A man stuck on an ice floe speeding down the Petitcodiac River this morning reached safety when the ice hit the shore.

A rescue operation was underway as the man, standing on a dirty chunk of ice, passed through the Petitcodiac Causeway gates, under the Gunningsville Bridge and past Chateau Moncton, heading toward the Bay of Fundy on a fast current.

But when the man reached the Dieppe area, he was able to get off the ice patch onto a snowbank. He walked onto dry land and was spotted by firefighters, where he agreed to get help.

Reporters at the scene said the man, who is in his 40s, appeared to be freezing and was being treated by paramedics in an ambulance.

He was taken to hospital and released later in the day, said Sgt. Mario Fortin of the RCMP.

A man stuck on an ice floe speeing down the Petitcodiac River this morning reached safety when the ice hit the shore. 1:18

He said police are still investigating why the man was on the ice in the first place.

Officials didn't release the identity of the man, who was spotted in the river at about 7:15 a.m. It wasn't known how long he was in the river.

A man drifts on the ice near downtown Moncton. (Pierre-Alexandre Bolduc/Radio-Cana)

Division chief Marc Cormier of the Dieppe Fire Department said about 30 firefighters in Moncton, Riverview and Dieppe responded to the scene.

The ice appeared to be a mound, twice the length of the man's height.

Division chief Marc Cormier of the Dieppe Fire Department said about 30 firefighters in Moncton, Riverview and Dieppe responded to the scene. (CBC )

"He was on a large chunk of ice floating with the current," said Cormier.

Firefighters tried to rescue the man by throwing ropes to him from the shore of the open river, but he refused help and they were unsuccessful.

"He's very lucky to still be with us," he said.

The operation took place during rush hour and severely disrupted traffic on some of Moncton and Dieppe's major roadways, including Main, Champlain, Amirault Streets and Acadie Avenue.

Un homme dérive sur la rivière Petitcodiac à Moncton. Les pompiers tentent de le secourir. <a href="https://twitter.com/hashtag/icinb?src=hash&ref_src=twsrc%5Etfw">#icinb</a> <a href="https://t.co/eKaB7x3uKz">pic.twitter.com/eKaB7x3uKz</a> —@nicpelRC

Eric Arsenault, chief of the Moncton Fire Department, said firefighters contacted the Canadian Coast Guard for assistance and fishermen from Alma were heading out on their boats to help.

Earlier in the morning, emergency officials tried to put a boat on the river to rescue the man, but the snowbanks were too high and dangerous. Emergency crews see about six water rescues throughout the year but rarely of people stranded on patches of ice.

Emergency crews are deploying teams to try and rescue the man adrift on the Petitcodiac River. (Pierre-Alexandre Bolduc/Radio-Cana)

"It's dangerous for us because the the tides are obviously a concern, but we have equipment and training for this," said Cormier. "We dropped everything and tried to get him off."

Arsenault said earlier that the man's chances of survival were better if he stayed on the ice floe and didn't end up in the icy water.