SAINT JOHN, N.B. -- Canada's defence minister says if the impact of climate change disasters ranging from floods to fires worsens, he may have to increase the number of Canadian Forces personnel available to respond.

"With the impact of climate change, if we see that it's even getting even worse, we'll do a re-evaluation of the numbers that we have," Harjit Sajjan said Monday as he stood next to floodwaters in Saint John, N.B.

Sajjan said there's been a growing need for personnel to help with events such as the current flooding hitting the Saint John River in New Brunswick and many regions of Quebec. He also noted the forest fires that swept through parts of Western Canada last year required military help.

In fact, he said, more Canadian soldiers are currently deployed to domestic disaster relief than to operations outside the country.

The minister spoke while visiting Randolph Island in the Saint John area, where waters from the river rose during heavy rainfall on Saturday.

He said the military has already been increasing its reserves to cope with climate change fallout. However, with the combat training centre in Gagetown, N.B., facing other commitments, the response to disasters could require additional personnel, the minister told reporters.

"We're growing the military to make sure we have the right numbers for our domestic response and to sustain international response as well," he said.

The minister said that climate change has been a security threat for some time, and the Defence Department "looks at climate security challenges around the world." He added: "It is real."

The military response has been welcomed by the public. "It's been great," Norma Knight said after walking through the water flowing across the road to the island.

Days earlier, when the water was deeper, military vehicles enabled residents to leave or return to their homes.

"It's great with the army. They enabled people to go back and forth. Otherwise they're stuck on the island," Knight said, carrying a pair of rubber boots she was taking to her husband.

Knight said she has lived in the area her entire life and had never seen water covering the road until last year's record flooding. She hoped the road could be raised to mitigate flood disruption in the future.

Officials in New Brunswick are urging patience as floodwaters recede in some regions, saying there's a long way to go before the response can become a recovery effort.

"We're still going to see high water for the next couple of days, especially in the southern reaches of the river system," said Greg MacCallum, director of the New Brunswick's Emergency Measures Organization.

Heavy rain caused the river level to rise slightly in Fredericton on Saturday night, but MacCallum said there has already been a discernible drop. He said it will take time for the levels to return to normal along the entire river but said crews will be ready for the recovery phase.

"We will be certain to approach that phase ... with the same energy and determination and thorough planning and execution that we have done for the response," he said.

More than 80 roads across the province remain closed because of flooding, including a major section of the Trans-Canada highway between Oromocto and Riverglade.

MacCallum viewed the highway by helicopter Monday. He said the water is no longer on the roadway, but there is still debris to be removed and inspections to be done. He said that could take a few more days.

-- With files from Michael Tutton in Halifax.