SAINT JOHN, N.B. -- Officials are issuing a fresh warning to flood-weary New Brunswickers even as the record-breaking floodwaters that have swamped homes, washed away cottages and submerged dozens of roads begin to retreat.

"The threat is not over," Greg MacCallum, director of the New Brunswick Emergency Measures Organization, said during a briefing Tuesday.

"It's not time to let anyone's guard down," he said. "It's still an emergency situation in some areas."

MacCallum said anxiety is high in the flood zone, but he urged patience and vigilance. The effects of the historic flood could linger for weeks and months.

Although the swollen Saint John River has crested and water levels are receding, the fast-moving, contaminated waters continue to pose a danger.

Geoffrey Downey, spokesman for the EMO, said there is raw sewage and motor oil in the river, animals have likely drowned in it and there have been reports of propane tanks going down the river and discharging their contents.

"There's any number of contaminants in the river right now," he said.

Floodwaters could contain harmful bacteria like salmonella or E. Coli, officials said.

"You need to avoid contact with flood waters," the province's chief medical officer of health, Dr. Jennifer Russell, said. "Water contaminated with sewage may carry bacteria that can make propel sick."

For residents cleaning contaminated areas, she said protective clothing including gloves, masks and boots should be worn and hands should be washed regularly.

Children and pets should not be allowed to play in floodwater, Russell added, and toys submerged in the floodwater should be washed in hot water and disinfected.

Downey said water levels from the swollen Saint John River had decreased Tuesday by about 30 centimetres from eight metres to about 7.7 metres in Fredericton.

In Saint John, the levels were at about 5.6 metres -- a drop of about 10 centimetres from Monday.

"I'm hopeful we're on the way back to normalcy," Doug Britton, 71, said Tuesday as water crashed over sandbags outside the window in his now-empty basement near Quispamsis, N.B., outside Saint John.

Britton's hot tub drifted away from under his deck a few days ago, and is now floating metres away. Hundreds of sandbags are lined up against the back of his house.

Britton, who estimates the water level is roughly three metres higher than usual, has been feeding gasoline to four water pumps every hour to ward off floodwaters from the Kennebecasis River. He also has to clean debris from the pumps every 15 minutes.

"It's hard to believe the power of water," said Britton over the sound of his pumps shooting large streams of water away from his two-level house. "But knock on wood, we might just be able to make it through this."

A couple whose sandbag-lined home is next to a washed-out road in Saint John, N.B., had set up a table at the end of their driveway Tuesday to distribute bottled water and snacks to smiling passerby.

In nearby Rothesay, N.B., some residents were forced to park at the end of their flooded street and don hip waders before making the trek in rubber boots to their homes. Ducks were swimming in the front yard of a deserted-looking house on the road that borders the Kennebecasis River.

Danielle Ring, 23, and her sister Rebecca, 20, were on cleanup duty Tuesday in the flooded front lot of their father's boat service business, Brothers Cove Ventures, in Saint John, N.B. The sisters were shovelling debris and wading through flood waters to retrieve floating wood pallets and other rubbish.

Dozens of boats had to be moved up towards the street and into neighbouring driveways away from flood waters that inched up hundreds of feet from where the shoreline normally sits.

Danielle Ring said they are exhausted, but are happy the family was spared from more serious damage.

"It's a lot on the body. You're using every muscle -- lifting, pushing. The sand-bagging was the worst," said Ring, holding a shovel and wearing hip waders, rubber boots and gloves.

"But this is what you get when you live next to the water. You take that chance."

With no significant precipitation in the forecast, a provincial official said floodwaters should continue to decline in the coming days "barring a very large rain event."

"Water levels in the lower Saint John River basin from Fredericton all the way down to Quispamsis and Saint John have all declined slightly and they will continue to slowly decline," said Jasmin Boisvert, a water resource specialist with the Environment Department.

Meanwhile, the Trans-Canada Highway remains closed between Fredericton and Moncton.

It's unclear when it will reopen, with reports of significant debris buildup along the highway, Jules Michaud, executive director of operations with the Department of Transportation and Infrastructure.

"The highway will reopen following any remedial work that is required to ensure that he highway is safe," he said. "We anticipate the highway will initially reopen with one lane in each direction."

The highway is one of about 150 roads impacted by the deluge province-wide, with about 85 of those closed or partially closed. Another 65 roads are being closely monitored.

The numbers continue to fluctuate and officials urged motorists to heed road warnings and barricades.

Roughly 1,275 people have contacted the Red Cross indicating they have evacuated their homes, while others left but did not register.

The province also said Tuesday that it is looking at options when it comes to compensating people whose recreational properties sustained damage. Downey said nothing had been decided as of yet, but confirmed that officials are considering the possibility of offering assistance to cottage owners.

-- With files from Alison Auld and Brett Bundale in Halifax.