Kia ora Nigel

 

This email acknowledges your below request for information made under the
Official Information Act 1982.

 

Your request has been forwarded to the appropriate section of NZ Transport
Agency Waka Kotahi for response. They will contact you if they require
clarification of your request, more time to respond, or if your request
has been transferred to another organisation to respond to. Unless more
time is required, NZ Transport Agency will send a response to you within
20 working days of receiving your request – in this instance on or before
25 June 2026.

 

If you would like to discuss your request with NZ Transport Agency, please
contact us by email at [1][NZTA request email].

 

Ngā mihi

 

Ministerial Services
Te Waka Kōtuia | Engagement & Partnerships
NZ Transport Agency Waka Kotahi

[2]Connect with us on Social Media

 

[3][IMG]

 

 

 

-----Original Message-----
From: Nigel Gray <[FOI #34723 email]>
Sent: Sunday, 17 May 2026 10:58 am
To: Official Correspondence <[email address]>
Subject: Official Information request - Traffic‑Signal Outages, Crash
Risk, and System Capability

 

[You don't often get email from
[4][FOI #34723 email]. Learn why this is
important at [5]https://aka.ms/LearnAboutSenderIdentific... ]

 

Dear New Zealand Transport Agency,

Kia ora,

 

I am requesting the following information under the Official Information
Act 1982.

 

1. Research, studies, or analysis held by Waka Kotahi Please provide all
documents, reports, internal analyses, briefings, memos, emails, or data
extracts relating to:

 

The relationship between traffic‑signal outages (planned or unplanned) and
traffic‑crash frequency or severity.

 

Any assessment of whether crash rates increase, decrease, or remain
unchanged during periods when traffic signals are non‑operational.

 

Any monitoring, modelling, or risk assessments involving signal‑failure
events and road‑safety outcomes.

 

If Waka Kotahi holds no such research, please confirm this explicitly.

 

2. International evidence held or reviewed by Waka Kotahi Please provide:

 

Any literature reviews, international research summaries, or comparative
assessments relating to crash risk during traffic‑signal outages.

 

Any documents referencing overseas findings (e.g., Netherlands, UK, Japan,
US) where signal outages or deliberate signal removal were associated with
changes in crash rates or driver behaviour.

 

Any internal consideration of whether such international findings have
implications for New Zealand’s road‑safety framework.

 

If Waka Kotahi has never reviewed international evidence on this topic,
please confirm this.

 

3. Data held on traffic‑signal outages

For the period 1 January 2010 to the present, please provide:

 

Any datasets, logs, or records of traffic‑signal outages, including date,
time, duration, and location.

 

Any metadata describing how outages are recorded, categorised, or stored.

 

Any documents describing how outage data is used operationally or
analytically.

 

If Waka Kotahi does not hold this information, please identify the agency
that does.

 

4. Crash Analysis System (CAS) capability and limitations Please provide:

 

The list of CAS variables relevant to intersections and traffic‑control
devices.

 

Confirmation of whether CAS includes any field that captures signal‑status
(e.g., “lights out”, “malfunctioning”, “flashing”, “power outage”).

 

Any internal guidance, schema documents, or data dictionaries describing
how CAS handles traffic‑control device failures.

 

Any documents discussing the feasibility, limitations, or implications of
analysing crash risk during signal outages using CAS.

 

If CAS has no ability to record signal‑status, please confirm this
explicitly.

 

5. Internal consideration of the issue

Please provide any documents, emails, or internal discussions relating to:

 

Whether Waka Kotahi has ever considered studying the safety impact of
traffic‑signal outages.

 

Whether such analysis has been proposed, rejected, deferred, or deemed
unnecessary.

 

Any reasoning provided for not undertaking such analysis, if applicable.

 

6. Future plans or system upgrades

Please provide:

 

Any planned or proposed upgrades to traffic‑signal monitoring systems.

 

Any consideration of integrating signal‑status data with CAS or other
safety‑analysis tools.

