Note from the editor: This article was shared as part of the series Sinking in Saltwater. It was published by The Maine Monitor and The Portland Press Herald together with help from the Pulitzer Center’s Connected Coastlines reporting project that spans the country. Watch the rest of the show.
Maine’s salt marshes are an important part of the fight against climate change because they protect against storms and soak up emissions that warm the world. These “blue carbon” stores can be 10 times better at absorbing and holding carbon than tropical woods.
Also, marshes are home to many different kinds of plants, birds, and animals, making them some of the state’s most diverse environments.
Researchers from the University of Maine once said that an acre of healthy salt marsh supports a food web that is “more productive than most farmland in the Midwest.”
Many of Maine’s coastal marshes were able to slowly build up their surface over hundreds of years by moving and growing to stay out of the way of rising seas.
But as the world warms, the waves rise faster and storms get stronger, making it harder for the marshes to keep up. And as more land is built on, they don’t have anywhere else to go.
It will depend on what Mainers do over the next 10 years on whether these important ecosystems stay alive, said Beverly Johnson, a professor at Bates College who has studied blue carbon for years, at a Maine Climate Council meeting in December.
Rising seas, coastal development, and polluted runoff are thought to be to blame for Maine losing 28 to 57 percent of its salt marshes by the end of the century. This will have an impact on wildlife and the state’s ability to handle storms.
Now, people all along the coast are working quickly to protect these ecosystems.
Scarborough Marsh is the largest continuous salt marsh in Maine. It is in and around one of Maine’s fastest-growing towns, and roads and house developments are closing in on the higher elevations of the marsh. When the seas rise quickly on the other side, this is where the marsh should move uphill.
Steve Pinette used to be a geologist and is now on the board of the Scarborough Land Trust. This group works with the town and state to try to protect marshland space so it can grow as the ocean gets closer.
He and his coworkers are quietly asking landowners if they would be willing to sell, donate, or give up some of their land so that it can be used as water.
The land trust is also looking into ways to redirect stormwater flow from new developments. This runoff brings extra nutrients to the marsh and helps invasive species grow.
The freshwater flow is making the marsh less salty, sometimes to almost no saltiness, according to Pinette. “There’s a lot of runoff after it rains; it comes from a lot of these subdivisions.”
Conservation groups across the state are also trying to fix the damage that people have done to salt marshes over hundreds of years.
Many of these marshes are blocked by roads or crossed by farming equipment, which messes up the environment and stops water from moving in and out with the tides.
This can make the marsh floor sink, which makes it less able to keep up with the rising water.
Up the coast in Hancock, Maine Coast Heritage Trust’s Tatia Bauer and other marsh restoration experts are digging new ditches in key spots to try to get rid of those clogs.
“The theory is, if you can cover all of this in plants, (with water) flowing in and out properly, a salt marsh can build elevation to keep up with sea level rise,” said Bauer. “But it depends on fixing this plumbing problem.”
Some people say that projects like these should make the marshes in Maine stronger against climate change.