A new report from an environmental nonprofit finds that the southern coast of Massachusetts will see increased flooding and erosion, as well as more destructive shelling from storms. The report, by the Trustees of Reservations, says sea levels along the southern coast are expected to rise by more than two feet by 2050.
The Trustees is the largest private owner of coastal land in Massachusetts, controlling 120 miles of coastline. In 2020, after witnessing increased flooding and erosion on their properties, the group began producing annual reports on the current and predicted effects of climate change on the Massachusetts coast.
Their first report concerned the North Shore; the 2021 report covered Martha’s Vineyard, Nantucket and Gosnold; this year focuses on the 14 south coast towns bordering Narragansett Bay and Buzzards Bay.
Like previous reports, the latest predicts large impacts of climate change on these cities in the coming decades. Here are five takeaways:
New Bedford has a hurricane barrier that works really well. But it won’t last.
After being hit by hurricanes in 1938, 1944 and 1954, engineers built a harbor barrier to protect New Bedford Harbor, the country’s most prosperous fish port. The barrier keeps the water in the port at a level that protects the infrastructure from flooding; when a storm threatens high water, the Genius of the Army closes the gates. In 2019 they closed the barrier 26 times. With sea level rise expected by 2050, they will have to close the reef at each high tide, which means 1-2 times a day.
“It’s clearly not feasible for a functioning port, it’s not sustainable,” said Cynthia Dittbrenner, director of Coast and Natural Resources at the Trustees of Reservations.
The New Bedford Port Authority and the city of Fairhaven are looking for ways to make critical infrastructure in the port more resistant to flooding by lifting, moving or replacing it.
Low-lying cities can expect daily flooding from high tide by 2050.
Over the next 30 years, the sea level along the southern coast is projected to rise by more than two feet. This means that by 2050, more than 25 miles of roads and more than 1,400 buildings in the region will be flooded every day at high tide. Cities with low-altitude critical infrastructure, such as Fairhaven, Falmouth and Wareham, are particularly vulnerable.
Environmental justice communities are particularly vulnerable.
In several cities, flood-vulnerable slums have large numbers of low-income or minority residents, who may not have the money to constantly empty their basements and replace their ruined furniture.
“Municipalities or regional planning associations really need to think about how to prioritize helping those communities that don’t have the resources to do it themselves,” Dittbrenner said.
The cities of New Bedford and Fall River also have large populations of environmental justice – groups that face greater environmental risks due to language barriers, race or income – and while those residents are unlikely to be directly affected by the floods, their livelihoods they could be. The Port of New Bedford, for example, supports approximately 39,000 jobs and generates approximately $ 1.8 billion in total personal wages annually. If the port can’t function, those jobs disappear.
Salt flats protect cities from flooding. But they are drowning.
The south coast boasts 4,900 acres of salt marsh, which filter water, provide wildlife habitat, and act as a storm buffer for the communities behind them. But the swamps on the south coast tend to be smaller than others in the state and are expected to disappear more quickly as they are flooded by rising sea. In addition, years of reclamation and excavation of swamps for agriculture and mosquito control have compressed the ground, so some swamps are sinking as well.
“So at a time when we really want the swamp to do its natural thing of building sediment and building organic matter and climbing higher to keep up with sea level rise, it’s actually sinking,” he said. said Dittbrenner.
The report predicts that 23% of the salt marsh on the south coast will vanish by 2050.
Other states are trying experimental methods such as “mud engines” to strengthen swamps by adding sediment, but in Massachusetts they are not yet allowed.
People are starting to talk about “withdrawal”
Some communities on the south coast are starting to tiptoe towards the concept of “retreat”, permanently abandoning residential areas prone to flooding. “The retreat is a real conversation the city is going to have, and it’s not an easy decision when it comes to people’s homes,” said Jennifer Lincoln, administrator of the Falmouth Conservation Commission, in the report.
Administrators and other environmental groups are supporting state legislation to create a flood protection program, which would buy flood-prone properties, demolish them, and, instead of rebuild, restore the land in swamps or beaches that protects inner neighborhoods. .
A key component of any such law, Dittbrenner said, is ensuring that buybacks are voluntary and that the majority of investments go to homeowners and renters who lack resources, especially those in environmental justice communities.