Upcoming closures and updated detour on SH1 between Silverdale and Johnstones Hill tunnels

Waka Kotahi NZ Transport Agency is updating motorists on the detour route for closures between Silverdale and Johnstones Hill tunnels.

The detour route will require motorists to travel along the old State Highway 1 to and from Warkworth for any northbound and southbound closures between Silverdale and Johnstones Hill Tunnels.

It’s the same route followed prior to the new motorway opening and we appreciate that it’s a long route to follow.

Please plan ahead with the Waka Kotahi Journey Planner, and allow extra time when you travel.

Journey Planner(external link)

Detour information

Traffic travelling northbound: The detour will start at Silverdale and finish at Warkworth. Please follow the recommended detour via Twin Coast Discovery Highway and the old State Highway 1 to Warkworth as motorists are unable to join the motorway after Johnstones Hill Tunnels.

Traffic travelling southbound: The detour will start at Warkworth and finish at Silverdale. Please follow the recommended detour via the old State Highway 1 and Twin Coast Discovery Highway to the Silverdale southbound on-ramp as motorists are unable to exit the motorway before Johnstones Hill Tunnels.

Upcoming closures

The next planned full closures between Silverdale and Johnstones Hill Tunnels are:

• SH1 Johnstones Hill Tunnels full northbound closure on Sunday 17 and Monday 18 September between 9pm and 5am. Traffic will still be able to travel north through the tunnel using one of the southbound lanes.
• SH1 full northbound closure from Silverdale to Johnstones Hill Tunnels on Tuesday 19 September between 9pm and 5am. Detour required from Silverdale to Warkworth.
• SH1 full southbound closure from Johnstones Hill Tunnels to Silverdale on Wednesday 20 September between 9pm and 5am. Detour required from Warkworth to Silverdale.
• SH1 Johnstones Hill Tunnels full southbound closure on Thursday 21 September between 9pm and 5am. Traffic will still be able to travel south through the tunnel using one of the northbound lanes.