50 Victoria Street
Private Bag 6995
Wellington 6141
New Zealand
T 64 4 894 5400
F
64 4 894 6100
www.nzta.govt.nz
19 February 2020
Tyler
[FYI request #12073 email]
Ref: NZT-4655
Dear Tyler
Request made under the Official Information Act 1982
Thank you for your email
of 22 January 2020 to Auckland Transport requesting information under the
Local Government Official Information and Meetings Act 1987. On 29 January 2020, your request was
transferred to Waka Kotahi, the NZ Transport Agency, for response under the Official Information Act
1982 (the Act). Your request is quoted below:
“Can you please advise and disclose whether there is any correlation between the time of
day and the variable speed zone limit from Waterview to Kingsland on the SH16
Motorway.
Eg. From the Hours of A to B - Speed is 80kph (Southbound)
If so, is there any justification for this compared to decreasing speed during poor weather
and conditions.”
On weekdays, during the hours 5:30am to 10am and 3pm to 8pm, the speed limit on State Highway
16 (SH16) from Waterview to Kingsland is 80km/h. Outside of those hours, the speed limit is typically
100km/h.
The Transport Agency calculates speed limits by reference to the Speed Management Guide. The
Speed Management Guide is a document that helps modernise the approach to managing speed in
New Zealand. It supports a consistent approach to speed that is appropriate for road function, design,
safety, use and the surrounding environment. The Speed Management Guide is available at:
www.nzta.govt.nz/assets/Safety/docs/speed-management-resources/speed-management-guide-first-
edition-201611.pdf.
Following the above approach, the Transport Agency has determined the safe and appropriate speed
between Waterview and Kingsland to be 80km/h. This is mainly due to the corridor’s high collective
risk (a measure of the number of deaths and serious injuries per kilometre). Because the crashes are
predominantly rear-end and lane splitting type crashes, which generally occur in peak traffic
conditions, it is appropriate to have an 80km/h speed limit when traffic is heavy. We undertook traffic
analysis to assess when indicated peak periods occur and found that to be weekdays from 5:30am to
10am and 3pm to 8pm.
We also consider there to be safety benefits from decreasing speeds during poor weather and other
adverse conditions (such as a result of incidents, road works). This is applied at the discretion of the
Auckland Transport Operations Centre, depending on the severity and nature of the conditions.
2
If you would like to discuss this reply with the Transport Agency, please contact Jeremy O’Brien,
Manager Behaviour and Choice, by email to [email address] or by phone on 09 928 8794.
Yours sincerely
Neil Walker
Senior Manager, Journey Management Centre
