NEWCASTLE, Maine — The saltwater marsh behind Marva Nesbit’s home is so beautiful that she constantly is snapping pictures of it. It’s where she takes people when they come to visit. It’s where she goes after a long day. It is her sanctuary.

It also is where Maine Department of Transportation officials would like to create the state’s second wetland mitigation bank, which means changes for Nesbit and 16 of her neighbors who live around the saltwater estuary.

“It is a favorite party spot,” Nesbit said of her porch off the back of her house that faces the 222-acre marsh.

Department of Transportation officials are using eminent domain to acquire buffer zones around the marsh as part of their plans to include the restoration of the wetland as part of a mitigation bank, upsetting Nesbit and other local abutters who are losing access to their land, Town Manager Jon Duke said recently.

“They’re looking to take the rights over the use of the property with eminent domain,” Duke said. “So the people will continue to pay taxes on their properties but will lose access to the land.”

The transportation department is negotiating with landowners about access and financial compensation for taking the land. After the department finishes negotiating with residents, it will present the project to the U.S. Army Corps of Engineers for approval, according to Army Corps project manager Ruth Ladd.

The corps has held a couple meetings recently, including one on June 7 attended by Ladd.

“Most had concerns about their ability to access the marsh,” she said of the 27 residents at the meeting. “There was a misunderstanding about what will be allowed. The key one is they would be allowed to have a path from the nonconservation easement land to the marsh. And if they have an existing dock, they can keep it.”

The wetland mitigation bank proposal also is already linked to a controversial Department of Transportation connector project in Brewer that recently gained federal approval, the town manager said.

“They can use four times the number of acres for a saltwater marsh,” Duke said of the Interstate 395/Route 9 connector that will eventually run through Brewer, Holden and Eddington. “It’s a windfall in their mind. For us, it’s a catastrophe.”

After 16 years of planning, the proposed connector gained its first federal approval in June. The decision clears the way for the Department of Transportation to begin designing the route for the estimated $61 million project and for the right-of-way acquisition process to start.

Maine’s Natural Resources Protection Act authorizes the use of wetland mitigation banks as an acceptable means of compensation for unavoidable impacts to wetlands with construction and development projects.

Sen. Christopher Johnson, who represents District 13, is questioning whether the move makes sense. He added that the affected Newcastle landowners “have been very good stewards to the marsh.”

“It’s not clear whether it’s appropriate policy for DOT to use eminent domain to seize easements, and create a conservation easement that can be banked for a construction project,” Johnson said.

The senator sent Maine Transportation Commissioner David Bernhardt a letter about Newcastle’s concerns, and Bernhardt responded by saying, “The Sherman Marsh bank credits will be used for future Maine DOT projects (25-plus years) in the coastal interior and midcoast biophysical region (i.e. Brunswick to Ellsworth and inland to Waterville).”

“On average, the department will have need for 2-3 acres per year in this region,” Bernhardt said.

“Projects likely to use this credit have not been identified, except for one of the department’s larger projects, [the] I-395-Route 9 connector project,” he said.

Johnson said he would like the credits to be used closer to his region.

“It would be a much wiser policy to protect areas that have the same ecological features, not one that is halfway across the state,” the senator said.

Sherman Marsh is a large salt marsh within the Sheepscot River watershed in the midcoast area.

The number of acres that will be affected by the Brewer-area connector project, designed to ease traffic from the Canadian Maritimes to the federal highway system, is not yet known, so the number of credits needed from the proposed Newcastle mitigation bank are still to be determined.

“We’re in the process of getting it approved,” Dean VanDusen, mitigation and special project manager at the environmental office of the Maine Department of Transportation, said recently of the planned wetland mitigation bank at Sherman Marsh.

“We understand there is a need for the state to acquire property [for wetland mitigation], but we think the question is: How does it benefit the residents of Newcastle and the people impacted?” Duke said of the Brewer project.

There are 17 landowners who have land near the marsh that once was Sherman Lake. The lake was created in the 1930s when an earthen dam was built under Route 1, but an October 2005 storm knocked out the dam and when Department of Transportation officials came to inspect it for repairs, they decided the area should be restored to its natural habitat.

“They drained the lake and reclaimed it as a saltwater marsh,” Duke said. “In 2010, we heard the first rumbling of the DOT trying to acquire this property” for a wetland mitigation bank.

Several restrictions upset Nesbit and her neighbors.

“I was originally told I could not mow past the patio, had to remove my steps to the water, my kayak rack and kayak, and that I could not put it anywhere on my 1,400 feet of shore land,” Nesbit said. “I had to go to the rest stop” to access the waterway.

Now, “DOT has since renegotiated but only verbally,” she said. “Nothing in writing.”

The state currently has a mitigation bank on Sears Island. Authority to create a wetland mitigation bank comes through the federal Clean Water Act and is administered by the Army Corps of Engineers and the Environmental Protection Agency.

The Army Corps issued a request for public comment on the proposed amendment to the Department of Transportation Aquatic Resource Umbrella Mitigation Bank to add Sherman Marsh on Aug. 1, 2013. The agency received only one comment, from the National Marine Fisheries Service, which suggested a 100-foot buffer, according to Ladd.

Department of Transportation officials are going door-to-door to discuss individual buffers with each property owner.

Duke said residents and town officials did not know about the corps’ public comment period.

“The federal agencies are requiring a marsh buffer … to discourage any development,” VanDusen said, adding that Department of Transportation officials are trying to create plans that are ecologically protective while still allowing residents to use the land around their homes. “We’re currently in negotiations with property owners.”

Ladd added, “They’re not getting a 100-foot buffer everywhere.”

Duke said the use of eminent domain is another reason residents are upset.

“The use of the eminent domain process to acquire the land, it’s very difficult for anyone involved to understand,” Duke said. “That’s like killing a fly with a hammer.”