Protecting communities from sewer flooding is complicated and needs the cooperation of all the organisations involved in managing roads and transport, planning and the development of new buildings.

This includes local authorities and we work closely with them on flooding issues, new development, and their long-term strategies.

Additional sewage from new developments can be a major cause of sewer flooding, so it is very important that we talk to planning authorities to make sure that we can add extra capacity to the sewer system, before new properties are connected.

Local authorities can also help prevent sewer flooding by reducing the amount of green spaces that are paved over to provide off-road parking, as this stops rainwater draining naturally and adds to the amount of water that enters our sewers.

We also help local authorities to prepare Surface Water Management Plans, which identify areas at risk of flooding following heavy rainfall and provide strategies for managing this risk.

In London, we are working with boroughs to carry out trials of sustainable drainage techniques, which can reduce the impact of rainfall on sewers.

These trials will help us to understand the costs and benefits of these measures and how well they help to reduce sewer flooding, as well as how they improve the service we provide to our customers.