AECOM New Zealand Limited
+64 4 896 6000
tel
Level 19, 171 Featherston Street
+64 4 896 6001
fax
Wellington 6011
PO Box 27277
Wellington 6141
New Zealand
www.aecom.com
31 August 2021
Commercial-in-Confidence
Senior Project Manager, Speed and Infrastructure Programme
Transport Services
Email: [email address]
1982
Phone: s 9(2)(a)
Mobile: s 9(2)(a)
Waka Kotahi NZ Transport Agency
Act
Auckland, Level 5, AMP Tower, 25 Customs Street West
Waikato Expressway Greenhouse Gas Emission Changes
Introduction
Waka Kotahi has commissioned AECOM NZ Limited to provide Greenhouse Gas (GHG)1 emissions
estimates for the Waikato Expressway 110km/h project. This document examines the use of a higher
maximum speed limit of 110km/h on the Expressway between Hampton Downs and Tamahere. The
GHG emissions estimate for the project are based on the predicted traffic modelling data provided by
Waka Kotahi. The Vehicle Emissions Prediction Model (V.6.2: 2021)2, was used to calculate the effect
that an increase to a 110km/h speed limit will have along the new Hamilton bypass section to
Hampton Downs on GHG emissions from vehicles using this section of expressway.
Information
Infrastructure investigated
The Waikato Expressway, a length of approximately 64.1 km, is being investigated for an increase to a
110km/h speed limit. The GHG analysis was undertake on the following sections of the expressway.
For reference a schematic of the route is also included in Appendix A.
Hampton Downs to Te Kauwhata
Official
Te Kauwhata to Rangiriri
Rangiriri to Ohinewai
Ohinewai to Huntly Section
the
Huntly Section
Ngaruawahia Section (only as far south to interface with the northern extent of the Hamilton
bypass)
Hamilton bypassunder
Tamahere section (between southern extent of the Hamilton bypass to the
Tamahere/Cambridge 110km/h interface
Released
1 Following the UNFCC Kyoto Protocol six main greenhouse gases were identified including carbon dioxide (CO2), methane
(CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PCFs), and sulphur hexafluoride (SF6). Of the main
six gases for Waka Kotahi carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O) are most likely to be important for
consideration in emission estimates.
2 Vehicle emissions prediction model | Waka Kotahi NZ Transport Agency (nzta.govt.nz)
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr
waikato expressway greenhouse gas emission change1 (010) - le.docx
Scope of work
The scope of work covers:
Enabled emissions from the increase in speed limit. These are the GHG emissions that arise
from use of the infrastructure. Sources of enabled emissions include emissions from vehicles
(including cars, buses, trucks, and trains), using the transport system.
1982
Model GHG emissions expressed as Carbon Dioxide Equivalents (CO2e)3 using the Vehicle
Emissions Prediction Model provided by Waka Kotahi.
Model traffic flows based on Annual Average Daily Traffic (AADT) and the percentage of
Act
Heavy Vehicles (HV) relating to a design year between 2031 and 2041, provided by Waka
Kotahi.
Model two scenarios for each design year 2031 and 2041:
o
GHG emissions estimated for the existing 100km/h maximum speed limit
o
GHG emissions estimated for the proposed 110km/h maximum speed limit
Summarise results in a memo, detailing the model parameters, and presenting a table of
corridor sections with a column for each scenario listed above (this memo).
Method summary
Information
The model developed uses the AADT, details of the vehicle fleet content and distances provided by
Waka Kotahi to calculate the Vehicle Kilometres Travelled (VKT) breakdown for each section of the
expressway in the predicted years. The VKT and speed data is then multiplied by the VEPM (version
6.2) estimate of vehicle fleet emissions predicted in the design year to calculate the emissions tonnes
CO2e (or tCO2e). Finally, the change in emissions due to the increased speed limit and the percentage
change are then calculated.
Official
the
under
Released
3 For any quantity and type of greenhouse gas, carbon-dioxide equivalent (CO2e) signifies the amount of CO2 which would have
the equivalent global warming impact. The carbon dioxide equivalent is calculated using the mass of a given GHG multiplied by
its global warming potential.
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr waikato expressway greenhouse gas emission
change1 (010) - le.docx
2 of 7
AECOM New Zealand Limited
+64 4 896 6000
tel
Level 19, 171 Featherston Street
+64 4 896 6001
fax
Wellington 6011
PO Box 27277
Wellington 6141
New Zealand
www.aecom.com
Results Summary
The full results for the modelled scenario are shown in Table 1 Expressway Section Data Summary.
