During a serious drain blockage, avoid running more water, flushing toilets, mixing or pouring drain chemicals, and lifting covers or reaching into drains. These actions can make the backup worse, create new risks or delay the problem being cleared safely.
When a drain is badly blocked, it is natural to want to fix it quickly. Some common reactions can do more harm than good, especially when wastewater is already close to coming back into the property.
Do Not Keep Running Water
Flushing a toilet again to see if it clears, or running taps to push the blockage through, can send more water into a drain that has nowhere to go. This may cause wastewater to rise through the lowest fixture, often a toilet, shower tray or floor drain.
Remember appliances too. A washing machine or dishwasher that empties during a blockage can add a lot of water at once. It may help to let others in the home know not to use water until the drain is cleared.
Do Not Rely on Drain Chemicals
Chemical drain cleaners are not designed to clear a serious blockage in a main drain, and they may not reach it at all. If they do not work, you may be left with standing water that contains harsh chemicals, which can be harmful to skin and eyes.
Never mix different drain products, or use bleach alongside drain cleaner, as some combinations can give off harmful fumes. If you have already used a product, tell whoever comes to clear the drain.
Do Not Open Up the Drain Yourself
Drain covers and inspection chambers can be heavy and awkward to lift, and the chambers underneath may be deep and contain sewage. Do not climb into or lean into a chamber, and keep children and pets away from any open drain.
Avoid hiring powerful equipment to tackle a blockage without the right knowledge. Using it wrongly can damage pipes or cause injury. Repeated plunging of a toilet or drain while water is rising can also splash wastewater around and may not shift a blockage further down the drain.
What to Do Instead
Stop using water in the property as far as you can. If you know which fixtures drain into the blocked section, put a note on them so no one uses them by mistake. Keep away from any wastewater, wash your hands after any contact and keep the area ventilated. If neighbours are affected too, the problem may be on a shared or public sewer and may need reporting to your sewerage company.
Note which fixtures are affected and when it started, and take photographs if water has escaped. Our emergency drain clearance page explains how urgent blockages are assessed and what is involved in clearing them.
If you are dealing with a serious drain blockage in Poole, a plumber can talk through the situation and explain the safest next step.