 

Any documents relating to improving the ability to analyse safety outcomes
during signal‑failure events.

 

7. Clarification of responsibilities

Please identify:

 

Which agency or agencies are responsible for monitoring, recording, and
analysing traffic‑signal outages.

 

Which agency or agencies are responsible for assessing the safety
implications of such outages.

 

Format

Please provide all information in machine‑readable format (CSV, XLSX, or
searchable PDF) where possible.

 

Withholding grounds

If any information is withheld, please specify the exact grounds under
sections 6, 9, or 18 of the OIA and the public‑interest considerations
applied.

 

Ngā mihi,

Nigel Gray

 

Yours faithfully,

 

Nigel Gray

 

-------------------------------------------------------------------

 

This is an Official Information request made via the FYI website.

 

Please use this email address for all replies to this request:

[6][FOI #34723 email]

 

Is [7][NZTA request email] the wrong address for Official
Information requests to New Zealand Transport Agency? If so, please
contact us using this form:

[8]https://aus01.safelinks.protection.outlo...

 

Disclaimer: This message and any reply that you make will be published on
the internet. Our privacy and copyright policies:

[9]https://aus01.safelinks.protection.outlo...

 

If you find this service useful as an Official Information officer, please
ask your web manager to link to us from your organisation's OIA or LGOIMA
page.

 

 

-------------------------------------------------------------------

 

This message, together with any attachments, may contain information that
is classified and/or subject to legal privilege. Any classification
markings must be adhered to. If you are not the intended recipient, you
must not peruse, disclose, disseminate, copy or use the message in any
way. If you have received this message in error, please notify us
immediately by return email and then destroy the original message. This
communication may be accessed or retained by NZ Transport Agency Waka
Kotahi for information assurance purposes.

References

Visible links
1. mailto:[NZTA request email]
2. https://www.nzta.govt.nz/contact-us/conn...
3. https://nzta.govt.nz/
4. mailto:[FOI #34723 email]
5. https://aka.ms/LearnAboutSenderIdentific...
6. mailto:[FOI #34723 email]
7. mailto:[NZTA request email]
8. https://fyi.org.nz/change_request/new?bo...
9. https://fyi.org.nz/help/officers

hide quoted sections

Kia ora Nigel

 

Thank you for your e-mail of 17 May 2026 regarding information regarding
traffic signal outages in relation to crashes.  Your request is being
considered in accordance with the Official Information Act 1982.

 

We are writing with regard to the first and second parts of part 3, which
was for:

 

3. Data held on traffic‑signal outages

For the period 1 January 2010 to the present, please provide:

 

Any datasets, logs, or records of traffic‑signal outages, including date,
time, duration, and location.

 

Any metadata describing how outages are recorded, categorised, or stored.

 

Regarding the first part, to provide any data or records of traffic signal
outages for the timeframe requested would involve going through each day
file (365 files per year).  As the timeframe requested goes back at least
15 years, this part of your request would involve a significant amount of
collation, staff time and resources.   We therefore consider that the
first part of your request, as currently framed, cannot be met without
substantial collation and research and, unless it is refined, is likely to
be refused under section 18(f) of the Official Information Act.  To enable
us to help you, we would like you to refine the timeframe to a shorter
period – for example, a 12-month period from 1 May 2025 to 30 April 2026.

 

Regarding the second part, it is unclear what you mean by “metadata”.  Can
you please clarify if you are referring to a specific document or, for
instance, information on a specific website – or something else
altogether.

 

We look forward to being able to assist once these parts of your request
are defined.  It would be great to hear back from you by 4.00pm on Friday
22 May 2026.

 

Ngā mihi

 

Ministerial Services
Te Waka Kōtuia | Engagement & Partnerships
NZ Transport Agency Waka Kotahi

[1]Connect with us on Social Media

[2][IMG]

 

 

 

-----Original Message-----
From: Nigel Gray <[3][FOI #34723 email]>
Sent: Sunday, 17 May 2026 10:58 am
To: Official Correspondence <[4][email address]>
Subject: Official Information request - Traffic-Signal Outages, Crash
Risk, and System Capability

 

[You don't often get email from
[5][FOI #34723 email]. Learn why this is
important at [6]https://aka.ms/LearnAboutSenderIdentific... ]

 

Dear New Zealand Transport Agency,

Kia ora,

 

I am requesting the following information under the Official Information
Act 1982.

