ST. FRANCIS — Anyone who lives along the St. John River knows how fast the water can rise during the spring ice jam season.

It’s a lesson a young Canadian family learned the hard way when their truck became stuck and they were trapped early Saturday evening as the St. John River flooded parts of Route 161 in St. Francis.

“They had apparently gone for a drive up by where the flood zone was,” Gerald Jandreau, St. Francis fire chief, said late Monday afternoon. “We were there monitoring the road after it was closed down because of the high water (and) to keep people from trying to go through, but there was no one to stop them coming down from the other direction.”

Because the road had been closed suddenly, Jandreau said, there had not been an opportunity to place barricades on the western side of the flooded-out section.

Jandreau, who was there with his brother Kenneth Jandreau, Maine State Trooper Adam Stoutemeyer and a handful of river watchers, said he could see the truck coming in their direction and heading right for the water-covered portion of the road.

“When I saw him coming around the curve I thought he would stop,” Jandreau said. “But he must have panicked or thought he could make it and he must have been going 45 or 50 (mph) when he hit that water.”

Jandreau said there was about 4½ feet of water in the road and when the truck hit it, water splashed up into the motor.

“It stopped that engine dead,” Jandreau said, adding he never got the names of the people in the truck.

“We saw them and were like, ‘No, they are not going to go through it,’” Jenna O’Leary, Jandreau’s niece who was there with her uncle, said. “But it just kept coming and then stopped.”

O’Leary said the water was level with the truck’s front bumper and floating trees were striking it.

“Then the lady started yelling she had a baby,” O’Leary said.

That’s when the Jandreau brothers and Stoutemeyer jumped into action.

“When you hear a woman screaming she has a baby, you just go (and) that trooper was getting ready to walk out there in the water to get them,” Gerald Jandreau said. “At first, that water was too deep for us to drive into but the ice had just shifted and minutes later the water was moving back into the river so I took that as a go.”

Jandreau said he told his brother and the trooper to get into the bed of his pickup truck and he slowly backed it up until it was even with the hood of the Canadians’ truck, where he said the water was still waist-deep and about 34 degrees.

“They had a 10-month-old baby in there with them,” Jandreau said. “The trooper took the baby and the young couple climbed out onto the hood of their truck and into the back of mine.”

The entire rescue operation took less than five minutes, Jandreau said.

“We had to do it quick,” he said. “Within a minute, we all could have been under water.”

That’s just how fast conditions change when the ice is running, he said.

“I’ve been living along the St. John River for 52 years,” the fire chief said. “So I have a little bit of experience with ice jams.”

Jandreau said he could not believe anyone would chance driving over a flooded road.

“I guess they were worried about getting home,” he said. “They put themselves in a lot of danger (and) I told them they could have stopped at any house along the river and anyone would take them in for the night.”

After the rescue, Jandreau said he radioed officials in Allagash who sent volunteers to block anyone from attempting to drive through the flooded road from that side.

Earlier that day the Aroostook Emergency Management Agency issued a warning on its Facebook page after receiving reports of people driving around barricades on flooded roads and allowing children to play on the ice floes.

In the early hours Sunday morning, Jandreau said, the spot where the couple’s truck had been stranded was under more than 12 feet of water for a period of time.

Most of the ice has cleared out of the rivers in northern Maine, but parts of the state could see flooding this week because of rain.

According to the National Weather Service, flood watches have been posted for much of the state, with Oxford, Franklin, Somerset, York, Cumberland, Androscoggin, Kennebec, Waldo, Lincoln, Sagadahoc and Knox counties under weather alerts.

Meanwhile, Jandreau said Monday he hoped people would learn from what happened over the weekend.

“Never, ever, ever cross water,” he said. “You might see there is a foot of water, but there could be a 10-foot hole beyond that. Just don’t risk it.”