The aging dikes in the Tantramar Marsh along the coast shared by New Brunswick and Nova Scotia have a long history and now they're in need of repair.

Acadian settlers built the dikes in the 1700s and since then they've kept the water from swamping roads and rail links between the two provinces.

But times have changed, and concerns about rising sea levels have the leaders of several municipalities in the area looking to bolster the defences and build up the dikes to combat climate change.

'It's a really complex matter because it's inter-provincial and it's got infrastructure of national importance running through it.' —John Higham, mayor of Sackville, N.B.

"It's really amazing when you look at how these were built so many years ago with just hand tools, they [have] done such a good job for so long," John Higham, the mayor of Sackville, N.B., told CBC's Shift New Brunswick.

"The weather's changed, the water's changed, the infrastructure behind it has changed dramatically and it's reaching the point where those two things are going to collide very soon."

$50M routes in jeopardy

John Higham

Sackville Mayor John Higham says he's spoken with federal MPs from the area about the dikes. (Submitted by John HIgham)

Higham pointed to a federal government report from the Department of Natural Resources to make his point.

In the 2016 report, Climate Risks & Adaptation Practices for the Canadian Transportation Sectorit's estimated the "low-lying route" of road and rail behind the dikes is responsible for roughly $50 million in revenue per day — "a pretty significant item," he said.

A breach disrupting those $50 million veins would be costly, so he's contacted Nova Scotia politicians, David Kogon, the mayor of Amherst, and Allison Gillis, the warden of Cumberland County.

With them, he hopes to set a plan in motion to repair and upgrade the dikes in the marshy Tantramar area.

'There isn't really a clearly responsible party'

"It's a really complex matter because it's inter-provincial and it's got infrastructure of national importance running through it and it hits a little bit of local government," he said.

"There isn't really a clearly responsible party that would have to act on that and I think that that's been the reason that there hasn't been some of this action."

New dikes would likely have to be larger and in higher places, he said, but because it's a marshy area it's tough to speculate where to build them.

Higham said he's met with local MPs and recently contacted the federal government to hopefully start a project or some sort of working group for answers.

With files from Shift New Brunswick