Some 55,000 more homes in Quebec will be in areas at risk of flooding — three times more than today — according to a new generation of flood maps coming from the provincial government.
Quebec officials released the estimates and announced the establishment of a new regulatory framework related to flood zones at a news conference Tuesday.
Although the new maps have yet to be produced, officials expect that nearly 77,000 homes, or two per cent of Quebec’s population, could find themselves in a flood zone compared to 22,000 today.
“In certain places in Quebec, the flood zone mapping has not been updated in 30 years,” Environment Minister Benoit Charette said Tuesday. “We have to update our way of doing things based on the science, and that is what we are proposing today.”
The maps will be produced in collaboration with municipalities in the coming months and will be the subject of public consultations with residents and municipalities this summer.
Currently, Quebec’s flood maps are based solely on the recurrence of floods and are divided into two categories, namely high-risk and low-risk areas – where there is a five per cent and one per cent chance of a flood in any given year, respectively.
The new maps will designate areas of “flood intensity” with four categories: very high, high, moderate and low intensity.
The categories will take into account the frequency of floods, their intensity depending on the water depth reached as well as the impacts of climate change.
New limitations on construction
New regulations announced Tuesday stipulate that repair and renovation work can generally proceed in flood-prone areas, but rebuilding severely damaged structures in very high-intensity flood zones may be restricted.
Expansion in very high-intensity areas will also be limited to essential needs only. Additionally, construction of new buildings in flood-prone areas, even in low-intensity sectors, will not be permitted.
However, municipalities can mitigate risks by implementing flood protection structures such as dikes, which can lead to a reclassification to a lower-intensity zone.
Officials say the objective of the framework is not to relocate residents at risk, but to increase their security and protect their property as well as the environment.