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Relocating Guildford sewage treatment works

We’re proposing we relocate our existing Guildford Sewage Treatment Works (STW) to an area north-east of Slyfield Industrial Estate, Guildford. 

This will give Guildford Borough Council the space they need to complete the development work allocated in their Local Plan, providing much-needed housing for the local area.

Our online pre-application public consultation is open until Friday 16th July 2021. You can give your feedback by completing our form.

How we treat wastewater

Every day, we collect billions of litres of wastewater from 15 million customers like you and transport it to our sewage treatment works for cleaning. Learn more about how this process works.

Why we’re moving Guildford STW

Guildford STW is currently located on part of the land allocated for the council’s Slyfield Area Regeneration Project (SARP), which will include the new Weyside Urban Village. We’ve agreed to relocate our STW so that Guildford Borough Council can bring this plan to life.

Their mixed-use regeneration project will provide thousands of new homes, new community facilities and 6,500m² of commercial space to improve the local area.


A map showing the proposed location of the new Guildford Sewage Treatment Works. 

We’re planning to move our STW to an area that can’t be used for housing because of its previous use as a landfill site. 

Guildford Borough Council is funding the relocation project, and we’re working closely with them to ensure a smooth overlap on both our projects.

Key benefits of our new treatment works

  • The move will enable Guildford Borough Council to build 1,500 new homes. This will help the council meet local housing needs and form part of the new Weyside Urban Village.
  • The new STW will make use of a former landfill site at the northern edge of the Slyfield Industrial Estate, which can’t be used for housing development.
  • The new STW will future-proof our wastewater treatment capacity so we can continue delivering your essential service as Guildford’s population grows.

How we’ll relocate the site

Our new STW needs to be built, connected to the network and fully operational before we can shut down the old site.

This means we’ll construct the new site while the current site continues to treat your wastewater. Once we’ve connected and tested the new site carefully, we’ll transfer wastewater between the two sites and take the current site offline.

There are three key elements to our relocation project:

  • A new STW located to the north-east of the existing Slyfield Industrial Estate in Guildford, which will replace the existing Guildford STW
  • A new effluent and stormwater outfall pipe to the River Wey, just north of the new STW
  • A new gravity transfer tunnel running from the existing inlet pumping station to the new STW, to transfer incoming wastewater from existing sewers to the new STW

Construction of the new STW should take approximately three years, followed by around 12 months of commissioning when we’ll test the new site’s treatment processes thoroughly before use. If our planning application is approved, we expect to start our work in summer 2022 and complete it by autumn 2026.

A satellite image of Guildford with the existing treatment works, new treatment works, transfer tunnel and new outfall marked

Our new STW in detail

Learn more details about how we'll build our new Guildford STW.

Learn more

The planning permission process

We’re expecting to submit a planning application to Surrey County Council as the waste planning authority in late 2021

We’re currently looking for the right design and build contractor to create our new STW.

After we’ve appointed one later this year, we’ll use their comments, as well as yours from this consultation, to create a final design for our planning application.

Timeline of the application

  1. Our public consultation will take place in May/June/July 2021
  2. We’ll consider your feedback in September/October 2021
  3. We’ll submit our planning application by the end of 2021
  4. Surrey County Council will carry out a public consultation on the application
  5. If approved, construction will start in summer/autumn 2022

Minimising our impact

Learn how we’ll do everything we can to minimise our impact on you.


Learn more

Give your feedback

If you have any questions or comments on our plans, please complete the feedback form by Friday 16 July.

Complete our feedback form
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