Costain has appointed Peter Mumford as managing director for its natural resources division.

Mumford will join Costain’s Executive Board and start on 2 January 2026.

He replaces Sam White who left in October to become managing director of Mitie’s Technical Services division.

Mumford joins from Balfour Beatty where he was managing director of its regional civils business in the UK.

Prior to that he spent five years at National Highways leading the delivery of the government’s £27bn road investment strategy.

Alex Vaughan, chief executive at Costain, said: “Our natural resources division continues to grow from strength-to-strength and is delivering predictable, best-in-class infrastructure services to our customers in the nationally critical markets of water, energy and defence.

“I’m looking forward to Peter bringing his broad and deep leadership experience so that we can continue to deliver infrastructure for a more prosperous, resilient and decarbonised future.”

Mumford added: “Costain’s reputation and heritage is second to none. I’m excited to be joining the company at this time and adding to its excellent track record in delivering complex and essential infrastructure in the water, energy and defence markets.

“I am looking forward to accelerating Costain’s growth through our strategy of developing long-term strategic partnerships with tier one customers, broadening our service offering, and remaining an attractive and trusted contractor to our supply chain partners.”