Quebec Municipalities Prepare for Updated Flood Zone Maps Revealing Increased Risk to Properties

Officials in some Quebec municipalities ravaged by past flooding express concerns about potential financial impacts on residents as the province prepares to unveil new flood maps that would significantly increase designated at-risk areas.

Five years ago, a breached dike in Ste-Marthe-sur-le-Lac, Que., forced over 6,000 people from their homes. Residents have faced challenges in rebuilding their lives in the town near Montreal, and Mayor François Robillard indicates that the new flood zone maps are causing more frustration.

“Citizens are currently very surprised… because it will impact their daily lives,” he explained.

Quebec’s current flood maps categorize two risk zones for river and coastal areas—potential flooding within 20 years or between 20 and 100 years. The new system expected in 2025 will introduce four risk categories: low, moderate, high, and very high, each with specific rules for construction and renovation.

For example, property owners in very high-risk areas would not be permitted to build new houses or reconstruct houses destroyed by flooding.

Robillard notes that preliminary maps show 2,000 homes in his town now in flood zones, a significant increase from the current two. This sudden change has left residents confused about the impact on their properties.

“In 2019, when the dike broke causing a flood, the government allowed all affected Ste-Marthe-sur-le-Lac residents to rebuild without flood zone restrictions,” he recalls. Residents believed they were safe with a new dike in place.

“If they had known that four-and-a-half years later we would declare a flood zone… people may not have invested here,” Robillard remarked. “They might have used the government’s funds for reinvestment elsewhere,” he added, criticizing the government’s change of direction as “absurd.”

The Quebec Environment Department did not respond to requests for comment.

In June, the department estimated that with the new maps, over three times as many Quebec residents would reside in at-risk zones, increasing from 22,000 to 77,000 homes. Later, the department indicated a possible downward revision of this figure.

Lake of Two Mountains, just west of Ste-Marthe-sur-le-Lac, is safeguarded by a dike in Pointe-Calumet. With no floods since the 1970s, Mayor Sonia Fontaine notes that the area was not previously classified as a flood zone. However, the updated maps would place over 97 percent of the territory in a flood zone.

Fontaine accuses the province of keeping people uninformed and instilling fear of potential property devaluation.

“Since June, residents are uncertain about their homes here,” she shared. “People are distraught and unable to sell their homes today.”

Both Fontaine and Robillard appeal for the removal of proposed flood zone designations for their towns, suggesting a separate category for protected by dikes municipalities.

Concerns over flood maps have taken a darker turn in the lower Laurentians region. Sylvie D‘Amours, a member of the Coalition Avenir Québec for Mirabel, decided to shut down her office due to safety concerns in October. An incident involving a pellet gun damaging the office window led to speculations on resentment towards the government’s plan to update flood zone maps.

Beauceville, below Quebec City, has also faced floods, like the 2019 Chaudière River ice jam. Town’s general manager Serge Vallée indicates 59 buildings in Beauceville currently fall within flood zones.

“Our fear is that the numbers will rise with the new maps,” he stated, warning that even a low-risk designation could negatively impact mortgages and insurance policies.

Joanna Eyquem, a climate-resilient infrastructure expert at the University of Waterloo’s Intact Centre on Climate Adaptation, emphasizes that poor communication and lack of accessible information have fueled concerns in Quebec.

Eyquem stresses the importance of individuals obtaining flood zone information from not just provincial and municipal bodies but also insurance providers and mortgage lenders, as they possess their own flood zone maps.

While acknowledging the vulnerability of towns like Ste-Marthe-sur-le-Lac and Pointe-Calumet, Eyquem underlines the potential risk of breached dikes that should not be overlooked.