WORKING WITH NATURE:‘Living Seawalls’ project at UMass Boston tests ways to boost resilience

Above, Katherine Dafforn, the director of the Stone Living lab and the co-founder of the Living Seawalls, stands with UMass Boston Provost Joseph Berger in front of the Living Seawall in East Boston at Condor Street Urban Wild. The walls are formed by panels, like the one on the inset, below at right, that mimic habitat features of natural shorelines. The panel, made of upcycled materials, encourages native habitat-forming species like snails, barnacles, and seaweed to live and grow along the built structure.
Cassidy McNeeley photos

Vulnerable coastal communities worldwide are shifting toward nature-based solutions to address flooding and climate change— and a team of people based at UMass Boston’s Dorchester campus are at the vanguard of efforts locally. The university’s Stone Living Lab— led by Australian-born professor Katherine Dafforn— has a team of academics and students testing new approaches to protecting Dorchester’s coastline, the Harbor Islands, and the city itself.

Dafforn, who moved to Boston last winter to take charge at the lab, is an expert in coastal resilience and has developed the so-called “Living Seawall” panels that were installed in Boston for the first time last November.

The panels mimic the natural features of shorelines to create a habitat for native species like barnacles, seaweed, and oysters. The panels can be added to man-made walls and other barriers that already exist or that might be built in the future to prevent inland floods from high tides and storm events.

“Building big barriers is not necessarily long-term, economically better, or more protective,” said Dafforn, who guided The Reporter on a tour of local sites where the panels are being tested. “The Stone Living Lab looked at whether a harbor-wide barrier would be feasible and economical and found that it wasn’t, and that other types of living shorelines, nature-based approaches would actually be a better way to live, protect some of the infrastructure that’s around, and work with nature rather than against it.”

In partnership with the city of Boston and state officials, Dafforn and her team are piloting their “Living Seawall” project at two locations, in Boston’s Seaport and in East Boston.

Dafforn noted that “43 miles of the 47 miles of Boston coastline have seawalls or other sorts of structures and suggested that if they are here for the near term, they could be improved in some way by having more biodiversity grow on them.”

She pointed to what was once a lifeless stone wall in the Seaport’s Fan Pier that becomes greener each day thanks to a cluster of 120 panels installed last November. According to Dafforn, the five panel designs that make up the wall “are all created to provide habitat for the seaweed and the barnacles and the oysters that otherwise don’t have a great kind of place to live on these flat seawalls.

“Some of these designs look a little bit like tide pools,” she explained during a visit last month. “They have been specially designed because tide pools hold water and create this protective space for seaweed that otherwise wouldn’t grow so high up on a seawall.”

She added: “Likewise, without those sorts of swim-throughs, the holes that you might be able to see and some of the other kinds of weathering patterns, like the crevice ledge design, we wouldn’t get some of the things like mussels and oysters landing in those spaces and growing to large sizes because they get picked off by predators.”

While most of the panels are unique in shape and design, some flat ones are thrown into the mix, too.

“Those are our controls because we want to compare the really complex shapes with the flat to show what kind of benefit you get from having this on a seawall,” said Dafforn, who is also supervising a team of UMass Boston students who will continue to monitor the progress of the seawall panels for the next year-and-a-half.

“This isn’t just another research project for the university,” said UMass Boston Provost Joseph Berger. “The Stone Living Lab is one of our top priorities. Because climate change is both an existential threat and because we’re place-based and we’re right on the harbor in Boston, we have a privilege to be there, so then we have a great responsibility.”

He noted that “young people have so much interest, so it’s really important that, starting at the undergraduate level, we’re giving them this type of knowledge. They’ve become more aware of the importance of climate resilience and the things that we need to do as coastal communities to find nature-based solutions to man-made problems.”

The project also makes UMass Boston an innovator in the climate resilience space, thanks in large part to Dafforn, who developed the panel idea and tested it in Sydney, Australia, before accepting the post in Dorchester. This is the first time the seawall panels have been installed in North America, she said.

“One of the interesting things about the Boston installation is that it’s the first time this approach has been tested under freeze-thaw conditions, so we’re not just interested necessarily in what’s growing there, but also can this even survive? Is it tough enough? And it has, which is really cool.”

Dafforn has also discovered that seawalls don’t just vary across continents, but also across neighborhoods. While the Seaport site appears more brown, the test panels installed in East Boston’s Condor Street Urban Wild were a vibrant green when The Reporter visited in mid-June. Standing by the wall during low tide, Dafforn and Berger admired the bright seaweed and abundant sea-life populating the surface of the panels— and also the space behind them.

“We actually set the panels off the wall, usually around three, four inches,” Dafforn explained. “One of the reasons we do that is if you do have an uneven sea wall, it makes it easier to still fit them together, but also it means you don’t have to scrape anything that’s living there. We preserve anything that’s living on the seawall, the back of the panel gets colonized, and then the front gets all the growth that we see — and we survey. “

At the Condor location, students from East Boston High School have been enlisted to conduct research in their backyard. Dafforn wants to observe the two sites for a bit longer before adding any more panels, but in the future hopes many other schools and students can have this same opportunity.

In Dorchester, that could potentially include a Living Seawall project on or near the UMass Boston campus. Flooding along Morrissey Boulevard—the main route to the campus— remains a constant problem that state officials say they will eventually address with a costly project to elevate the roadway with berms and with other seawall features eyed for additional protection. The engineering fixes have been detailed in a report to the Legislature that is expected to be approved by a state-run commission as soon as this week.

One potential solution is a system of ultrasonic sensors— known as Hohonu Overland Flood Sensors— which monitor water levels and predict flooding events. One of these sensors is already in place near Dorchester’s Tenean Beach and can be reviewed at any time through an online dashboard that’s available to the public.

“Three hundred days out of the year, they measure nothing,” said Dafforn, who uses it as a tool in her own work. “Normally, sensors have to be measuring something every day, but most of the year, there is no flooding. Those couple of days where it does happen, we get the ping and we can go and tell people that there might be flooding here.

In the future, Dafforn said, she wants to “propose a nature-based approach that is more targeted toward flooding” to help communities like Dorchester. She added that “holding back the sea is not going to help us out in the long term because we need to work with nature.

“Big issues in Boston are more about shoreline erosion, wave overtopping, and wave energy,” she noted. Right now, the SLL is focused on biodiversity and water quality “but for future installations, we really want to think for Boston what we can do for shoreline erosion and wave energy as well.”

While Dafforn doesn’t yet have all the answers, she says her work can reduce the sense of doom and gloom that so often is associated with climate change and rising sea levels.

“It brings a bit of hope, we’re not just talking about the problem, but hope through innovation as well,” she said.


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