The new motorway from Cranford St to near the Waimakariri River Bridge will be open to traffic for an initial period of two weeks.
New Zealand Transport Agency spokeswoman Frances Adank said the northbound QEII Drive lane of the motorway opened this morning.
The Cranford St end opened at 9.30am and the south side of the Waimakariri Bridge end at 10am.
The partial opening is to help bed in the chip seal surface. Due to the loose gravel a temporary 50km/h speed limit will be in place.
It follows a delay to the partial opening of the motorway which was expected on Monday but postponed due to bad weather.
From December 1 to December 11, one traffic lane in each direction will be open.
Northbound traffic can choose the CNC as an option between 7am and 4pm, southbound traffic can use the CNC between 10am and 6pm.
The lanes will shift during the day so all four lanes are used.
On December 12, 2pm-6pm, NZTA is planning an open day, where people can walk or cycle the motorway.
After the open day, the motorway will be closed to allow the finishing touches to be put on it ahead of its full opening on December 17.
