Sunday night’s supermoon has created some of the highest tides in the Bay of Fundy in almost two decades.

And now with as much as 150 millimeters of rain predicted to hit much of New Brunswick, people living in low-lying areas are concerned about flooding.

Mike Carr is with the Saint John Fire Department and manager of EMO. He says city crews are already busy at work clearing storm drains and preparing for Wednesday’s rain.

"We're not worried about river flooding, but we are worried about localized flooding and the places in Saint John that regularly get flooded are going to be susceptible, obviously if we do get what's forecasted," he said.

Saint John fisherman Chuck Breen says he’s not worried for his location, but some areas along the St. John River may be at risk.

“We'll have to wait and see,” he said. “It's supposed to rain 100 millimeters or whatever so if it does you might have some flooding then."

Kyla Weston, who works at a campground along the Bay of Fundy, says with the heavy rain in the forecast, they will be moving campers further from where they usually set up their tents.

"This time of year we don't have a lot of campers so we're not too worried,” she said. “We can put people in the upper part of the campground and they'll be safe and relatively dry.”

Tourists captured what they could of the dramatic rising waters on Tuesday, with local residents passing along words of caution.

"The lady at the information centre said we be very careful driving back because the tide could be over the road by now," said one tourist.

There have been no reports of flooded roads yet, but emergency crews say that could change quickly.

With files from CTV Atlantic’s Ashley Blackford.