Investor Oaktree Capital Management is buying the water and wastewater engineering group, which ran up losses of £4.6m in last published accounts on revenue of around £185m.

The sale is expected to be finalised before the end of the year.

Stantec announced a strategic review of construction services last April to deliver the best prospects for employees, clients, and shareholders.

Blair Lavoie, president of MWH Constructors and chief of global operations, said: “This is a positive step in the evolution of our company, and we look forward to having a partner like Oaktree with strong financial resources and a desire to invest in our future as we continue to be the leading global project delivery company in the water sector.

“In the US, we will stay with our great brands of Slayden and MWH Constructors, and in the UK, we will return to MWH Treatment.”

MWH Constructors provides design, start-to-finish preconstruction, construction, construction management, and start-up and commissioning services, primarily for the water and wastewater markets in the United States and the United Kingdom.

In the UK, it has worked with the Anglian, Southern Water, Thames and Severn Trent and Scottish Water and employs over 500 staff.

Stantec acquired MWH Global and its 6,800 team members distributed around the world in 2016.

Following the sale of MWH Constructors, Stantec maintains a significant presence in the UK with more than 1,700 team members across the UK, including 1,000 staff who joined Stantec from the MWH UK-based consultancy business.