Harding will be tasked with growing the £31m turnover business after a successful bidding run for AMP7 frameworks.
Over seven years at Kier, Harding rose through the ranks of the utility contracting business to become an operations director before leaving last June.
Matthew Bridges, owner and managing director of the family business, said: “The role of operations director is a key strategic appointment designed to strengthen assurance across all our operations for AMP7 and the future, ensuring we continue to add value and provide excellent customer and end user experience.
“With over 25 years in the water sector successfully delivering complex infra and non-infra programmes, Toby brings to Bridges extensive knowledge and experience of regulatory, client and delivery frameworks.
“His leadership and collaborative approach will bring surety to Bridges operational activities, shaping and aligning our services and teams to achieve our strategic ambitions.”