‘No dig’ technology increases lifespan of Yorkshire’s sewers

The lifespan of Yorkshire Water’s underground sewers could increase by up to 50 years after the company has trialled a “no dig” gravity fed lining system in what it describes as a “world first”.

Use of the technology is also expected to save the firm around £1.25 million over five years by renewing large sections of its underground gravity fed sewer infrastructure without having to replace it.

It consists of a carbon fibre spray lining application that rapidly sets to create a “pipe within a pipe”, creating a 2mm thick extra layer of structural integrity that protects against groundwater infiltration.

The technology can also be applied without having to dig up the road surface, which will result in less road closures and traffic disruptions, the company said.

Mark Gregory, project manager at Yorkshire Water, said: “We have previously carried out successful trials with this technology on our water mains and sewers, but this is a world first in terms of using it specifically for gravity fed sewers.

“The spray liner has proved itself to be a highly cost-effective effective and innovative way to renew ageing infrastructure. By applying this technology we will substantially reduce the risk of failure to our ageing underground assets and also improve the life span by 50 years.”

Yorkshire Water plans to use the new technology on “vulnerable” rising main sewers. It will carry out a review with the aim to examine future applications on its wastewater network and its potential to be used on the clean water network.

The technology has been developed by Axalta Coating Systems and Yorkshire Water, and applied by Schur Ltd and Peter Duffy Ltd based in Wakefield.

Yorkshire Water said it is working with the public health and safety organisation NSF-WRc to establish “industry standards” for use of the new technology.