Water resources

Water is vital to our quality of life – too much of it and we can experience flooding, too little of it and we can be in drought. In London we use more than 2.6 billion litres of the stuff every day – that’s enough water to fill the Royal Albert Hall 26 times every day.

But we live in the driest part of the country, where there are also the most people. We are therefore working with the water companies that supply our water, treat our sewage and manage our drainage and other partners to ensure that we use the water we have wisely, that we plan for future challenges and that our water bills are affordable.

We rely on our rivers for most of our water

We get most of London’s water from the rivers Thames and Lee. The remainder comes from groundwater that lies underneath London.

Water pressures

We are using more water than we should – meeting our current demands is starting to have a negative impact on the environment. However, our demand for water is increasing as our population grows. And climate change is likely to reduce how much water is available when we need it most – in the summer. Thames Water estimate that the gap between supply and demand for water will grow to over half a billion litres a day if we don’t act.

Working together to manage London’s water resources

We are therefore working with the water companies, the Environment Agency and other partners to achieve the effective management of London’s existing and future water resources to meet the needs of the growing population while protecting the natural environment. This includes both making sure we use the water we have wisely, by improving water efficiency and reducing leakage, as well as finding new sustainable water sources. The Mayor has convened a Water Advisory Group to advise him on the water challenges and opportunities of London’s growth.

Putting rainwater to good use

Almost a billion tonnes of rain falls on London every year. Using rainwater rather than letting it go down the drain can help to relieve pressures on the drainage system – reducing flood risk and the demand for treated water. We want people to see rainwater as a valuable resource and not something to be mixed with sewage and got rid of. We are working with Thames Water, the Environment Agency and the London Boroughs on the London Sustainable Drainage Action Plan to keep rainwater out of the drains and sewers by keeping it in new green spaces.