 

1. Research, studies, or analysis held by Waka Kotahi Please provide all
documents, reports, internal analyses, briefings, memos, emails, or data
extracts relating to:

 

The relationship between traffic‑signal outages (planned or unplanned) and
traffic‑crash frequency or severity.

 

Any assessment of whether crash rates increase, decrease, or remain
unchanged during periods when traffic signals are non‑operational.

 

Any monitoring, modelling, or risk assessments involving signal‑failure
events and road‑safety outcomes.

 

If Waka Kotahi holds no such research, please confirm this explicitly.

 

2. International evidence held or reviewed by Waka Kotahi Please provide:

 

Any literature reviews, international research summaries, or comparative
assessments relating to crash risk during traffic‑signal outages.

 

Any documents referencing overseas findings (e.g., Netherlands, UK, Japan,
US) where signal outages or deliberate signal removal were associated with
changes in crash rates or driver behaviour.

 

Any internal consideration of whether such international findings have
implications for New Zealand’s road‑safety framework.

 

If Waka Kotahi has never reviewed international evidence on this topic,
please confirm this.

 

3. Data held on traffic‑signal outages

For the period 1 January 2010 to the present, please provide:

 

Any datasets, logs, or records of traffic‑signal outages, including date,
time, duration, and location.

 

Any metadata describing how outages are recorded, categorised, or stored.

 

Any documents describing how outage data is used operationally or
analytically.

 

If Waka Kotahi does not hold this information, please identify the agency
that does.

 

4. Crash Analysis System (CAS) capability and limitations Please provide:

 

The list of CAS variables relevant to intersections and traffic‑control
devices.

 

Confirmation of whether CAS includes any field that captures signal‑status
(e.g., “lights out”, “malfunctioning”, “flashing”, “power outage”).

 

Any internal guidance, schema documents, or data dictionaries describing
how CAS handles traffic‑control device failures.

 

Any documents discussing the feasibility, limitations, or implications of
analysing crash risk during signal outages using CAS.

 

If CAS has no ability to record signal‑status, please confirm this
explicitly.

 

5. Internal consideration of the issue

Please provide any documents, emails, or internal discussions relating to:

 

Whether Waka Kotahi has ever considered studying the safety impact of
traffic‑signal outages.

 

Whether such analysis has been proposed, rejected, deferred, or deemed
unnecessary.

 

Any reasoning provided for not undertaking such analysis, if applicable.

 

6. Future plans or system upgrades

Please provide:

 

Any planned or proposed upgrades to traffic‑signal monitoring systems.

 

Any consideration of integrating signal‑status data with CAS or other
safety‑analysis tools.

 

Any documents relating to improving the ability to analyse safety outcomes
during signal‑failure events.

 

7. Clarification of responsibilities

Please identify:

 

Which agency or agencies are responsible for monitoring, recording, and
analysing traffic‑signal outages.

 

Which agency or agencies are responsible for assessing the safety
implications of such outages.

 

Format

Please provide all information in machine‑readable format (CSV, XLSX, or
searchable PDF) where possible.

 

Withholding grounds

If any information is withheld, please specify the exact grounds under
sections 6, 9, or 18 of the OIA and the public‑interest considerations
applied.

 

Ngā mihi,

Nigel Gray

 

Yours faithfully,

 

Nigel Gray

 

-------------------------------------------------------------------

 

This is an Official Information request made via the FYI website.

 

Please use this email address for all replies to this request:

[7][FOI #34723 email]

 

Is [8][NZTA request email] the wrong address for Official
Information requests to New Zealand Transport Agency? If so, please
contact us using this form:

[9]https://aus01.safelinks.protection.outlo...

