Sharecast - The £600m framework covers an initial 39-month period, with an extension option to 57 months, and covers works across Southern Water's geographical region including the Isle of Wight.
Activities covered under the framework include capital asset maintenance schemes, support and delivery of emerging needs including new build installations, environmental improvement programmes, asset improvements to pumping stations and process improvement works to water, wastewater and sludge process improvement works.
Chief executive Bill Hocking said: "The environment sector is a key focus of our sustainable growth strategy, which targets growth in complementary and adjacent markets and we are delighted to have been chosen again by key client Southern Water for this new framework.
"The appointment demonstrates our growing capabilities in asset optimisation as clients increasingly look to improve existing facilities and processes."