Part of SH1 potentially to be raised to 110kmh speed limit

Thursday, 24 August 2023

Parts of State Highway 1 may be getting a speed limit raise to 110kmh. (file photo)

Reviews are underway for parts of State Highway 1 to potentially receive 110kmh speed limits, but Transmission Gully is not on the list.

Two expressways north of Wellington – from Mackay’s Crossing to Peka Peka, and then from Peka Peka to Ōtaki – are being reviewed to see if the speed limit can be increased to 110kmph.

Waka Kotahi regional relationships director Emma Speight said the intention was for a decision to be made early next year.

“The review, along with public consultation, will see if it is appropriate to increase the speed limit on these expressways without compromising driver safety. We can consider increasing the posted speed limit when a road is designed and constructed to modern safety standards.”

Transmission Gully would not be included in the current reviews.

“While Te Aranui o Te Rangihaeata – Transmission Gully is also built to the same high safety and operational standards, and early indications are that the crash numbers reflect the same improvement in safety, its speed management review will not start until its remaining project works are finished.

“Technical and safety reviews and public consultation would also need to be completed before any increase to its posted speed limit could be considered.”

Safety features on the expressways included median and shoulder barriers, two lanes in each direction, and the removal of crossroads and tight curves.

There were more than 1000 crashes between 2008 and 2022 on the old highway route before the new sections of SH1, Speight said. Of those, 10 were fatal and 55 were serious.

The number of crashes on the new expressway between Mackays Crossing and Peka Peka had fallen dramatically following the opening in 2017, with 166 crashes have been recorded, no fatal crashes and seven serious crashes.

If the decision to raise the limits goes through, the sections of SH1 will become the third and fourth roads to receive the higher limit, after the Waikato Expressway and Tauranga Eastern Link (TEL) motorway.

Transmission Gully was first talked about in 1919. Nearly 100 years later, plans were in place to build the motorway, and as of March 31, it's actually open.

The new limit was the result of a law change in 2017 following an NZTA speed management review the previous year.

The 2016 review not only allowed for the increase of limits on four lane highways, but also for sections of state highway to have their speed decreased in 20kmh increments.

The Setting of Speeds 2017 law was then expanded upon in 2022 and both have since led to the installation of wire median barriers and lower speed limits that have caused controversy in some parts of the country - most notably the lower limit between Napier and Taupo.

At the time, then associate transport minister Tim Macindoe said the limit would only apply to “stretches of roads built to a standard where the higher speed limit is both safe and appropriate.'

“This includes having at least two lanes in each direction, a median barrier, no significant curves and no direct access to neighbouring properties.”

The change was rolled out in late 2017, with the TEL and the Cambridge section of the Waikato Expressway getting the new limit.

By 2022, the final section of the Waikato Expressway was opened and the new limit was incorporated across the majority of the expressway from Hampton Downs to south of Cambridge.

At the time, more motorways were identified by NZTA as fulfilling the criteria for the new limit including the Auckland Northern Motorway from Oteha Valley Rd to the Johnstones Hill Tunnels and the Upper Harbour Motorway.

ACT MP Simon Court had previously asked Minister of Transport David Parker whether Transmission Gully had been engineered to a 110kmph speed, to which Parker answered positively.

However, he said he had been advised by Waka Kotahi that the speed limit for Transmission Gully would remain at 100kmph until a speed management review could take place that indicated a higher speed limit would be safe and appropriate.