Emergency basement flooding calls across Mississauga, Brampton and west Toronto have climbed sharply since Friday morning, according to DrainCom Inc., a licensed waterproofing and drain repair company that has served the Greater Toronto Area for more than 20 years.

Credit Valley Conservation issued a flood outlook statement on August 6 covering Mississauga, Brampton and Caledon, in effect through Sunday, warning of thunderstorms capable of dropping 30 to 40 millimetres of rain per hour. Environment and Climate Change Canada reported Friday afternoon that some areas of the Mississauga–Brampton region had already taken 50 to 100 millimetres of rain that morning, with additional localized amounts over 50 millimetres possible.

DrainCom's dispatch logged 17 emergency calls between Friday morning and Saturday morning, up roughly per cent from a typical August weekend. The first neighbourhoods to report backups were Mississauga, Toronto and Richmond Hill.

"Rain like this doesn't test your house evenly. It tests the weakest connection," said [Spokesperson Name], [Title] at DrainCom Inc. "In the older pockets we're seeing sewage push back through the floor drain. In the newer subdivisions it's groundwater lifting through the slab because the clay outside can't take another drop."

Four things to do before the water goes down

DrainCom is issuing the following guidance, which applies whether or not a homeowner calls a contractor:

Treat the water as live. Floodwater in a basement may be carrying electrical current and may contain bacteria or sewage. Shut off power to the basement only if it can be done from a dry position. If there is any doubt, wait for a professional.
If a pipe, hose or water heater failed, shut that fixture off first. A pressurized line can release hundreds of litres an hour. Know where the main shut-off valve is before you need it.
Do not pump the basement out all at once. Draining a severely flooded basement too quickly can damage foundation walls, because the water pressure outside the wall drops far more slowly than the water level inside.
Photograph everything before you move it. Insurers want a record. Get photos, documents, fabrics and electronics up off the floor, then call your insurance company to confirm what your policy covers. Many standard policies exclude sewer backup unless a rider was added.
A warning about the week after a storm

The company is also flagging a pattern that follows every major rainfall event in the GTA: door-to-door solicitation by out-of-area contractors offering same-day waterproofing at cash prices.

"Somebody standing on your porch the morning after a flood, telling you they can dig your foundation this afternoon, is not doing you a favour," said Serge Robak. "Ask for the licence. Ask for the permit. Ask who's coming back in five years if it leaks again. In Ontario, work a homeowner or an unlicensed crew does isn't eligible for municipal flood protection subsidies either, so a cash deal can cost more than it saves."

The City of Toronto requires eligible flood prevention work to be completed by a licensed contractor in order to qualify for its Basement Flooding Protection Subsidy Program, which increased its maximum to $6,650 per property on May 1, 2026. Peel Region, Halton Region and the cities of Mississauga, Brampton, Burlington and Oakville operate separate rebate programs with their own rules.

Why Peel keeps flooding

Mississauga sits largely on heavy clay, which holds water against foundation walls rather than absorbing it. Older parts of Toronto still run combined sewers that carry stormwater and sanitary waste in one pipe, and in homes built through the mid-1900s the foundation weeping tile is often tied directly into the sanitary line.

The region's recent history is the argument. On July 16, 2024, Mississauga recorded upwards of 106 millimetres of rain between 8 a.m. and noon, an event the city's conservation authorities rated as slightly more intense than a one-in-100-year storm. Two record storms that summer, in July and August, delivered roughly 280 millimetres of rain to the city. Severe rainfall in 2024 flooded more than 1,000 homes in Toronto alone.

DrainCom is running emergency dispatch through the weekend and offering free basement inspections and estimates across Toronto and the GTA.

About DrainCom Inc.

Founded more than two decades ago and based in Mississauga, DrainCom Inc. is a licensed and insured basement waterproofing, foundation repair and drain service company serving Toronto and the Greater Toronto Area. The company reports having waterproofed or repaired more than 20,000 homes, covering over 300,000 linear feet of foundation wall, and holds a 9.9 out of 10 rating from more than 800 reviewers on HomeStars. Services include interior and exterior basement waterproofing, flooded basement cleanup, foundation crack repair, French drain installation, drain and sewer camera inspection, high-pressure water jetting, trenchless pipe replacement, sump pump and backwater valve installation, basement underpinning and emergency plumbing. Most work carries a 25-year transferable warranty. More information: draincom.ca

Website: draincom.ca