Hampshire County Council is looking for a contractor to do work on junction 10 of the M27, the turning for the A32 and Wickham. Currently drivers can only join the eastbound carriageway and leave the westbound side, but it will be turned into an ‘all-way’ junction.
This will be the first stage in getting 6,000 homes built at Welborne - a development more than a decade in the making.
Councillor Rob Humby, deputy leader of Hampshire County Council and executive lead member for economy, transport and environment, is expected to put the contract out for tender this week.
'We have always supported the plans for development of a new garden village at Welborne, recognising that in addition to providing much needed homes, it will boost the local economy, provide commercial floorspace and create jobs,' he said.
'This will be the biggest transport scheme that we have ever delivered, and we do not underestimate the magnitude of the task.
'As the Highways Authority for the local road network in Hampshire, our transport planners and engineers manage the development and delivery of large transport projects on our own network all the time.
'However, managing such a technically complicated and demanding project on the national highways network is a good deal more challenging.’
The creation of a motorway underpass and three slip roads at the site will be the largest transport scheme that the county council has ever managed, Cllr Humby added.
The M27 work is critical to the Welborne project, as it will handle extra traffic generated by the new town.
Leader of Fareham Borough Council, Cllr Sean Woodward, says he is excited to see progress made.
He said: 'I put the idea of Welborne forward more than 15 years ago, so it has been a long time in the making.
'Projects on a scale such as this take time, but the critical stages - securing planning permission and starting the development of junction 10 - are completed.
'It's a good feeling, seeing everything come together. There are those who say Fareham is full, but the bottom line is we have to build these houses and Welborne is a great place to do it.'