Problem guide
Blocked drain: what to do before calling
A slow drain, a complete blockage, and wastewater backup require different descriptions. Here is what to observe without making things worse.
Blocked drain: stop using affected fixtures
If water is rising, stop using the affected fixture. When several drains or fixtures react at once, avoid adding more water to the system: the blockage may be wider than a slow sink.
Do not mix drain cleaners or add another product after an earlier treatment. Note the name of anything already poured into the drain and tell the professional. Chemical liquid may still be present and create a risk during the visit.
Slow drain, blocked drain, or backup?
To describe a blocked drain, note:
- the fixture involved: sink, basin, shower, bath, toilet, or floor drain;
- how many fixtures are affected;
- when the flow slowed or stopped;
- gurgling, odours, or rising water;
- any recent use of a product or plunger;
- whether dirty water or wastewater is backing up.
A kitchen drain that empties slowly may require a different response from a basement where several fixtures back up. Do not try to confirm whether the blockage is local or in the main line yourself.
When is a blocked drain urgent?
Request help promptly if water is rising, several fixtures are affected, wastewater enters the home, or essential plumbing cannot be used. Keep children and pets away from potentially contaminated water.
What should you tell the plumber?
Your area, affected fixtures, how the blockage changed, and any products used are enough to prepare the first request. A photo may help if it can be taken safely; it does not replace an inspection.
See the blocked drain service page and the guide to plumbing price factors.