Waka Kotahi NZ Transport Agency advises that work is about to start on significant road layout changes on State Highway 1 (SH1) at the Johnstone Hill tunnels.

On the night of Wednesday 30 September, both northbound and southbound tunnels will be closed for maintenance. This is part of regular maintenance to ensure the Auckland motorway network is kept in a good and safe condition for all road users.

The tunnels will be closed from 8.00 p.m. to 5.00 a.m. with traffic diverted to the Hibiscus Coast Highway. This effectively closes the motorway toll road between the Silverdale interchange and Pūhoi. Motorists are advised to allow an extra 15 minutes for the journey.

“Motorists are encouraged to plan ahead, allow extra time for their journey. The night-time closures are to minimise disruption when traffic is light. We appreciate your cooperation and apologise for any inconvenience.”

The scheduled changes are part of a staged sequence of work to connect SH1 to the new Ara Tūhono - Pūhoi to Warkworth motorway under construction north of the Johnstone Hill tunnels. There will be changes to the alignment of SH1 and new lanes will be added north of the tunnels before the 18.5km motorway is due to open in May 2022.

The motorway extension will vastly improve the safety, connectivity and resilience of the transport network between Northland and Auckland, helping to boost the economic potential of the Northland region.