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Wellington 6141
New Zealand
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www.nzta.govt.nz
19 January 2023
Richard Young
[FYI request #20297 email]
REF: OIA-11614
Dear Richard
Request made under the Official Information Act 1982
Thank you for your email of 30 November 2022 requesting the fol owing information under the Official
Information Act 1982 (the Act):
[…] I thought the OIA was very clear in the information being sought, and nothing you have
provided to date answers it, so for a final time:- 'Please can you therefore provide the reports
that state this 17,000vpd figure and ALL supporting documents / communications /
calculations (digital / written) that were used to determine that 17,000 vpd figure.'
The information you have requested has already been provided to you in response to your previous
request for the same information (Ref: OIA-10818). There is no further material that would fal within
the scope of this request. Therefore, I refuse your request for further reports, communications and
calculations under section 18(e) of the Act as the document al eged to contain the information
requested does not exist or cannot be found. However, in order to provide reasonable assistance, an
explanation and background information is outlined below.
When developing the
‘Auckland Harbour Bridge Active Mode Provision – Traffic Impact Assessment,
June 2021’ report, Resolve and Auckland System Management (ASM) undertook model ing which
was then used to provide input into the November 2021 Investment and Delivery paper. The
November 2021 Investment and Delivery paper states that,
‘model ing suggests a dedicated single
walking and cycling lane would require a significant reduction in daily traffic volumes on the bridge to
have a neutral effect on the wider Auckland transport system (greater than 17,000. vehicles per day or
a 10% reduction)’.
It is not possible to predict with certainty how demand reduction behaviour wil change due to
additional traffic volumes likely to be created by implementing an active mode facility that would
reduce traffic capacity on the Auckland Harbour Bridge (AHB), and so demand reduction needs to be
considered an unknown variable.
Four demand reduction scenarios were developed for use as inputs to model the potential impacts of
behavioural change on traffic volumes on the AHB. These scenarios were calculated using a
combination of factors, including, but not limited to, patrons shifting their journeys to active modes or
public transport, or re-routing or re-timing of trips.
The Level 1 demand reduction scenario (found on page 28 of attachment 6, OIA-10818) corresponds
to the lowest anticipated behavioural change, where traffic model ing wil reflect a limited shift in usage
and resulting traffic volumes wil be higher than current volumes. The Level 4 demand reduction
scenario corresponds to the highest level of behavioural change where the number of people who
would need to modify their journey is sufficient to provide traffic volumes on the AHB which are almost
equivalent to its current state. Both of these scenarios are provided to you again as an appendix at the
end of this letter.
The total area in green for the Level 4 scenario is reflective of the mode shift scenario required to
result in a “neutral” effect on traffic volumes on the AHB. This is equal to approximately 19,000
vehicles per day and was calculated using the Level 4 modal shift scenario numbers, provided in
Table 4, which can be found on page 26 of the
Auckland Harbour Bridge Active Mode Provision –
Traffic Impact Assessment, June 2021. Level 4 is a conservative estimate, and traffic demand on the
AHB is less on weekends. It was therefore determined that the 19,000 figure should be reduced to
account for this decreased demand, resulting in the 17,000 daily number quoted in the 2021
Investment and Delivery Committee report.
Under section 28 of the Act, you have the right to ask the Ombudsman to review my decision with
regards to this request. The contact details for the Ombudsman can be located at
www.ombudsman.parliament.nz.
If you would like to discuss this reply with Waka Kotahi, please contact Ministerial Services by email to
[NZTA request email].
Yours sincerely
Robyn Elston
National Manager System Design
2
Appendix 1 – Level 1 and 4 demand reduction scenarios:
3