Galliford Try, in partnership with Severn Trent, is in the last stages of the Stroud Sewer Strategy project.

This critical project, in construction for the past two years, aims to control and significantly reduce flood risk within the Stroud Five Valleys area, and and includes installing four miles of new enlarged pipes, as well as separating surface water from the waste network.

The project has reached a pivotal point with the completion of the new trunk sewer and the main Combined Sewer Outfall (CSO) shaft tank, as well as the installation of the lid on the CSO shaft tank.

The 25m deep by 25m wide concrete-lined tank has a capacity of 7,400m3 – the equivalent of three Olympic-sized swimming pools or over 24,500 bathtubs of water.


The tank will drastically improve water storage capacity by 1,300% during heavy rainfall, helping to reduce sewer flooding and spills into rivers and watercourses. It will have cutting-edge smart controls that can hold storm water back during severe weather events and return it to Severn Trent’s treatment works when rainfall has subsided.

As part of the project, extensive ecology work was also carried out to ensure the conservation of wildlife in the area, including the protection of badger setts, newt population, and arboricultural surveys to create root protection zones.

Mark Shadrick, Managing Director of Galliford Try’s Environment business, commented: "This project shows our commitment to building robust and sustainable infrastructure that makes a real difference to the lives of local people. The success of the Stroud Sewer Strategy is a testament to the dedication and expertise of our team and partners. We look forward to seeing the long-term benefits this project will bring to the Stroud area."

The £25 million Stroud scheme will also include the removal of a large sewer pipe that runs through the canal in the town, plus improvements at the Stanley Downton Sewage Treatment works.