Motorists heading north should expect delays tomorrow and Wednesday as an emergency exercise and key maintenance is completed on the Northern Gateway toll road.
The State Highway 1 toll road will remain open at all times, but one of the two tunnels will be closed on both days and traffic diverted through the other tunnel.
The northbound tunnel will be closed from 4am on Tuesday until 4am Wednesday and people driving north will use the southbound tunnel. The following day the southbound tunnel will be closed from 4am until 6am Thursday and drivers going south diverted into the northbound tunnel.
New Zealand Transport Agency state highways manager for Auckland and Northland, Tommy Parker, said the diversions were necessary to ensure the tunnels are kept "in a good and safe condition".
"As the tunnels have sophisticated safety measures, it is important that they are regularly checked and maintained at a high level."
These features include 12 extraction fans, 1280 lights, 14 emergency equipment cabinets, two cross passages to move people from one tunnel to the other if there's an emergency, a deluge fire system, a pa system and 10 cctv cameras to monitor traffic.
On Wednesday night NZTA contractors, the Auckland Motorway Alliance and emergency services will conduct a small-scale emergency exercise in the southbound tunnel.
Parker said motorists needed to be aware of the diversions and speed restrictions as they approached the tunnels and advised they take "extra care in the tunnels themselves, which they will be sharing with oncoming traffic".
Two alternatives routes are also available - the Hibiscus Coast Highway between Puhoi, Orewa and the Silverdale interchange on SH1, and SH16 between Wellsford and the Silverdale interchange.
For updates and information about these works, or any other motorway issues please call Auckland Motorways on 09 5200 200.
- © Fairfax NZ News
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