 

Disclaimer: This message and any reply that you make will be published on
the internet. Our privacy and copyright policies:

[10]https://aus01.safelinks.protection.outlo...

 

If you find this service useful as an Official Information officer, please
ask your web manager to link to us from your organisation's OIA or LGOIMA
page.

 

 

-------------------------------------------------------------------

 

 

This message, together with any attachments, may contain information that
is classified and/or subject to legal privilege. Any classification
markings must be adhered to. If you are not the intended recipient, you
must not peruse, disclose, disseminate, copy or use the message in any
way. If you have received this message in error, please notify us
immediately by return email and then destroy the original message. This
communication may be accessed or retained by NZ Transport Agency Waka
Kotahi for information assurance purposes.

References

Visible links
1. https://www.nzta.govt.nz/contact-us/conn...
2. https://nzta.govt.nz/
3. mailto:[FOI #34723 email]
4. mailto:[email address]
5. mailto:[FOI #34723 email]
6. https://aka.ms/LearnAboutSenderIdentific...
7. mailto:[FOI #34723 email]
8. mailto:[NZTA request email]
9. https://fyi.org.nz/change_request/new?bo...
10. https://fyi.org.nz/help/officers

hide quoted sections

Kia ora Nigel

 

Thank you for your further e-mail of 19 May 2026 regarding your request
for information on traffic signal outages in relation to crashes, which is
being considered in accordance with the Official Information Act 1982.  We
are further writing with regard to the first and second parts of part 3,
which you refined and clarified respectively as follows:

 

3. Data held on traffic‑signal outages

 

Traffic‑signal outage datasets, logs, or records for the period 1 May 2025
to 30 April 2026, including date, time, duration, and location.

 

And:

 

By “metadata”, I am referring to:

 

any data dictionary, field definitions, or schema describing how
traffic‑signal outages are recorded in your system(s)

 

any classification rules, coding conventions, or system documentation that
explains how outages are categorised, stored, or updated

 

any system‑level metadata that describes the structure of the dataset
(e.g., field names, field types, units, code lists, or status categories)

 

Regarding the first part for data from 1 May 2025 to 30 April 2026, we
would like you to further clarify if you would be happy to receive just
the data held by NZ Transport Agency Waka Kotahi (NZTA).  To provide
context, some assets are owned by local councils, whereas others are owned
by NZTA.  This means that, if you are seeking data for the whole of New
Zealand, you would need to contact each local council – which includes
Christchurch and Wellington City Councils.  For instance, our Wellington
Transport Operation Centre (WTOC) can provide data for this timeframe for
our area of operation only (New Plymouth across to Hawkes Bay, and down to
Invercargill) – which excludes Wellington and Christchurch cities.  It is
also important to note that Auckland Traffic Operation Centre (ATOC),
which manages the Auckland region, manages some assets owned by NZTA
whereas others are owned by Auckland Transport (AT) – which means that we
can only provide data from NZTA-owned assets. 

 

Regarding the second part for “metadata”, we would like you to further
clarify if you would be happy to receive just the information pertaining
to NZTA.  To provide context, local roads are managed by local councils
(also known as Road Controlling Authorities (RCA)), whereas state highways
are managed by NZTA.  RCAs all use different incident recording system
which means that, if you are seeking information for the whole of New
Zealand, you would need to contact each local council.

 

We look forward to being able to assist once these parts of your request
are further defined.  It would be great to hear back from you by 4.00pm on
Monday 25 May 2026.

 

Ngā mihi
Chanell

 

Ministerial Services
Te Waka Kōtuia | Engagement & Partnerships
NZ Transport Agency Waka Kotahi

[1]Connect with us on Social Media

[2][IMG]

 

 

 

-----Original Message-----

From: Nigel Gray <[3][FOI #34723 email]>

Sent: Tuesday, 19 May 2026 7:07 pm

To: Official Correspondence <[4][email address]>

Subject: Re: OIA-22224 REQUEST FOR CLARIFICATION

 

Dear Official Correspondence,

Kia ora,

 

Thank you for your email of 19 May. I am happy to refine the request in a
way that avoids any unnecessary collation while still enabling access to
the information held.

