Basement Floor Drain Backing Up in North York

GTA Plumber Match · Updated October 2026

Water coming up through the basement floor drain is one of the worst plumbing calls. In North York, it's often a main line problem in older homes from the 50s and 60s.

Basement laundry area with water pooled around a floor drain — Water around the floor drain next to the laundry. Stop running water upstairs.

Stop the water going in

Everything in the house drains to the same line. Stop running taps, the dishwasher and the laundry, and don't flush toilets until it's cleared.

Common causes in North York homes

Roots from mature trees in Lawrence Manor, Armour Heights and Bathurst Manor getting into older clay or cast iron lines.
Grease building up in the kitchen line where it joins the main.
Heavy rain overloading the City sewer, especially in neighbourhoods near the Don valley.

Is it one drain or all of them?

If only one sink is slow, the clog is local. If the floor drain backs up when you run the washer or flush upstairs, the main line is blocked.

Sewer camera screen showing roots inside a drain pipe — A camera inspection shows what's actually blocking the line.

Fixing it properly

A plumber can clear the line, then run a camera to see why it blocked. If it happens again and again, ask about a backwater valve. The City of Toronto's basement flooding subsidy can help with the cost in North York too.

Text us a photo and your postal code. We'll connect you with a vetted, licensed, WSIB-covered plumber, usually same-day.

Basement Floor Drain Backing Up in North York

Stop the water going in

Common causes in North York homes

Is it one drain or all of them?

Fixing it properly

Need a plumber in North York?

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