The cost of a new road designed to unlock 4,000 new homes near King's Lynn and ease congestion on the A10 has risen significantly after gas main diversion costs came in far higher than first estimated.

Cabinet approved a £12.55 million increase to the West Winch Housing Access Road budget, bringing the total to £121.75 million. The increase relates to diverting two high-pressure gas mains that run through the route.

National Gas Transmission initially provided a cost estimate for the diversion work, but a revised figure provided in 2025 came in at £24.5 million — 600% higher. Cabinet heard that National Gas Transmission has since indicated this figure should be considered an upper limit rather than a firm cost.

Planning permission for the road has been secured and the project can now move forward. Work to divert the gas main is expected to start in spring 2026.

Cabinet also heard that the housebuilder Hopkins Homes is no longer involved in the associated housing development, but that planning permission is already in place meaning another developer can take on the site.

The Chair, Cllr Kay Mason Billig, said she was pleased National Gas Transmission had been cooperative in resolving the issue, and noted the scheme was being brought forward by Norfolk County Council.