to go by so many times. Right now, this is the window to get on. My feeling is it’s worth it to get it done.”
At Casco Bay Estuary Partnership, Bohlen said the dredging project did not create the collaborative community around the harbor, rather it reflects the strong ties that the environmental interests and the economic interests in the area have built over decades.
He pointed to the Waterfront Alliance of Portland and South Portland, which has provided a venue where people with different connections to the bay could talk about waterfront issues and dredging in particular and bring up their concerns early on, rather than raising objections through public comment once a project reaches the permitting phase.
“We have people who run marinas, and people who own piers, we have folks who worry about safety in the harbor, we have people who represent the Casco Bay Lines,” Bohlen said, “and we’re all in the room together. It’s a part of the culture of Portland Harbor that this is a respectful and collaborative group who wants to find solutions together.”
The CBEP is continuing to be a part of the conversations, to help ensure the dredge is done in a way that is environmentally responsible while achieving economic goals.
“If you want people to care about the bay, one of the ways to do it is to make sure you can make a living on water,” he said, noting that having an actual working waterfront is a crucial part of Portland’s unique character. “It’s not like there’s a negative here between economics and the environment; they’re both pulling in the same direction for us.”
“We need to have an economically vibrant waterfront. Well, how do we do that? This is one way to move that forward.”
A decision on the BUILD grant application is expected in August.
Plan would mitigate impact on essential aquatic plant
The Portland Harbor Commission has developed a plan to mitigate the impact on eelgrass from a planned dredging project by requiring the use of moorings that do not destroy plants on the ocean floor.
Eelgrass is an aquatic plant that grows in underwater meadows. It serves as a nursery habitat for many marine species, improves water quality by filtering out sediments, absorbs excess nutrients from stormwater runoff, increases dissolved oxygen, and absorbs and sequesters carbon. It may also reduce ocean acidification.
Casco Bay lost 58 percent of its eelgrass – more than 5,000 acres – between 2002 and 2013, according to a study by Seth Barker for the Casco Bay Estuary Partnership and Maine Department of Environmental Protection. Most of the loss occurred in Maquoit Bay and Middle Bay, near Brunswick and Freeport, while the area from Portland Harbor to Great Chebeague Island had the most eelgrass, with an increase of 24 acres.
The dredging project planned for 2024 would impact about an acre and a quarter of eelgrass. Maine wetland protection rules call for impacts to eelgrass habitat to be compensated by a 2-1 ratio, which would require 103,600 square feet for this project.
In its application to the U.S. Army Corps of Engineers and Maine Department of Environmental Protection, the harbor commission originally proposed to pay a fee in lieu of mitigation. However, the National Oceanic and Atmospheric Administration and the U.S. Environmental Protection Agency raised concerns that the fee program has not funded any eelgrass restoration projects in its 12 years of existence.
“They’ve never had an eelgrass restoration project,” Mike Johnson, a marine habitat resource specialist at NOAA, said. “And that’s the whole purpose of the in-lieu fee program – to offset the impacts from individual projects.”
The in-lieu fee program was established in 2008 as a way to have permit applicants compensate for the impacts on wetlands and other aquatic resources, including eelgrass beds.
The Maine DEP and the Army Corps of Engineers run the permitting side of the program. They assess fees according to the extent of the impact. The DEP collects the fees and has an agreement with The Nature Conservancy to administer the fund, called the Maine Natural Resource Conservation Program. Funds are distributed to conservation projects through an annual grant cycle; this year’s opened June 1.
Bryan Emerson, mitigation program manager at The Nature Conservancy, confirmed the program has never funded any eelgrass mitigation or restoration projects because the program had never received any proposals for such projects.
But he said the overall impact to eelgrass permitted through the in-lieu fee program has been small. Over the course of the program, 16 projects were permitted that impacted 8,000 square feet, or less than 0.2 acres. He said these projects – mostly piers, docks, and floats – were a mix of direct and indirect impacts, such as shading of eelgrass.
While the aim of the project is to fund in-kind mitigation, Emerson said, the agreement with DEP allows some flexibility because some resources are harder to mitigate than others. The program tracks the impacts and the conservation projects funded by resources and region, and bases funding priorities on these metrics each year. This year, the priority is for coastal wetlands projects.
