MOTORISTS are being warned to plan their commutes as 28 weeks of work to reconstruct a major roundabout in Southampton starts today.

Millbrook Roundabout will be partially closed in four different phases, each lasting from six to eight weeks each, until April next year, with long delays expected at all hours of the day.

It is part of an £8.3 million improvement scheme, which will involve laying a new road surface, installing updated traffic signals, and implementing a dedicated two-way cycle route.

VIDEO: Drivers face long diversion for Millbrook Roundabout works - so we took a drive

And it comes the day after the city was embroiled in traffic chaos as the M27 was shut for deconstruction work to start on Romsey Road bridge, resulting in diversions through the city.

Starting today, the first phase of work will close the Redbridge Road slip-road to the roundabout, as well as the junction to Wimpson Lane and the exit from the roundabout on to Tebourba Way (northbound). This phase is expected to take six weeks.

The council says the impact of the closure is “likely to be significant” with there being congestion and delays “particularly at peak times”.A spokesperson said: “We are advising motorists to plan their journeys, allowing extra time and to follow the advised diversion routes.”

Following this, the second phase will start, ending December 19. This will see the closure of the roundabout junction with Tebourba Way (southbound) and the slip-road onto Millbrook Road West.

Phase three, from January 7 to March, will require the shutting off of the slip-road from Millbrook Road West on to the roundabout, as well as the exit from the roundabout onto First Avenue – which leads to Dock Gate 20.

Phase four, from March to late-April, will see the closure of First Avenue (northbound) up to the roundabout and part of the slip-road onto Redbridge Road up to the junction with Second Avenue.

The council spokesperson added that January to March is a “quieter time for the port” and “the only time when it would be possible” to close access into Dock Gate 20 for work to be completed. However, the authority has confirmed that No works are planned to take place over Christmas. Millbrook flyover will also remain fully open throughout the works.

Cllr Jacqui Rayment, city transport chief, said: “Millbrook Roundabout is a road of national and local significance, serving both the city centre and the busy container port. We must invest now to secure a sustainable and successful future for Southampton.

"We are making every effort to minimise the impact on residents and commuters. Closures and diversions are clearly signposted and are detailed on our website.

"If you’re thinking about alternate ways to travel, by public transport, cycling or walking, make sure you check out the My Journey website and social media.

“Please bear with us as we carry out this essential work.”

The authority says that surveys undertaken found that a “complete renovation was needed” to “ensure a road of high importance to the local and national economy was kept fit for the future”.

The majority of the scheme’s cost, £5 million, has come from from the Department for Transport, with Southampton City Council contributing £3.3 million to meet the total cost of the scheme.

As reported, the work will start immediately after the boat show and the closure of the M27 for Highways England’s Romsey Road Bridge replacement scheme on the weekend of the September 28-30.

The proposed Highways England improvement project on Redbridge Roundabout is scheduled to begin in April 2019, once Millbrook Roundabout is complete.