Salt marshes, bluffs, and rising sea levels

Thu, 04/23/2020 - 6:00pm

“I have lived in Rhode Island for one week when I set out to explore the nearest tidal marsh, the landscape I know will be the first to show signs of sea level rise... It is no surprise, then, that 15 percent of Rhode Island is classified as wetlands. And of that 15 percent, roughly an eighth is tidal, both one of the most nimble types of ecosystem in the world and one of the most imperiled. Over the past two hundred years, Rhode Island lost over 50 percent of its tidal marshes to the filling and diking that come with development. Today the remaining fields of black needlerush and cordgrass are beginning to disappear thanks to higher tides and stronger storms.”

Author Elizabeth Rush opened her Facebook live event by reading from the first chapter of her book, “Rising: Dispatches from the New American Shore,” which discusses the tidal marshes found at Jacob’s Point near Narragansett Bay.

On Thursday, April 2, the Pell Center for International Relations and Public Policy, in collaboration with the Rhode Island Center for the Book, hosted a live Facebook discussion with Rush. She was originally scheduled to speak in person at Salve Regina University in Newport, but with the nation taking safety protocols into consideration, the discussion was moved online.

Rush, currently based in Providence and a professor at Brown, captures intimate stories and portraits of coastal communities in the United States, communities that are vulnerable and have visible impacts from climate change, specifically due to sea level rise.

Island resident and conservationist Keith Lewis has spoken highly of Rush’s research on coastal communities and the effects of sea level rise.

“We met Elizabeth and her husband in 2018 when the Block Island Maritime Institute (BIMI) invited her to speak about her book. Because of Kay [Lewis]’s connections with Brown University — where Elizabeth and her husband both teach — we were asked to host the couple. The relationship ‘clicked’ and that was the beginning of a neat friendship.”

In a phone interview with Rush, The Block Island Times asked about her thoughts on sea level rise and the impact on salt marshes. Block Island has its own salt marshes: coastal wetlands that are flooded and drained by saltwater brought in by the tides.

“We know from the past, salt marshes can adjust to some changes in sea level,” said Rush. She stated that salt marshes can “migrate up and in” on land… [but] at the rate at which sea level rising accelerates, we are seeing marshes being outpaced by sea levels,” she said.

Human development abutting salt marshes can impede marsh’s ability to adapt to sea level rise. The marshes “become squeezed between the developments and sea levels,” said Rush.

“Fifty percent of the endangered species in the United States rely on wetland ecosystems (salt and freshwater)... and are just as important as the Amazon, providing homes to the animals and plants,” says Rush. She also noted marshes are “incredible carbon sinks... productive spaces that grow every year, [and] help control carbon intake.”

Block Island also has fragile bluffs — cliffs overlooking the Atlantic Ocean — on all sides. Bluffs on the island have faced challenges as well from sea level rise, including erosion and underground runoff.

“Definitely a thing — there is a lot more to the bluff erosion,” which has been seen through the increased underground streams and water runoff through the bluffs, and the wave erosion from the higher rates of storms, said The Nature Conservancy Associate State Director Scott Comings.

“I remember back to the ‘70s, and there has been pronounced erosion since then,” said Comings.

Comings added, “Black Rock to the Southeast Light has taken the most beating. Erosion is more pronounced because of the bluffs. On West Beach, there is a four-foot drop from the dunes by the North Light . . . [and by] Clayhead, we had to cut back the trail along the bluff. The Mohegan Bluffs has the most dramatic change we have seen.”

Comings stated the areas on the island that have received the most attention include Spring Street, Corn Neck Road, and the transfer station.

The Nature Conservancy in Rhode Island is currently testing “mitigation practices to allow vegetation to come back and mitigate wave pressure and current, and to create land,” said Comings. The testing will be conducted in Rhode Island, and “if it works on the mainland, we might test it out on the island in the future,” said Comings.

“We need to monitor and understand the current problems we have... develop an understanding [and] if erosion rates are accelerating,” said Comings.

Rush said she is also seeing continued erosion along bluffs. Damage in some coastal communities has been devastating: “You see houses tumble into the sea due to bluff and cliff erosion, and active relocation of developments and historic sites,” she said.

While climate change and its lingering impacts are a current issue in coastal communities, it’s important to seek positive and sustainable change, and how to share our voices in our communities.

“We need to think and act collectively. Focus on change and [how] to join a voice. Find people who share your passion. Don’t lose sight of what you are fighting for,” said Rush.