We will work safely or not at all


Client requirements

The Thames Tideway Tunnel in Central London is the largest infrastructure project ever undertaken by the UK water industry, and when completed It will be 25 kilometres long!

For assured safety throughout its construction, our client requires our gas leakage engineers to survey all identified ‘at risk’ underground assets prior to works commencing, as well as during and afterwards.

As part of the HSE guidelines, it is the responsibility of any contractor involved in commissioning, planning, managing and carrying out work on or near underground services to ensure that integrity of these assets is not compromised in any way during the project.


40Seven Solution

To give our contractors Cadent complete assurance, at every stage of the project, we scoped the following:

Baseline underground utility survey

To identify all underground assets, and assess their integrity, prior to works commencing.

Ongoing monitoring

During the construction, we’re carrying out regular checks to mitigate the possibility of main failure, which could be caused by tunnel boring machines breaking ground, or deep sheet piling on, or in, the vicinity of the shafts and cofferdams.

Final construct survey

Once the works are complete in 2025, we’ll carry out a final survey to assess the settlement of the surrounding geography, and check that there has been no further impact on the assets.

Jon Steers
Operations Manager - Gas
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The results

Through quick and quality data collection, our gas engineers have provided our client with peace of mind, during every stage of this monumental project.

Safety is paramount to us as a company, and this work exemplifies our meticulous approach when it comes to upholding excellent industry safety standards.

We have dedicated asset support teams, strategically placed throughout the distribution networks, so that in the event of an emergency we can be on site within hours, ensuring that stringent standards are met time and time again.

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