Coppermills advanced water treatment works
We’re upgrading Coppermills Water Treatment Works (WTW) in Walthamstow to modernise the site and improve its performance.
Much of the existing infrastructure at Coppermills Water Treatment works dates back several decades. While it has served the community well, parts of the site now needs updating.
These essential works will help to make sure we continue to supply high-quality drinking water, while supporting a more resilient water supply and protecting the environment.
What the project will involve
As part of the project, we'll be:
- Replacing the 1960s pumping station
- Building new pipes, chambers, and control structures above and below ground
- Upgrading the power supply system
- Moving parts of our internal fence to make extra space
This project forms part of our biggest upgrade in 150 years. It will help us meet growing demand, improve resilience, and support environmental commitments, whilst continuing to provide safe, high-quality drinking water.
When and where we'll be working
Main construction work is scheduled to commence in Autumn 2026 and is expected to take 5 years to complete. All work during this time will be completed within our site boundaries.
Coppermills Water Treatment Works is adjacent to a protected wetland in Lee Valley. We will carry out our works in a way that protects the environmentally sensitive features of this important habitat.
How you'll be affected
At this stage, you’re unlikely to notice much change as we prepare for the main construction works.
As the project progresses, there may be times when temporary measures, such as parking restrictions, are needed to support safe working. Where this is required, we will provide advance notice and engage directly with local residents and businesses to minimise disruption as much as possible.
We are committed to keeping any impact to a minimum. Your water supply will not be impacted during these works. We will keep you informed throughout the project by letter and updating this web page.