 

1. Timeframe refinement

I accept your suggestion of refining the first part of item 3 to a
12‑month period. Please provide:

 

Traffic‑signal outage datasets, logs, or records for the period 1 May 2025
to 30 April 2026, including date, time, duration, and location.

 

2. Clarification of “metadata” 

By “metadata”, I am referring to:

 

any data dictionary, field definitions, or schema describing how
traffic‑signal outages are recorded in your system(s)

 

any classification rules, coding conventions, or system documentation that
explains how outages are categorised, stored, or updated

 

any system‑level metadata that describes the structure of the dataset
(e.g., field names, field types, units, code lists, or status categories)

 

This clarification should allow you to identify the relevant documents
without substantial collation or research.

 

Please let me know if you require anything further.

 

Ngā mihi,

Nigel Gray

 

Yours sincerely,

 

Nigel Gray

 

-----Original Message-----

 

Kia ora Nigel

 

 

 

Thank you for your e-mail of 17 May 2026 regarding information regarding 
traffic signal outages in relation to crashes.  Your request is being 
considered in accordance with the Official Information Act 1982.

 

 

 

We are writing with regard to the first and second parts of part 3, which 
was for:

 

 

 

3. Data held on traffic‑signal outages

 

For the period 1 January 2010 to the present, please provide:

 

 

 

Any datasets, logs, or records of traffic‑signal outages, including date, 
time, duration, and location.

 

 

 

Any metadata describing how outages are recorded, categorised, or stored.

 

 

 

Regarding the first part, to provide any data or records of traffic
signal  outages for the timeframe requested would involve going through
each day  file (365 files per year).  As the timeframe requested goes back
at least

15 years, this part of your request would involve a significant amount of 
collation, staff time and resources.   We therefore consider that the 
first part of your request, as currently framed, cannot be met without 
substantial collation and research and, unless it is refined, is likely
to  be refused under section 18(f) of the Official Information Act.  To
enable  us to help you, we would like you to refine the timeframe to a
shorter  period – for example, a 12-month period from 1 May 2025 to 30
April 2026.

 

 

 

Regarding the second part, it is unclear what you mean by “metadata”. 
Can  you please clarify if you are referring to a specific document or,
for  instance, information on a specific website – or something else 
altogether.

 

 

 

We look forward to being able to assist once these parts of your request 
are defined.  It would be great to hear back from you by 4.00pm on Friday

22 May 2026.

 

 

 

Ngā mihi

 

 

 

Ministerial Services

Te Waka Kōtuia | Engagement & Partnerships  NZ Transport Agency Waka
Kotahi

 

[1]Connect with us on Social Media

 

[2][IMG]

 

 

 

 

 

 

 

-------------------------------------------------------------------

Please use this email address for all replies to this request:

[5][FOI #34723 email]

 

Disclaimer: This message and any reply that you make will be published on
the internet. Our privacy and copyright policies:

[6]https://aus01.safelinks.protection.outlo...

 

If you find this service useful as an Official Information officer, please
ask your web manager to link to us from your organisation's OIA or LGOIMA
page.

 

-------------------------------------------------------------------

 

This message, together with any attachments, may contain information that
is classified and/or subject to legal privilege. Any classification
markings must be adhered to. If you are not the intended recipient, you
must not peruse, disclose, disseminate, copy or use the message in any
way. If you have received this message in error, please notify us
immediately by return email and then destroy the original message. This
communication may be accessed or retained by NZ Transport Agency Waka
Kotahi for information assurance purposes.

References

Visible links
1. https://www.nzta.govt.nz/contact-us/conn...
2. https://nzta.govt.nz/
3. mailto:[FOI #34723 email]
4. mailto:[email address]
5. mailto:[FOI #34723 email]
6. https://fyi.org.nz/help/officers

hide quoted sections