If you think there is a blockage or if your property has been flooded by our public sewer, please call us on 0845 9200 800 (Textphone: 0845 7200 899) and one of our team will be here to help, 24 hours a day.

Climate change, population growth, and the paving over of green spaces that provide natural drainage are putting increasing pressure on our sewerage network.

This is often made worse by people putting unsuitable products down the sink or toilet, increasing risk of sewer flooding.

Many areas have separate sewers to take foul waste and rainwater, but in much of London and some other urban areas, the sewer system is combined, meaning that foul sewage from kitchens and toilets mixes with rainfall.

This means that, during a heavy storm, the flow in the sewer is much greater and can reach maximum capacity.

Our sewers are designed to cope with the vast majority of storms but occasionally rainfall can be so heavy that it overwhelms the system.

When this happens, sewage can overflow from manholes and gullies and flood land, rivers and gardens. In the worst cases, sewage can even flood homes.

Sewer flooding is unacceptable and we treat all cases with the highest priority.

We prioritise our investment for potential flood alleviation schemes depending on the severity and frequency of flooding, and so it important that you report all flooding so we can keep our records up-to-date.

• Find out more about our sewer flooding alleviation projects

Sewer flooding questionnaire

If you have been flooded by our public sewer but have not let us know us, please download and complete our sewer flooding questionnaire and return to us at the address on the form.

• Sewer flooding questionnaire (0.05Mb)

Cleaning up

If our public sewer has caused flooding, we will offer to carry out a clean-up of the affected area(s), at no cost to you.

We aim to do this on the same day, but this may not always be possible if a large area is affected, or if flood waters have not yet drained away.

In these cases we will aim to get to your property within 48 hours of us finding out about the flood (our response times may vary during periods of exceptional weather). Our clean-up service may include:

• Litter picking
• Washing down affected areas
• Pumping out basements
• Disinfection

You may be able to get a more comprehensive clean-up service through your household insurance cover, so you may like to arrange this with your household insurance company.

Contacting your insurers

It is important that you contact your household insurance provider straightaway and tell them about any damage caused by the flooding. If you do not do this, it may affect any insurance claims you need to make.

If you are not insured and are having financial problems, we may be able to help you.

We may not be liable for damage caused by sewer flooding when it occurs for reasons beyond our control.

We have no control over what is put into sewers or the amounts of rain that falls in our region, and the law recognises we should not be responsible for any flooding damage caused as a result.

We are only responsible for damages if flooding is a result of our negligence.