Major UK motorway to finally get new £363m upgrade in 2026

Drivers in Gloucestershire are set to benefit from full access to the M5 at Junction 10 for the first time, as work on the long-awaited upgrade is scheduled to start early next year. Currently, the junction only allows access northbound, but the £363m project will allow motorists to join and exit the motorway in both directions, tackling congestion in west Cheltenham and improving connections across the region.

The scheme, approved by Transport Secretary Heidi Alexander in June, is a cornerstone of development plans for north-west Cheltenham, including the ongoing Golden Valley housing and jobs scheme. Major construction is expected to continue through 2028, with preparatory work already under way.

The upgrade will see four new slip roads replace the existing two, and two single-span overbridges constructed to replace the ageing Piffs Elm Interchange Bridge.

A new elongated roundabout will connect the slip roads and the realigned A4019, which will have a 50mph speed limit across the junction. Motorway slip roads will retain the national speed limit.

Sustainable transport is also a priority. Pedestrians, cyclists, and horse riders will benefit from dedicated routes through and around the junction, including a new underpass east of the M5.

The scheme will extend the Leigh Brook culvert, retain the River Chelt culvert, and include landscaping and planting along the riverbanks to enhance biodiversity.

Highway drainage will feed into new attenuation basins, while flood storage measures will offset the construction impact.

However, the project has faced scrutiny over rising costs. Originally estimated at £249m, the budget has ballooned to £363m, leaving a £110m funding gap.

Gloucestershire councils have pledged £40m, with the remaining £70m still awaiting government approval. Cost increases have been attributed to "extended timelines, inflationary pressures, and additional requirements" linked to the Nationally Significant Infrastructure Project approval process.

Gloucestershire County Council cabinet member Julian Tooke said: "This is a crucial piece of the funding jigsaw. With strong regional support, we are a step closer to delivering the infrastructure needed to support housing, employment, and investment."

Tewkesbury Borough Council leader Richard Stanley added: "Full access to the M5 in both directions will make it easier for everyone to travel, work, and thrive. It will shorten journey times, tackle congestion, and support sustainable transport."