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Self-laying new mains and services

Pre-planning enquiries

We can provide guidance on the layout or design of your project. This service is for 10 or more properties only.

View pre-planning process

About self-laying mains

You can choose to use a self-lay provider rather than Thames Water to lay mains and service connections.

View self-lay overview

Self-lay application process

It's easy to apply online once you've got all your supporting documents ready. Before you start, find out everything you need to know.

How to apply for self lay

Through bore hydrants

As of Monday 1 April 2024, we'll no longer allow squat type hydrants to be installed on our water network. We'll only accept through bore hydrants (TBH). 

Testing shows that through bore hydrants (TBH) provide a higher flow of water out of a fire hydrant, in most cases. This is why we and other water companies have opted to use them. 

We installed a TBH at Caversham fire station in 2016, which gave an extra 8% flow. TBH suppliers estimate up to 20% but any extra water for fire crews is clearly beneficial.

TBHs make it easier to access our mains for Shara and general camera surveys. This helps us understand the condition of our branch pipes offline. TBHs also have a logger point which ensures any loggers connected to it don’t affect the operation of the hydrant.

For our customers’ benefit, we can exchange a TBH without having to isolate the water main. This means the water supply won't be interrupted. 

If you have any concerns, please contact ranj.sahota@thameswater.co.uk by 15 March 2024.

Design and construction specifications

Thames Water SLP policies

Forms

Additional technical documents