The findings include:
An increase in the average fleet speed from 100 km/hr to the proposed 110 km/hr results in a
predicted increase in annual emissions of 4,324 tCO2e and 3,257 tCO2e for years 2031 and 2041
respectively
1982
An increase in average fleet speed to 110km/hr results in a predicted increase of 4.34% and 3.77%
in GHG emissions for years 2031 and 2041 when compared to 100km/h
The increase in the average fleet speed to 110km/hr results in a cumulative increase in GHG
emissions over the 2031 to 2041 period from 929,684 to 967,586 tCO
Act
2e, an increase of 37,903
tCO2e, or 4.08%
The main reason for the predicted increase in GHG emissions is due to light vehicles (e.g. passenger
vehicles) operating further beyond optimal fuel efficiency of around 80km from 100 km/hr to 110 km/hr.
Results show the increase in GHG emissions due to the increase in speed to 110km/hr is slightly reduced
by changes in the make-up of the New Zealand vehicle fleet between 2031 and 2041. The increase in GHG
emissions is smaller for 2041 when compared to 2031 because of the higher proportion of electric vehicles
in the light vehicle fleet that reduces the average emissions of the fleet.
Assumptions
1. All assumptions included in the Waka Kotahi VEPM (V6.2) default values, such as:
Information
a. Heavy commercial vehicles are travelling at a maximum of 86 km/hr
b. Heavy commercial vehicle load is 50%
c. An ambient temperature of 13.1 degrees Celsius
d. The road gradient is 0%
Official
2. The results assume the proportion of Heavy/ Light Vehicles and the subgroups within those
based on the data and traffic modelling provided by Waka Kotahi is an accurate
representation of the traffic along the sections of expressway.
the
3. The AADT provided by Waka Kotahi is an accurate average of the traffic throughout the year
4. All light vehicles travelling along the expressway will travel at the relevant maximum speed
limit
5. The speed limit is maintained throughout the expressway sections examined
under
6. VEPM predicted emissions from vehicles in the New Zealand fleet under typical road, traffic
and operating conditions. Emissions factors are based on predicted fleet average emissions.
Released
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr
waikato expressway greenhouse gas emission change1 (010) - le.docx
AECOM New Zealand Limited
+64 4 896 6000
tel
Level 19, 171 Featherston Street
+64 4 896 6001
fax
Wellington 6011
PO Box 27277
1982
Wellington 6141
New Zealand
www.aecom.com
Table 1 Expressway Section Data Summary
Act
Cumulative Cumulative
Total Annual tCO2e @
Total Annual tCO2e @
Change in Emissions
Percentage Change
Change in
Percentage
Section (between
Distance
existing 100 km/hr
proposed 110km/hr
tCO2e
in Emissions
Emissions
Change in
Interchanges)
(km)
tCO2e
Emissions
Predicted
Predicted
Predicted
Predicted
Predicted
Predicted
Predicted
Predicted
Predicted
Predicted
2031
2041
2031
2041
2031
2041
2031
2041
2031-2041
2031-2041
Hampton Downs to Te
8.1
15,364.15
12,853.43
16,056.56
13,362.62
692.41
509.19
4.51%
3.96%
6,008.00
4.26%
Kauwhata
Te Kauwhata to
2.1
3,448.74
3,041.45
3,604.17
3,161.94
155.42
120.49
4.51%
3.96%
1,379.55
4.25%
Rangiriri
Information
Rangiriri to Ohinewai
7.6
13,666.88
12,155.72
14,282.79
12,637.27
615.92
481.55
4.51%
3.96%
5,487.35
4.25%
Ohinewai to Huntly
1.3
2,252.36
1,972.85
2,353.86
2,051.00
101.51
78.15
4.51%
3.96%
898.30
4.25%
Section
Huntly Section
15.3
20,124.63
18,357.67
20,956.55
19,010.71
831.91
653.03
4.13%
3.56%
7,424.74
3.86%
Ngaruawahia Section
Official
7.4
16,637.26
13,796.90
17,432.25
14,385.65
794.99
588.74
4.78%
4.27%
6,918.67
4.55%
(to Lake Road)
Hamilton Section
Lake Road to
the
3.9
Resolution
4,961.06
3,780.54
5,166.15
3,915.02
205.08
134.48
4.13%
3.56%
1,697.83
3.88%
Resolution to Greenhill
7.2
6,764.28
6,373.00
6,994.01
6,551.81
229.73
178.81
3.40%
2.81%
2,042.70
3.11%
Greenhill to Ruakura
4.1
6,208.90
5,308.48
6,465.57
5,497.32
256.66
188.84
4.13%
3.56%
2,227.51
3.87%
Ruakura to Tamahere
4.9
5,661.44
4,981.86
5,870.47
5,136.30
209.03
154.44
3.69%
3.10%
1,817.32
3.41%
Tamahere to Airport
under
1.9
Road
4,561.56
3,663.61
4,792.88
3,832.41
231.32
168.81
5.07%
4.61%
2,000.64
4.86%
Column Totals
64
99,651
86,285
103,975
89,542
4,324
3,257
4.34%
3.77%
37,903
4.08%
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr
waikato expressway greenhouse gas emission change1 (010) - le.docx
Released
AECOM New Zealand Limited
+64 4 896 6000
