Hear from those who are working directly with the latest policy and get an insight into the likely implications from Defra’s upcoming Air Quality Plan.

1. www.jacobs.com | worldwide
Greater Manchester’s CAZ
Hazel Peace
6th June 2017

2. Agenda
1. Introduction
2. Study overview
3. CAZ considerations
4. CAZ areas
5. Emissions and AQ impacts – screening
6. More detailed modelling
7. Conclusion and thoughts
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3. • England’s fastest growing large city
• Increase in population
• = Increase in road traffic
– Increase in congestion
– Increase in emissions
– Increase in PM, NO2, CO2
– Unless modal shift…
– Or zero emission vehicles
Greater Manchester 2040 vision
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GREATER MANCHESTER LOW-EMISSION STRATEGY
AND AIR QUALITY ACTION PLAN
PUBLIC CONSULTATION

4. • EU/UK NO2 limit/objective value – exceedance
likely
in 2020
• Significant
impact from
roads
• Feasibility study
to look at road
related CAZ
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Before 2040….?
http://www.gmtu.gov.uk/gam_maps/

5. • WP1 – Screening 
• WP2 – Refining of air quality estimates 
• WP3 – Refine economics ?
• WP4 – Refine health ?
• WP5 – Reporting ?
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Undertaken through work packages:

6. 6
CAZ Considerations Description Importance
Administrative boundary Where is the CAZ boundary? The location of the CAZ boundary is important
both in determining potential benefits and in order
to determine the potential costs and enforcement
methods
Class (vehicle types) Which CAZ class should apply? I.e. what vehicles
will be restricted within the CAZ boundary (and
subsequently people and businesses)? Which
vehicles will be exempt from meeting the CAZ
standards when within the CAZ boundary?
Which CAZ class is used affects both the
potential benefits that can be derived from the
CAZ and also effects the enforcement costs and
other socio-economic impacts.
Standards What should the minimum standards for a CAZ
be? Defra have used Euro V/6 (diesel) and Euro
4 (petrol LDV) standards for different CAZ
classes.
The standards that are targeted will affect the
actions taken to meet the CAZ requirements, with
lower standards more likely to result in vehicle
replacement by some (lower costs) but with
lesser impact
Hours of operation When will the CAZ standards need to be adhered
to?
There are different implications from a full-time
CAZ compared to a peak-time or a day-time CAZ
Daily charge How much would people / businesses have to
pay to enter the CAZ boundary where their
vehicle is affected and does not meet the CAZ
standards?
The level of charge is important as it catalyses
the users’ decision making and impacts the level
of benefits and costs of the CAZ
Enforcement and costs How will the CAZ standard be enforced within the
CAZ boundary e.g. manual or camera?
Depending on the location and the class of the
CAZ the enforcement options are different, but
they have implications on the potential cost and
the likely derived benefits

7. Potential CAZ areas being considered
A
(buses, coaches
and taxis)
Option 1A
Option 2A
Option 3A
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Geographical zone
1. Manchester city centre
2. Inside the M60
3. Segregated zones based on poor AQ

8. How do you define the boundary?
• To model a CAZ you need to define
a boundary – a line
• AQMA (red)?
• NO2 exceedance area in 2020?
• Political boundary?
• Saturn model boundary (e.g.
pink)?
• Buffer zone?
• Physical boundary – public
understanding?
• How do you reach consensus?
• GETAGREEMENT EARLY!
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9. Vehicle class and Euro standard
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• Note – various cities across Europe have LEZ’s which include combinations of
above, including cars (e.g. Germany, Lisbon)
Defra CAZ
class
Vehicles included
A Buses, coaches, taxis (Euro 6/VI)
B Buses, coaches, taxis and HGVs (Euro 6/VI)
C Buses, coaches, taxis, HGVs and LGVs (Euro 6/VI diesel
and Euro 4 petrol)
D Buses, coaches, taxis, HGVs, LGVs and cars (Euro 6/VI
diesel and Euro 4 petrol)

10. Air quality benefit area city centre & M60 (road rel)
Basic
modelling
only
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11. Emission benefit
Basic
modelling
only
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12. Screening Conclusions (WP1)
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• Class D outperforms other CAZ options for both
concentrations and emissions (as expected)
• Class A has more limited NOx improvement.
• Limited potential for improving PM10 – not just
related to emissions but brake and tyre wear
• NOx road emission and concentration road
contribution % reduction are broadly similar
(though this could vary at street level – fleet mix).
• Results for all 3 CAZ areas are broadly similar in
terms of % NOx road emissions reduction.

13. Air quality dependant on:
– Traffic flow data
– Fleet – e.g.. % of HDV
– Proportion of diesel
– Age of vehicles
– Estimated vs. real-world emissions?
• Primary NO2
• Test cycles
– NOx to NO2 conversion
– Other sources
How to refine AQ modelling (WP2)?

14. WP2 – Age and diesel proportions
• Worked with GMP,ANPR data from cameras on key routes into city
centre.
• Had to be anonymised
• Used neutral week
• 2.5 million records per year processed!
• Key parameters: fuel type, vehicle types, number plate (anonymised)
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15. Traffic flows, % splits and emissions
• Age/petrol/diesel per vehicle type rollover model – but is this really
true?
• Non-CAZ compliant vehicles replaced (ULEZ) with compliant
• Saturn used for various cost scenarios (£1 upwards) – at £5 became
cost sensitive - rerouting.
• Results used to calculate emissions – using appropriate Euro fleet
mixes.
• Emissions fed into dispersion model along with other sources and
results outputted for all scenarios.
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16. Dispersion modelling
• Primary NO2 and NOx emissions used
• Other sources used within ADMS-Urban and background
added
• NOx to NO2 conversion within ADMS used to calculated
NO2
http://www.gmtu.gov.uk/ga
m_maps/
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17. Conclusions
• Fleet mix and NO2?
– Defra NOx to NO2 assumes certain fleet mix proportions
– Sensitivity of pNO2
• Electric proportion - more brake & tyre wear?
• What are the timescales?
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Months 2 3 4 5 6 7 8 9 10 11 12
Agreeing areas
Screen
options
Agree
detailed
approach
ANPR -
fleet
Saturn
Emissions
Dispersion
Analysis & report

18. Thoughts
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• How can a CAZ be used to affect modal shift?
• How will a CAZ impact on vehicles outside the
CAZ?
• How will modal shift impact on health (e.g. more
active lifestyle & lower emissions)?
• How did we all get here today? – Will this change
in the future and what would make you change?

19. Questions?
hazel.peace@jacobs.com
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