At the northern end of Transmission Gully, the new motorway connects with the existing SH1 (Kāpiti Expressway) just north of the Mackays Crossing interchange.
The new interchange at Pāuatahanui connects the new motorway via SH58 to the Hutt Valley in the east and Paremata in the west, around the Pāuatahanui Inlet.
The Waitangirua Interchange connects the communities of Whitby and Waitangirua with the motorway, via two new link roads being constructed by Porirua City Council.
The Kenepuru Interchange connects Porirua city centre and Tawa with the Transmission Gully motorway, via a new link road which crosses the existing SH1 and North Island Main Trunk railway line at Kenepuru.