tel
Level 19, 171 Featherston Street
+64 4 896 6001
fax
Wellington 6011
PO Box 27277
Wellington 6141
New Zealand
www.aecom.com
Closing Statement
This document outlines the predicted changes in greenhouse gas emissions (tCO2e) caused by a
change in the maximum speed limit on the Waikato Expressway from 100km/hr to 110km/hr. The
method uses the Vehicle Emissions Prediction Model to estimate the enabled emissions. Results
show it is estimated that there will be an increase of 4,324 and 3,257 tCO2e for year 2031 and 2041
respectively. This is a cumulative increase from 929,684 to 967,586 tCO2e in the period 2031 to 2041, or
1982
increase of 37,903 tCO2e, 4.08%.
Act
Yours faithfully
s 9(2)(a)
Team Leader Sustainability & Resilient Consultant
s 9(2)(a)
@aecom.com
Information
Mobile: s 9(2)(a)
Direct Fax: s 9(2)(a)
© AECOM New Zealand Limited (AECOM). All rights reserved.
AECOM has prepared this document for the sole use of the Client and for a specific purpose, each as expressly stated in the document. No other
party should rely on this document without the prior written consent of AECOM. AECOM undertakes no duty, nor accepts any responsibility, to any
Official
third party who may rely upon or use this document. This document has been prepared based on the Client’s description of its requirements and
AECOM’s experience, having regard to assumptions that AECOM can reasonably be expected to make in accordance with sound professional
principles. AECOM may also have relied upon information provided by the Client and other third parties to prepare this document, some of which
may not have been verified. Subject to the above conditions, this document may be transmitted, reproduced or disseminated only in its entirety.
the
under
Released
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr
waikato expressway greenhouse gas emission change1 (010) - le.docx
Limitations
AECOM New Zealand Limited (AECOM) has prepared this report in accordance with the usual care
and thoroughness of the consulting profession for the use of
Waka Kotahi and only those third parties
who have been authorised in writing by AECOM to rely on this Report. It is based on generally
accepted practices and standards at the time it was prepared. No other warranty, expressed or
implied, is made as to the professional advice included in this Report. It is prepared in accordance with 1982
the scope of work and for the purpose outlined in the contract dated
13th August 2021.
Where this Report indicates that information has been provided to AECOM by third parties, AECOM
has made no independent verification of this information except as expressly stated in the Report.
AECOM assumes no liability for any inaccuracies in or omissions to that information. This Report was
Act
prepared in
August 2021 and is based on the information reviewed at the time of preparation.
AECOM disclaims responsibility for any changes that may have occurred after this time. This Report
should be read in full. No responsibility is accepted for use of any part of this report in any other
context or for any other purpose or by third parties. This Report does not purport to give legal advice.
Legal advice can only be given by qualified legal practitioners. Except as required by law, no other
party should rely on this document without the prior written consent of AECOM. Where such
agreement is provided, AECOM will provide a letter of reliance to the agreed third party in the form
required by AECOM. To the extent permitted by law, AECOM expressly disclaims and excludes
liability for any loss, damage, cost or expenses suffered by any third party relating to or resulting from
the use of, or reliance on, any information contained in this Report. AECOM does not admit that any
action, liability or claim may exist or be available to any third party. It is the responsibility of third
Information
parties to independently make inquiries or seek advice in relation to their particular requirements and
proposed use of the information.
Official
the
under
Released
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr waikato expressway greenhouse gas emission
change1 (010) - le.docx
2 of 7
Appendix A
1982
Act
Information
Official
the
under
Released
\\na.aecomnet.com\lfs\apac\auckland-nzakl1\legacy\projects\606x\60644087\400_technical\480_nzup ghg\final files\waikato expressway\ltr waikato expressway greenhouse gas emission
change1 (010) - le.docx
3 of 7
