The closure was extended just before 8am, the cordon now stretching from Taurima St to Hamilton Rd for southbound traffic.
At 9am, the road was fully closed in both directions in Hataitai.
“This is to allow the bus, involved in this morning’s crash, to be towed away,” NZTA said.
“State Highway 1 will remain closed to traffic between Taurima Street and Hamilton Road while this work is completed. Drivers travelling through the area can detour via Taurima Street, Moxham Avenue, Kupe Street, and Hamilton Road.”
By 9.20am the northbound lane had reopened.
Travel delays can be expected until this incident is fully resolved. Drivers must allow for extra travel time.
The highway was originally closed to southbound traffic between Moxham Ave and Hamilton Rd.
The NZTA spokesperson said traffic would be especially troublesome for those trying to head to Wellington Airport and the Miramar peninsula.