The plants will generate energy from biogas as bi-products of the sludge treatment process and also produce fertilisers for recycling to land.
Galliford Try has completed similar anaerobic digestion plants for Anglian Water at King's Lynn in Norfolk and Great Billing in Northamptonshire.
Galliford Try chief executive Greg Fitzgerald said: "We are delighted to secure this additional business from an existing framework client. It builds on our track record in delivering both clean and waste water infrastructure projects as a leading infrastructure contractor to thewater industry."
Got a story? Email news@theconstructionindex.co.uk