Chelsey Penrice, who lives in the Muskoka town of Rosseau, told CBC News the problem began last spring, when the ministry installed a liner in a culvert near her home.
The liner narrowed the pipe by 60 per cent, reducing the amount of water and debris it can carry from a local creek under Highway 141 and into Lake Rosseau.
Since then, the creek has overflowed onto the highway and Penrice's home has flooded twice. She and her husband Dave first noticed the waters rising on Sept. 21.
"Panic — I didn't know what to do. We were both running around trying to do what we could do," Penrice told Go Public.
Penrice said that flood caused about $50,000 in damage. Just two months later, on Nov. 24, there was another flood, this one even worse.
"Our entire property was under water. There was water everywhere and the back door was kind of being pushed open because of the water pressure. It had already built up to, I would say, about three feet at our back door," she said.
The couple had recently moved from Halifax and many of their personal belongings were being stored in the basement.
"We had a washer and dryer, a stove, microwave, fridge downstairs, lots of tools, our computers. So we had a lot of personal items that were completely destroyed."
Penrice is still adding up the damage from the second flood, but so far, she said, it's up to $130,000.
"We had to wait for the water to go down until we found ... different cracks and of course our entire property needed to be re-graded. Stuff was everywhere."
Neighbour flooded for 1st time in 13 years
Penrice's neighbour Ed Wiebe has a home built higher up on a slope.
But for the first time since he bought the house more than a decade ago, he was also flooded, in September.
"I've owned my property for over 13 years and [I'd] never experienced any high-level water mark," he said.
Wiebe estimates the damage to his property totals more than $85,000 and said people who live in the area have never seen flooding like this before.
"Obviously you can imagine this is the talk of the town …. flooding out the beach area," he said.
"I talked to some of the elders at the local coffee shop and some that have lived here for more than 60 years, and they've never seen or experienced any water flung over Highway 141."
Penrice and Wiebe say the only thing that's changed is the addition of the polyethylene liner to the culvert. The smaller opening is now getting blocked with debris.
Just weeks before the second flood, Penrice said, she called the area superintendent to ask for the culvert to be cleared of leaves and branches.
Both Wiebe and Penrice have been trying to get answers from the Ministry of Transportation for months, but say the ministry hasn't even confirmed there's a problem with the culvert.
"It's kind of ironic that they just installed the insert [where there had been] no prior flooding, and within six months of that — one flood, then a subsequent second flood," said Wiebe.
Ministry: Liner most ‘economic way’ to repair culvert
The Ministry of Transportation declined an on-camera interview with Go Public, but did answer our questions in an email.
The ministry said it added the liner because the existing culvert needed to be repaired and lining it was "an economic way" to extend the service life.
Spokesman Gordan Rennie said the ministry doesn't know if the culvert is too small for its location, but has hired a third-party drainage engineering firm to assess it.
The firm's report is expected in mid-February. Go Public asked how much the independent report will cost the province, but so far the ministry hasn't answered.
Once the results are in, Rennie said, if required the ministry "will undertake appropriate work to reduce the potential for future flooding."
On mobile? Click here to read the Ministry of Transportation’s full email response to Go Public
Wiebe has also hired an engineering firm to do an assessment. He expects the final report soon, but is already aware of some of the company's findings.
"As we suspected, they had a four-foot culvert [and] it was reduced to two feet," said Wiebe.
"Based on the report coming in, the engineering firm says [it believes] a five- or six-foot culvert ... should be installed."
Province responsible, says ministry, after Go Public inquiries
All this has left Penrice and Wiebe on edge, waiting and hoping there isn't another flood and wondering whether the province would ever take responsibility.
"[It's like the ministry has been] trying to pass the buck to everybody instead of saying, 'Maybe we made a mistake. Let's be honourable about it. Let's correct it and move on,'" said Wiebe.
Go Public made calls to the ministry responsible for deciding who will pay for the flood damage, which Wiebe and Penrice say already totals more than $250,000.
After our inquiries, the Ministry of Government Services' Risk Management and Insurance Services branch told us the province is responsible for the damage.
"In this instance, no other parties are responsible for the incurred damages," wrote ministry spokesman Stephen Puddister in an email to Go Public.
"The government is ready to negotiate settlement of their existing flood claims."
On mobile? Click here to read the Ministry of Government Service's full email response
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