Preparation work on the new $43 million Haywards Interchange, north of Wellington, is about to begin ahead of construction kicking off in October.

It's time to wave goodbye to those pesky traffic lights that have slowed down your journey between Wellington and Upper Hutt.

Construction will kick off in a matter of weeks on a new interchange at the intersection of State Highways 2 and 58 where motorists currently spend a large chunk of their daily commute camped in large queues at traffic lights.

The $43 million Haywards Interchange will be the biggest roading project undertaken in the Hutt Valley for some years.

Once complete in about two years' time, it will look similar to the Dowse interchange, which was finished in 2010.

It will essentially be an elevated roundabout with a new "park and ride" car park for Manor Park railway station and a pedestrian bridge linking the two. New cycleways heading both north and south will be built on either side.

The main benefit of the interchange is that it will remove the troublesome SH2-SH58 intersection, meaning traffic using SH2 will no longer have to give way to those using the Haywards Hill Rd between Hutt Valley and Porirua.

The large queues of traffic that form there, particularly during peak times, make it a safety hazard. Between 2009 and 2013 it was the site of 119 crashes.

Neil Walker, the New Zealand Transport Agency's Wellington highways manager, said the new Haywards Interchange would provide motorists with a safer and less frustrating journey between the capital and Hutt Valley.

"People who use this intersection frequently will know that it can be a real bottleneck, and that there's also a number of crashes and near misses when drivers get impatient or make mistakes," he said.

"This project will effectively put those problems behind us."

Cyclists using SH2 would also no longer have to cross traffic lanes when passing through the intersection, he said.

"This is more than just a roading project. All travellers will benefit, whether you're taking the train, hopping on a bike, or getting behind the wheel."

Upper Hutt Mayor Wayne Guppy said the Haywards Interchange would provide another major gateway into the Hutt Valley, alongside the future Transmission Gully motorway.

"It's a significant project for the users of SH58 and SH2 – not only in safety terms, but also in travel times from the Wairarapa and Upper Hutt into Wellington city."

Preparatory work on the new interchange will begin next week, ahead of construction beginning in a few weeks' time.