Major disruption is expected this weekend as M3 is closed in both directions for crucial work to junction 9 scheme

National Highways is closing the motorway between junction 8 and junction 9 in both directions from 9pm on Friday, January 30 to 6am on Monday, February 2 so steel beams for the new roundabout at Junction 9 can be safely installed on the north side of the junction. A diversion route will be in place along the A34 and the A303.

This work will then be repeated over another full weekend closure two weeks later – from February 13 until February 16 – to install the 40 metre, 100-tonne beams at the south side of the junction.

Tom Beasley, National Highways senior project manager, said: “This junction is a key interchange for economic growth, connecting the ports of Southampton and Portsmouth to the rest of the country, and allowing millions of tonnes of freight to be shipped.

“It also provides a vital route for those travelling to the south coast, whether that’s for business or leisure.

“Changing the layout of the roundabout is fundamental to improving those links, and installing the first bridge beams this weekend marks a major milestone for the scheme.

“To do that safely, we need to close this stretch of the motorway and advise anyone travelling through the area to plan their journeys carefully and allow extra time where possible.”

The upgrade is needed to support the building of 2,000 new homes in Winchester and will improve reliability for drivers – with peak time journeys set to be almost 30 per cent faster through the junction to the A272, National Highways has said. It also added that between the M3 and A34, drivers will save more than 20 per cent of their overall journey time during peak hours with the M3/A34 route also popular for drivers from the Portsmouth area who are travelling north.

Once the beams are in place, construction on the new roundabout will continue over the coming months, before fully opening to traffic in summer 2028.

National Highways has said that reconfiguring the roundabout in this way will allow the M3 to be widened, enabling dedicated A34 links to be established and making it easier for freight travelling from the port to the Midlands and beyond.

The project will also provide a host of environmental benefits, including more than 22 acres of chalk grassland, as well as new routes for walkers, cyclists and horse riders.