 It will complement the current State Highway 1 along the coast road between the Kapiti Coast, Pukerua Bay and Porirua.From SH1 at MacKays Crossing, north of Paekakariki, the route rises steeply to the Wainui Saddle and follows Transmission Gully down to Porirua Harbour's Pauatahanui Inlet.It continues south around the outer edge of the Porirua urban area, at one point crossing a 300-metre-long and 90-metre-high bridge, and rejoins SH 1 at the boundary of Porirua and Tawa.