Costain, the infrastructure solutions company, has been awarded work by Thames Water to upgrade strategic treatment assets across the Thames Valley region.

Photo credit Thames Water: Esher Wastewater treatment works 

The award will see Costain complete around £150 million of essential upgrades to wastewater treatment assets across 15 sites as part of Thames Water’s Wastewater Asset Assurance Programme (WAAP).

Thames Water is undertaking its biggest ever upgrade of sewers and sewage treatment works in 150 years, with improvements planned at more than 250 sites across the region. Costain’s upgrade works will include modernising operations at inlet stations, improving the resilience of storm tanks and other repairs, modifications and upgrades to wastewater systems, and are expected to be completed during AMP8, which covers the period of 2025 - 2030.

Costain’s upgrades will see it split the works into two regions, East and West, appointing a regional senior project manager for each region. The wastewater treatment sites in the Eastern section will include Barkway, Brentwood, Long Reach, Little Hallingbury, North Weald and Standon. The Western section will include Aldershot, Burghfield, Esher, Horley, Lightwater, Marlborough, Northleach, Waddesdon and Windsor.

Costain is a long-term, trusted partner of Thames Water and was previously awarded contracts to upgrade strategic treatment assets in Markyate, Brickendon, Sandhurst and Selborne assets. Costain has also been involved in conducting clay compaction trials for The White Horse Reservoir, Thames Water’s new 150Mm3 reservoir in Oxfordshire which will provide a resilient water supply for up to 15 million people.

Matt Bateman, Water Sector Director at Costain, commented:

“We have a long-term, trusted partner relationship with Thames Water and this award is built on our excellent track record of identifying construction efficiencies and delivering best-in-class solutions. We’ll work closely with Thames Water and our supply chain partners to deliver these essential infrastructure upgrades, that will build resilience into the region’s critical wastewater system, efficiently and safely.”

Tim Horton, Capital Delivery Director at Thames Water, added:

“We are delivering the largest programme of investment in our wastewater network in more than 150 years, helping to improve resilience across our region and support a growing population.

“Costain has a strong track record of safely delivering complex infrastructure projects and will play an important role in upgrading key treatment assets across these 15 sites. Together, we will modernise critical wastewater infrastructure, improve operational performance and help ensure we continue to provide a more reliable service for our customers and the environment.”