Municipal engineers in Saint John fear a section of Sand Cove Road could collapse cutting off homes and access to the popular Irving Nature Park.
City staff also delivered letters to homeowners in the area telling them they would be "well advised" to hire experts to assess the "structural integrity" of their homes.
A section of the shoulder of Sand Cove Road near McLaren's Beach has fallen away, the city responded by putting up barricades closing the westbound section of the road to vehicles.
"We don't want traffic next to the bank because it's that unstable that it's not safe," said Coun. Bill Farren.
"There's a lot of land movement there."
'They say it's going to happen.' - Bill Farren, city councillor
Farren says the city has hired an engineering firm to monitor the situation, but both consultants and municipal staff are in agreement Sand Cove Road in that area will eventually collapse entirely.
"They say it's going to happen," said Farren.
"There's no quick or cheap remedy to this at all."
The Ward 1 councillor says one possible option identified by city staff is to reroute Sand Cove Road to the north, around Greenwood Cemetery.
A second option is to find a way to shore up the slope.
Farren says he prefers the city look at that because it would help protect homes threatened by further failure of the slope.
In the meantime, residents in the neighbourhood plan to form a community group to press for a solution.
Willa Mavis' home remains stable, but a brick fireplace in her backyard dropped almost two metres last winter.
"And that's in one year, from when we got snow in November until the snow was gone in May," said Mavis. "We looked out and our land was completely changed."
"There's 10 families that are in jeopardy of losing their homes at this point. Right now, we're all being billed and taxed for very expensive waterfront homes."
Mavis believes a stone breakwater along the beach would shore up the slope.
She says that worked for much of Sand Cove, to the west of McLaren's Beach, when a local contractor built a breakwater in the 1950s.