On the flat, marshy stretches of Maryland’s eastern shore, not a huge amount has changed since Harriet Tubman escaped from slavery here 170 years ago. Rivers and streams lace a wedge of land dotted with wood-board churches and small towns. Crabs and oysters are plucked from the adjacent Chesapeake Bay.

The climate crisis is set, however, to completely transform low-lying Dorchester county, threatening to submerge some of the key heritage associated with Tubman, the celebrated abolitionist whose daring missions helped free scores of slaves from bondage in her homeland.

If planet-warming emissions aren’t radically scaled back then swaths of the Harriet Tubman Underground Railroad national historical park, only established in 2013, will be inundated at high tide by 2050, according to projections by University of Maryland scientists.

A $22m (£17m) Tubman visitor centre, completed in 2017, is set to be severely menaced by the rising waters, the analysis finds, along with several churches connected to Tubman and Joseph Stewart’s canal, where timber was transported from a business that had enslaved her father.

Harriet Tubman Guardian Graphic | Source: Horn Point Lab at the University of Maryland

“Dorchester county is a poster child as to what the rest of the world can expect with flooding,” said Peter Goodwin, president of the University of Maryland Center for Environmental Science.

The county doesn’t rise more than 1.5 metres (5ft) above sea level and is exposed on three sides to the bay, which can act as a funnel to push storms on to the land. The seas could swell by as much as 60cm by 2050, a situation compounded by the fact the land is sinking, a hangover caused by the retreat of ice sheets from the last ice age.

Facebook Twitter Pinterest Visitors look at a mural of Harriet Tubman called Take My Hand, painted by Michael Rosato, at the Harriet Tubman Museum and Educational Center. Photograph: Greg Kahn/The Guardian

“It’s worrying,” Goodwin said. “The county is beautiful but it’s going to look very different. If we can get ahead of things and plan for the future then you can help define what the shoreline will look like. The problem is if you don’t do that then people are going to drift away and the culture will be eroded.”

The situation is causing alarm among those who have highlighted Tubman’s legacy. “These landscapes are rapidly vanishing because of climate change,” said Kasi Lemmons, director of Harriet, a new film based on Tubman’s life. “Losing landmarks such as these underscores the need to protect and preserve the land and our national history for the generations to come.”

Facebook Twitter Pinterest The Harriet Tubman Underground Railroad visitor centre, on the edge of Blackwater national wildlife refuge, which is threatened by sea level rise in Church Creek, Maryland. Photograph: Greg Kahn/The Guardian

Proximity to water for communication, transportation and food has long been intrinsic to Dorchester county but flooding is increasingly chipping away at the routines of day-to-day life. High-tide water lapped in residents’ front yards and is now reaching porches. Carelessly parked cars can end up sodden. School buses struggle to get down roads that are in constant repair. The storms are getting fiercer, as the water and atmosphere warms.

The encroaching tides now also imperil the cultural touchstones of Tubman’s life.

The former slave was born in Dorchester county in 1822 and despite suffering a severe head injury managed to escape to Philadelphia as a young woman. She then helped guide more than 70 enslaved people north to freedom via a network of safe houses and routes known as the Underground Railroad.

Several locations on the Harriet Tubman Underground Railroad Byway, a driving loop of important Tubman sites, are already being eroded, according to Tubman’s biographer Kate Clifford Larson.

Facebook Twitter Pinterest Pastor Darlene Dixon of the New Revived United Methodist church in Taylor’s Island. Photograph: Greg Kahn/The Guardian

“We’re not going to have those landscapes to tell those amazing stories if something doesn’t happen quickly,” Larson said. “In the 20 years I’ve been to these sites I’ve seen them start to disappear because of the water seeping in.

“Some of the roads become impassable and you have to wait out until the water recedes. And some of the precious, really precious, African-American historical and cultural sites are at the most danger right now because they are in the lowest-lying areas.”

Larson frets about where the resources will come to protect places such as the New Revived Methodist church in Smithville, in the heart of Tubman’s former community that often has a waterlogged graveyard. “They are going to need to move the graves and that costs a lot of money,” she said. “It’s frightening how quickly these sites are becoming threatened.”

The Rev Darlene Dixon has only been the pastor of the New Revived for five months but has already experienced being temporarily cut off from her church by a storm that pushed 15cm of water on to the roads and on to the cemetery.

“People are concerned, and naturally I am, too,” Dixon said. “The biggest part of their angst the unknown – which storm, which high tide will cause major damage.”

Dixon said a seawall may have to be erected to protect the church but that may not stop the surrounding community, already one of the poorest in Maryland, crumbling away as the flooding intensifies.

Facebook Twitter Pinterest The Joseph Stewart canal is a seven-mile waterway dug by hand by free and enslaved blacks between 1810 and 1832 as a way to ship timber and other agricultural products to ships in the bay. Photograph: Greg Kahn/The Guardian

“People here have big hearts but there are not many people left in the community because they want to make a living. There’s the fear of the water too,” she said. “We are seeing change occur before our eyes.”

The National Park Service, which oversees the Tubman park, is putting together an assessment of the threats it faces. Deanna Mitchell, the park superintendent, said she reassures tourists that the visitor centre has been built on a relatively elevated piece of land with sea-level rise in mind.

“It’s a beautiful facility and the landscape is beautiful, too,” she said. “Every time I go to work I’m immediately in a mode of reflection. I see that with visitors, too.

“I’m optimistic that we can address whatever comes our way if people can come together on this. We are nine miles away from Chesapeake Bay, which gives us a sort of buffer. But that’s not a cure-all. There’s no way to deny that there’s sea-level rise.”