Updated plans for notorious bottleneck at Winchester's M3/A34 Junction 9 go on display

WATCH: National Highways' virtual fly-through of what the proposed upgrade will look like.

National Highways is showcasing updated plans for an upgrade of the M3's junction 9 at Winchester.

The government-owned company is holding two public events where people can hear more details about the design changes.

What will the changes mean for drivers and local residents?

Why do National Highways believe the changes are needed?

The M3 connects south Hampshire with London, the Midlands and the North.

It is also part of a key freight route, and at peak times, 6,000 vehicles an hour go through Junction 9, regularly creating a bottleneck and significant delays.

National Highways say the new proposed layout for the junction aims to: 

  • Improve safety by reducing queuing and delays

  • Reduce congestion and improve journey times

  • Reduce the number of people affected by noise and improve air quality

  • Improve conditions for non-motorised users – a new cycle path would connect 

  • with National Cycle Network Route 23 which is severed by the current layout

  • Support economic growth – improving road capacity which will help create jobs, improve business and support the building of new homes

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What will the new layout look like?

New, free-flowing junctions will be created between the M3 and A34 in both directions, meaning traffic travelling between the routes will not have to stop at a roundabout or traffic lights as they currently do.

The current roundabout at Winnall will be reconfigured, creating better connections for local traffic.

A new slipway will also be created between the A33 and the M3 northbound.

The M3 southbound slip road will be removed and replaced further north, allowing traffic to join the A34 northbound and link to the new junction to maintain local access.

Click here for a look at the consultation brochure

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Will the changes be significant for the local area?

Yes. National Highways say the upgrade plans involve significant changes to the existing infrastructure.

New slip roads will be created, the M3 will; be widened to four lanes, and new bridges and underpasses need to be constructed.

In addition, a footbridge will be built over the River Itchen, and cyclcling and walking routes upgraded.

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What is the timescale for the work?

The work is currently in the consultation stage.

National Highways hopes to make a full planning application in the next few months, with ecological and engineering surveys taking place in Spring 2023.

The plans then be sent to the Planning Inspectorate, with a final decision announced by the Secretary of State in Spring 2024.

Work would begin in Winter 2024 with a view to completing the project in late 2027.

Details of how the traffic-flow would be managed during the works have yet to be announced.

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The A34/M3 Junction at Winnall is a notorious bottleneck

The new proposed layout for the junction aims to create safer journeys, reduce congestion at the junction making the journey times more reliable and a better environment for walkers.

The scheme is currently at the design stage, with the aim to apply for planning consent later this year.

National Highways says it has altered plans after an initial public consultation, making changes to better protect the local environment.

A spokesman said: "We’ve been working closely with stakeholders and local authorities to understand how our scheme can support local nature and wildlife, whilst simultaneously increasing capacity on our network and making the road safer for users."

Full details can be found on the organisation's on-line portal