Drain blockages - guidance to householders

Blocked household drains are inconvenient and can be a potential health hazard. Drain blockages are preventable.

Common causes

• pouring cooking fat, oils and grease down drains - these can solidify into the waste system and are difficult to remove
• detergent scaling, particularly in hard water areas
• flushing paper and cloth products such as disposable nappies, sanitary towels, cotton wool buds and newspapers down toilets - they can form a solid mass and eventually stop the flow of water.
• pouring cement and plaster down drains - these can set rock-hard in the drain
• pouring waste oil from motor vehicles into drains - it is illegal to do this
• collapsed or damaged pipes.

How can I get drains unblocked?

Find a specialist contractor from the telephone directory. Be sure to ask about hourly rates and call-out charges as these can be expensive, particularly at weekends.

Alternatively, contact Thames Water on 0800 316 9800 . It operates a 24-hour, 365 day a year, drain clearance service (chargeable).

What if drains keep blocking?

This may suggest that the pipes are faulty. Tree root penetration and subsidence are common causes of broken pipes.

If you are a property owner, you may want to have the drains surveyed using close circuit television equipment. The council can approve this service for a charge. You may find that the cost of a drain repair to your house is covered by your insurance.

If you rent your home, your landlord is generally responsible and should arrange for remedial works to be carried out.

If you are a council tenant and your outside drain is blocked, contact the housing on 020 8726 6100.

Road gullies on private highways

Report a blocked gully or drain problems online using the Love Clean Streets app or website.

We aim to resolve reported issues within 10 working days. In some instances, it may take longer to resolve; for example if the blockage is in relation to secondary problems.

Further help and advice

If you want to report a drain problem or require further advice, email the private sector housing team, details below.