Thames Water's £20 billion investment

Last updated: October 2026

We're investing £20 billion from 2025 to 2030 to improve water and wastewater services across our region.

This investment will help reduce leaks, protect rivers, maintain high drinking water quality and make our network more resilient for future generations. It is the biggest upgrade to Thames Water's network in 150 years.

Key facts

£365 million invested in maintaining and upgrading reliable water supplies, including replacing over 100km of water mains to help reduce leaks and interruptions
1.1 million smart meters planned to help customers track water use and help us find leaks faster through our smart meter installation programme
Using smart technology to identify leaks earlier and target repairs more effectively. Learn how we're using smart technology to find leaks faster
Developing major water supply projects to help secure future water supplies for future generations. View our strategic water resource solutions

How Thames Water's investment will benefit customers

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Fewer leaks and more reliable services

We're replacing ageing water mains, upgrading infrastructure and investing in new technology to help reduce leaks and keep water flowing reliably to homes and businesses.

Learn how we're reducing leaks

A sun lit river with a long grass bank and trees in the distance with a blue sky and a few white clouds

Healthier rivers and cleaner waterways

We're investing in wastewater infrastructure to help reduce pollution incidents, improve river health and support cleaner waterways across our region.

Learn about river health improvements

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Maintaining high drinking water quality

We're upgrading treatment works, water quality monitoring and sampling facilities to help maintain the high standards of drinking water our customers expect.

Learn about water quality

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A more resilient network for the future

We're investing in major infrastructure projects and upgrading our existing network to help ensure reliable water and wastewater services for future generations.

Learn about work in your area

Investment progress

Last year, we invested £7 million every day to improve water and wastewater services across our region. From replacing water mains to upgrading treatment works, here's some of the progress we've made so far.

Replaced over 100km of water mains

Installed smart leak detection technology

Upgraded water quality sampling facilities

Cleaned 1,700km of sewers

Projects shaping the future

From securing future water supplies to improving drought resilience and investing in sustainable infrastructure, these projects are helping deliver our biggest upgrade in 150 years.

White Horse Reservoir

The White Horse Reservoir is being developed to help secure future water supplies and strengthen water resilience across our region.

View White Horse Reservoir project

Teddington Direct River Abstraction (TDRA)

TDRA will help provide additional water supplies during periods of low rainfall, improving resilience during future droughts.

View TDRA project

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Clean power at Farmoor

We're developing a floating solar project at Farmoor Reservoir to help power water treatment operations and support a more sustainable future.

View Farmoor project