At the southern end of the Transmission Gully motorway, the new Kenepuru Interchange will provide the local community of Porirua safe access to and from the new motorway, via a new connector road, which travels over the existing SH1 and the North Island Main Trunk railway line at Kenepuru.
As we move closer to opening the new motorway, and the interchanges start to take shape, we’ll take a closer look at each. A spotlight on Kenepuru is the first in a series of information articles to give road users details on how the interchanges will work.
Finishing works have begun in the Kenepuru and Linden areas; one of the most complex sections of the Transmission Gully motorway project.
In this area the construction team has been challenged to build a new motorway around an older one while keeping State Highway 1 open to traffic. It’s also involved working very close to suburban streets and local businesses. The large northbound bridge to access the new motorway, Kenepuru link road bridge and new Collins Avenue overbridge are all on track and in the final stages of construction.
Preparatory works for the Kenepuru Drive roundabout are underway where we’re building up ground levels to meet up and tie into the local road. This work will start to interface with local road users later in the year, and will involve some temporary traffic management measures. When we are close to starting these works, we’ll update the community on the plans to keep local traffic moving as smoothly as possible. Pedestrians will be provided for as well. Works in the area will be ongoing until the end of the year, to keep us on schedule to open the new motorway in 2020.
Here’s how the different bridges and roundabouts work together to form the new Kenepuru Interchange.
SH1 Northbound at Kenepuru (from Wellington)
Northbound traffic will have two choices when approaching the new Kenepuru Interchange. The existing two northbound lanes will widen to three lanes south of the interchange and then traffic will split across four lanes at the interchange, in the same way that SH1 and SH2 split at Ngauranga. The two left-lanes will carry traffic seamlessly onto the new motorway, while the two right-lanes will carry traffic towards Porirua, Plimmerton and other northern suburbs via the existing SH1 network of interchanges and local roads.
- Bear left for Transmission Gully motorway.
- Bear right for existing SH1 to Porirua, Plimmerton and other northern suburbs.
Northbound traffic on Kenepuru Drive (from Tawa and Linden)
Northbound traffic on Kenepuru Drive will have two choices when they reach the new Kenepuru Drive roundabout.
- Take the first exit to stay on Kenepuru Drive and travel directly to Porirua.
- Take the second exit to connect with Transmission Gully via either the northbound motorway on-ramp towards Kāpiti, Pauatahanui and Whitby or the southbound on-ramp towards Wellington.
Southbound traffic on Kenepuru Drive (from Porirua)
Southbound traffic on Kenepuru Drive will have two choices when they reach the new Kenepuru Drive roundabout.
- Take the first exit to connect with Transmission Gully to the north or south.
- Take the second exit to continue south on Kenepuru Drive towards Linden and Tawa.
Southbound traffic on Transmission Gully motorway (from the north including Kāpiti, Pauatahanui and Whitby)
Southbound traffic on Transmission Gully motorway can take the off-ramp to the Kenepuru Interchange to connect with Kenepuru Drive for Linden, Tawa or Porirua connections.
- Exit left off Transmission Gully motorway, take the second exit off the Kenepuru Interchange roundabout, head west to connect with the Kenepuru Drive roundabout.
- At the Kenepuru Drive roundabout take the first exit to connect with Linden and Tawa.
- At the Kenepuru Drive roundabout take the second exit to connect with Porirua.
Southbound traffic on SH1 (from Plimmerton, Porirua and other northern suburbs)
Southbound traffic from Porirua and other northern suburbs on the existing SH1 will merge with southbound Transmission Gully motorway traffic just south of the Kenepuru Interchange and continue southbound to Wellington.
- Merge with southbound Transmission Gully motorway traffic and continue travelling south on SH1.
Check out the animated video below to see the new Kenepuru Interchange in action.
Bridge 25 beam installation
Watch a timelapse of the installation of Bridge 25 on Tuesday, 12 March 2019.
Collins Avenue bridge demolition
Watch a timelapse of the demolition of the Collins Avenue bridge on Saturday, 3 November 2018.
Steel bridge girder installation – Kenepuru
Watch a timelapse of the installation of a section of steel bridge girders over the North Island Main Trunk railway line for the new Kenepuru connector road in December 2017.
Collins Avenue bridge 'super t' concrete beam installation
Watch a timelapse of the installation of four large ‘super t’ concrete beams for a section of the new Collins Avenue bridge in September 2017.
Watch an animation of the Kenepuru Interchange, where the Transmission Gully motorway route merges with State Highway 1 in the south, near Tawa.