“(The Maine Natural Resource Conservation Program) is in need of projects that restore, enhance, or preserve coastal wetland resources (e.g., salt marsh, mudflats, eelgrass, subtidal habitats, etc.) in order to compensate for recent impacts to these resources,” the program’s grant application web page states.
Johnson suggested the reason no one has applied to fund eelgrass restoration is that eelgrass restoration is difficult. A site must be found with the right conditions for eelgrass to grow, individual plants must be transplanted from healthy beds and anchored in the substrate, and the restoration site must be monitored.
“I don’t fault people for being concerned or being wary of eelgrass restoration,” he said. “But we have to keep trying.”
Emerson said that other factors such as disturbance by green crabs and water quality changes can affect the success of eelgrass restoration. He said part of his job as manager of the program is to do outreach about areas or resources for which projects are lacking.
“I think that there’s a need for more mapping, modeling, and research on it as well, so that’s something we’re trying to work with our partners to understand,” he said. “But we can only approve what gets submitted, so we can only do so much.”
After Johnson and an EPA biologist raised their concerns about the in-lieu fee, the Portland Harbor Commission held a meeting in February with representatives from the U.S. EPA, US. Geological Survey, National Marine Fisheries Service, Maine Department of Marine Resources, the DEP, and environmental groups to discuss other options.
On May 20 the commission proposed a plan to meet the mitigation requirement by converting traditional block-and-chain moorings in eelgrass beds to conservation moorings, or by moving the moorings outside of the beds. Conservation moorings are moorings that do not have chains or tackle that scrape the ocean bottom, but instead use buoyant lines to connect the boat to an anchor.
When the chains of traditional moorings drag along the ocean floor in an eelgrass bed with the rise and fall of the tides, they rip up the delicate aquatic plants around the mooring block. These scars can be seen in aerial photographs.
The scars average 437 square feet per mooring, according to an analysis of aerial photographs of 26 moorings in eelgrass beds in Casco Bay conducted by the city of Portland and Stantec, the engineering firm for the dredging project and author of the mitigation plan.
There are a total of 245 moorings in eelgrass beds where the Portland Harbor Commission has jurisdiction: at the East End, Willard Beach, Spring Point, Cliff Island, Peaks Island, Cushing Island, Great Diamond Island, and Little Diamond Island. The mitigation plan calculates that using the average scar measurement, converting all of these to conservation moorings could restore more than 107,000 square feet of eelgrass.
The dredge will impact just under 1 acre of an eelgrass bed at the East End barge landing in Portland and about a quarter of an acre at Spring Point Marina in South Portland, for a total of nearly 52,000 square feet. The 2-1 mitigation rule would require 103,600 square feet to be restored.
Commission Chair Dan Haley said the mitigation plan came together quickly after the meeting with eelgrass experts.
“It has been pretty interesting,” he said. “I’ve learned a lot about eelgrass, and I never gave a thought to it, as you know most people don’t. It’s been a good learning process.”
Haley said new moorings are now required to be conservation moorings, and by 2024, when dredging in eelgrass beds is expected to begin, all the moorings will have to be converted or moved out of the beds. “We’ll be kind of a trendsetter for the rest of the area,” he said.
If not enough moorings have been replaced at that point to meet the mitigation requirements, they will pay an in-lieu fee to cover the gap.
NOAA’s Johnson said he thinks the mitigation plan is “a reasonable approach.”
“I have to give the city of Portland some kudos and some benefit of making an attempt,” he said, although he noted there are a lot of unknowns about the project, including whether the permit turnover represents different moorings each year. “We’re hopeful that it does work out, but there’s a risk.”
A similar mitigation plan was put in place in Boston Harbor for impacts to an eelgrass bed from the extension of a runway at Logan International Airport and monitored over four years. Johnson said the monitoring revealed that the project was “kind of a mixed bag.”
The studies found that the moorings need to be cleaned seasonally, and in some cases monthly, because when they become fouled with algae they lose buoyancy and scrape the bottom anyway. The study also found that the moorings must be sized correctly for the location or they will not reduce impacts to eelgrass.
“We are requiring them to report each year on their progress,” Johnson said of the Portland Harbor Commission’s plan, “so after four years, we’ll have an idea of how well it works and whether or not we want to continue to take that approach in the future.”
— Jordan Bailey