Wiltshire Council Launches £22m Tender for M4 Junction 17 Upgrade with Focus on Infrastructure and Community Benefits

Wiltshire Council is seeking to appoint a contractor for a major upgrade to Junction 17 of the M4, in a project aimed not only at improving traffic flow and road safety, but also delivering long-term economic and community benefits to the region.

The contract is estimated to be worth up to £22 million, with construction scheduled to run from April 2026 to September 2028.

The improvement works will include:

• Installation of traffic signals at all roundabout approaches to manage congestion more efficiently

• Widening of carriageways throughout the junction to improve capacity and reduce delays

• The addition of a third traffic lane across the motorway bridges

• Widening of the circulatory carriageway to enhance vehicle flow, particularly at peak times

The scheme will be delivered in two key phases:

• Phase One – Early Contractor Involvement (Spring to Autumn 2026): During this stage, the appointed contractor will work collaboratively with the council and stakeholders to finalise the design, refine delivery methods, and assess risks to minimise disruption.

• Phase Two – Construction (2027 onwards): The main works will be undertaken, with efforts made to phase construction to reduce the impact on local traffic and surrounding communities.

  
  

Driving Local Benefits

Beyond the transport improvements, Wiltshire Council is committed to ensuring that the project delivers wider social value:

• Job creation and skills development: The council expects bidders to outline how they will support local employment, apprenticeships, and skills training throughout the contract period.

• Support for local businesses: Contractors will be encouraged to source materials and services locally where possible, supporting supply chain growth across Wiltshire.

• Sustainability commitments: Environmental management will be a key focus, with strategies expected to minimise carbon emissions, reduce waste, and protect biodiversity during the construction process.

• Improved connectivity for communities: The upgraded junction will improve access between Chippenham, Malmesbury, and the surrounding areas, supporting economic growth, safer journeys, and reduced travel times for residents and businesses.

  
  

Wiltshire Council also aims to maintain regular communication with residents and road users, offering updates and engagement opportunities throughout the life of the project to ensure transparency and community input.

Tender Timeline

• Enquiries Deadline: 5 December 2025

• Tender Submission Deadline: 19 December 2025

• Contract Award Notification: 23 March 2026

• Contract Start Date: 6 April 2026

• Estimated Completion: 29 September 2028