Try the closest valve first
If the leak is at a toilet, sink or dishwasher, look for the small oval or round stop on the supply line under or behind the fixture. Turn it clockwise until it stops. Quarter-turn stops close with a flick of the lever so it sits across the pipe. If the drip stops, leave the rest of the house running and call to book the repair at a normal pace.
Multi-turn stops under older sinks are often seized. Do not lean on them with pliers. A stem that snaps off leaves you with a full-pressure leak and no way to stop it except the main.
Finding the main in a North York house
- Postwar bungalows and side-splits around Bathurst Manor, Wilson Heights and Parkwoods: usually on the front basement wall, low, close to where the service pipe comes through the foundation, often behind a laundry tub or inside a storage room.
- Older homes near Hogg's Hollow and Lansing: the service may enter under the front porch, with the valve in a cold cellar.
- Newer infill and rebuilt houses in Willowdale: often in a mechanical room next to the water meter, with a lever valve on copper or PEX.
- Condos and towns: the suite valve is usually in a closet near the heater or behind an access panel in the laundry nook. Building management controls the riser.
The valve sits next to the water meter on the house side. Follow the pipe that comes in from the street side of the house.
If the leak is at a toilet, sink or dishwasher, look for the small oval or round stop on the supply line under or behind the fixture.
From the counter
Closing an old gate valve
- Turn the round handle clockwise slowly, by hand.
- If it stops after a few turns but water still runs, do not force it. Old gates wear and never seal fully; the plumber will replace it.
- If a drip starts at the packing nut under the handle, snug the nut an eighth of a turn with a wrench.
- Run a basement tap, the lowest one you have, so the lines bleed down.
When the main will not budge
The city curb stop near the property line can shut the whole supply, but it needs a long key and the box is often buried or full of silt. Call Toronto Water at 311 if you cannot close your own main, and call us at the same time so we can replace the inside valve once it is isolated.
Do not forget the heater
If the leak is on the water heater, close the small valve on the heater cold line as well. For an electric tank, switch the breaker off so the elements are not left heating an empty tank. For a gas tank, turn the control to pilot.