After the Water Recedes: Pierrefonds' Long Road to Rebuilding After the June Flood

On June 20, 2026, a stationary storm system dropped 100–170mm of rain on Montreal's West Island in a matter of hours, flooding 300 to 350 homes across Pierrefonds-Roxboro. Months later, many homeowners are still working through flood damage repair and basement renovation — and figuring out how to rebuild so it doesn't happen again.

  

I've personally met a number of the homeowners affected in the Richer sector and other hard-hit streets, and I'm currently working on several basement renovations in Pierrefonds right now. The story is almost always the same: a family gutting a water-damaged basement for the second or third time, unsure whether it's worth doing properly if the sewers back up again next storm season.

Why the Sewers Keep Backing Up

Residents and engineers have pointed to long-known flaws in the borough's sanitary sewer system as the underlying cause of repeat basement flooding in Pierrefonds-Roxboro. A class-action lawsuit is currently underway against the City of Montreal, the Pierrefonds-Roxboro borough, and Dollard-des-Ormeaux over the issue. Until it's resolved, homeowners are left to protect their own basements — which is where the right flood-resistant renovation makes the difference between a repair and a repeat.

  

Basement Waterproofing & Flood-Resistant Renovation

A flooded basement doesn't have to mean the same basement repair every few years. The materials and methods used in a Pierrefonds basement renovation make a real difference in how it holds up against the next flood:

• Tile with an uncoupling and waterproofing membrane underneath (like Ditra), instead of a floor finish that has to be torn out after every flood
• PVC or composite baseboards and door casings instead of wood, which swells and moulds on contact with water
• A backwater valve installation on the main sewer line, if the home doesn't already have one — the single most effective defence against sewage backing up into the basement during an overwhelmed-sewer event like June's
• A sump pump with battery backup, since most flood damage during a power outage happens exactly when a pump can't run

 

Every basement is different, and the right combination of waterproofing, backwater valve installation, and finishing materials depends on how your home flooded and what your budget allows. You can see typical costs for basement renovation and waterproofing pricing here before booking a free estimate.

Rebuilding After the June Flood, the Right Way

If your basement was one of the 300-plus hit on June 20, you're not alone in still working through it — and given how unresolved the sewer issue still is, this is worth treating as a full flood-resistant basement renovation, not a quick patch. Waterproof it, protect it against backflow, and make sure the next storm costs you a lot less, in money and in time.