Wawa Mayor Linda Nowicki said Saturday it's expected the southbound stretch of Highway 17 to Sault Ste. Marie, Ont., will be fully reopened by Monday.
The northbound side of the highway could remained closed for another week as crews repair 15-metre holes in the road.
She said the town itself is secure, but that officials didn't have a sense of just how much of a toll the rainstorm took on the area's road network.
"It wasn't until late yesterday and early this morning that we viewed the photographs and realized the scope of the damage," she said.
She said the Michipicoten First Nation, a community that houses 58 people southwest of Wawa, has been completely cut off, prompting an evacuation of a few "vulnerable residents" Saturday afternoon.
"They have no access in or out," Nowicki said.
Emergency Management Ontario said in an email that 18 residents, either elderly and those with medical conditions, were airlifted by helicopter to Wawa.
Nowicki said the rest of the community would be evacuated in the coming days after the band council decided road repairs would take too long to complete.
She said some residents in other areas around Wawa are also isolated, including five homes stranded between severed sections of highway.
Police said phone lines and 911 service in the communities of Dubreuilville, Hawk Junction and Missinabie remain unavailable after connections were severed in the deluge.
Though the rains have ceased, runoff is still a problem and Wawa remains in a state of emergency, Nowicki said.
"It's a pretty gloomy picture for us," she said.
Nowicki said the destroyed road connections have hit businesses hard in Wawa, noting the local economy was already struggling with the loss of forest industry jobs.
"Have you ever heard of a Tim Horton's that wasn't busy busy? Well ours was not today."
She said it came as a shock to see the highway washed away by floods caused by the rain.
"This is a one in a 100 year thing," she said, adding the road was in good condition until the foul weather rolled in.
"This is just a freak storm that lasted too long and came too quickly ... You end up with lakes on the highway."
Nowicki and the municipality said in a release that they are in the process of asking the province to declare Wawa a disaster area, saying damage may total more than $10 million.
The Ministry of Municipal Affairs and Housing said in an email that it was assessing the situation and was in touch with the community.
Meanwhile, a New Democrat member of the Ontario legislature called on the province to come to the aid of the northern community.
MPP Michael Mantha, who represents the area, said the provincial government should be helping repair not only the Trans-Canada, but all damaged roads and bridges.
— By Will Campbell in Toronto.
Note to readers: This is a corrected story. A previous version incorrectly stated that 700 people lived in Michipicoten First Nation.
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