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Upgrading our network

We invested £7 billion from 2020 to 2025. This has delivered improvements for customers and communities, including:

  • Reducing leakage
  • Creating jobs
  • Helping the environment

Ensuring life's essential service for generations to come

Today we deliver 900 billion litres of water and treat 1.8 trillion litres of wastewater every year. We maintain a complex network of 87,000 miles of water and sewer pipes and 354 treatment works. But our population is rising and climate change means weather is unpredictable. We must invest to continue delivering world-class water for generations to come.  

view of wroughton reservoir

Investing in our environment

In 2025, we connected the 7km Lee Tunnel to London’s largest ever super sewer – the Thames Tideway. The tunnels, plus improvements to our London treatment works, will have a huge impact. They will massively cut storm overflows into the tidal Thames by as much as 95%.

They’ll improve the water quality of our rivers and encourage wildlife to thrive. It’s a project many years in the making. A feat of engineering our talented teams and partners should all be incredibly proud of.

Thames Water engineer in orange hi-vis

Investing in our region

  • Over £7 billion across our network since 2020
  • 150,000 ageing water pipes replaced
  • Cleared 350,000 sewer blockages
  • Over one million smart meters installed
  • 17 acres of new wetlands so wildlife can thrive
  • 1/4 of our energy self-generated with waste power
  • Over £260 million in financial support for those who need it most
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