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14 CLIMATE
GREENHOUSE GASES
14.1
LEGISLATIVE AND POLICY FRAMEWORK
14.1.1
The various legislative, policy and guidance documents used to shape the assessment of
Greenhouse Gases are outlined in
Table 14.1.
Table 14.1 – Legislative and Policy Framework
United Nations Framework Convention on Climate Change (UNFCCC) 283
LEGISLATION
The Climate Change Act (2008)
284
Infrastructure Carbon Review
285
National Planning Policy Framework
286
POLICY
National Policy Statement for National Networks
287
Environment Strategy for East Sussex
288
East Sussex Local Transport Plan 2011 - 2026
289
IAN 114/08 – Highways Agency Carbon Calculation and Reporting Requirements290
GUIDANCE
DMRB Volume 11 Section 3 HA 207/07 Air Quality291
IEMA EIA Guide to Assessing GHG Emissions and Evaluating their Significance292
283 United Nations Framework Convention on Climate Change https://unfccc.int/
284 HM Government Climate Change Act (2008) https://www.legislation.gov.uk/ukpga/2008/27/introduction
285 HM Treasury, Infrastructure Carbon Review (2013)
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/260710/infrastructure_c
arbon_review_251113.pdf
286 Ministry of Housing, Communities and Local Government National Planning Policy Framework (July
2018)https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/728643/Revised_
NPPF_2018.pdf
287 Department for Transport, National Policy Statement for National Networks (2014).
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/387222/npsnn-print.pdf
288 East Sussex Strategic Partnership, Environment Strategy for East Sussex (2011):
https://www.eastsussex.gov.uk/media/1988/environment_strategy_for_east_sussex.pdf
289 East Sussex County Council, Local Transport Plan –2011-2026 East Sussex Local Transport Plan 2011 – 2026 (2011)
https://www.eastsussex.gov.uk/media/2336/ltp3_main_doc_2011-2026.pdf
290 Highways Agency Interim Advice Note 114/08 Highways Agency Carbon Calculations and Reporting Requirements
(2008) http://www.standardsforhighways.co.uk/ha/standards/ians/pdfs/ian114.pdf
291 DMRB Volume 11 Section 3 HA 207/07 (2007)
http://www.standardsforhighways.co.uk/ha/standards/dmrb/vol11/Section3/ha20707.pdf
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TAG Unit A3 Environmental Impact Appraisal293
PAS 2080:2016 Carbon Management in Infrastructure294
14.1.2
Further detail on legislation and policy is provide in
Appendix 1.1.
14.2
ASSESSMENT METHODOLOGY
14.2.1
GHGs are natural and man-made gases occurring in the atmosphere which absorb and emit
infrared radiation thereby maintaining the Sun’s energy within the Earth’s atmosphere. There is a
scientific consensus that the major increase in the concentration of GHGs from man-made
sources is contributing to climate change.
14.2.2
The seven main GHGs defined by the Kyoto Protocol are carbon dioxide (CO2), methane (CH4),
nitrous oxide (N2O), hydrofluorocarbons, perfluorocarbons, sulphur hexafluoride and nitrogen
trifluoride. In combination, these GHG emissions are commonly expressed in terms of carbon
dioxide equivalents (CO2e) according to their relative global warming potential. For this reason,
the term ‘carbon’ may be used to refer to GHGs.
14.2.3
The assessment approach considers the likely magnitude of GHG emissions (or avoided
emissions) of the scheme in comparison to the baseline scenario with no scheme. It considers
emissions throughout the lifecycle of the scheme including:
Construction stage – for example the embodied emissions associated with materials,
transportation of materials to site and waste / arisings from site, and the construction process;
and
Operation - for example emissions (or avoided emissions) from end-user vehicles.
14.2.4
The decommissioning stage has not been assessed as the expected timescales for the scheme
reaching its end of life, are so far into the future that there is insufficient certainty about the
likelihood, type or scale of emissions activity to enable a meaningful assessment to be
undertaken. Lifecycle stages relevant to; maintenance; repair, replacement and refurbishment;
and emissions sources at end of life have been scoped out of this assessment due to the
negligible changes in emissions expected from these sources.
For the applicable construction and operation lifecycle stages of the scheme the assessment
includes the fol owing:
292 IEMA EIA guide to Assessing GHG emissions and evaluating their significance (2017) https://www.iema.net/policy/ghg-
in-eia-2017.pdf
293 Department for Transport Tag Unit A3 Environmental Impact Appraisal (2015)
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/638648/TAG_unit_a3_e
nvir_imp_app_dec_15.pdf
294 BSI PAS 2080:2016 Carbon management in infrastructure (2016)
https://shop.bsigroup.com/ProductDetail?pid=000000000030323493
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Col ection of available data / information on the scale of GHG emit ing activities for the
baseline scenario and for the scheme e.g. tonnes of concrete, litres of diesel, average daily
traffic flows. In each case, this covers the whole life cycle of the assets; and
Calculation of the GHG emissions using a standard emissions calculation methodology
applying a suitable emissions factor e.g. kgCO2e per tonne of concrete.
14.2.5
The construction stage emissions have been calculated using an industry recognised carbon
calculation tool. Highways England’s carbon tool295 has been used for this assessment. It
multiplies emissions activity (for example; quantities of material consumed, transport distances,
fuel and power) by the relevant emissions factors, expressed in carbon dioxide equivalents.
Values have been reported as tonnes of carbon dioxide equivalents (tCO2e). Professional
judgement has been applied when interpreting the bil of quantities for input into the Highways
England Carbon Calculation Tool. This was based upon knowledge of similar schemes.
14.2.6
The total operational stage end-user GHG emissions from traffic have been model ed as part of
the air quality assessment. The model ing includes the total GHG emissions for vehicles covering
the strategic and local road network in the area of the scheme and its surrounding region.
SIGNIFICANCE CRITERIA
14.2.7
IEMA guidance (IEMA’s EIA guide to Assessing GHG emissions and evaluating their
significance292) and professional judgement has been used to assess the significance of GHG
effects. In line with the National Networks NPS287, the GHG emissions arising from the scheme
are presented against the respective UK carbon budgets (see
Appendix 1.1) which have been
set by the UK government covering the period 2018 to 2032.
There are currently no agreed thresholds for what level of GHG emissions is considered
significant in EIA terms. Professional judgement is used regarding the likely magnitude of
emissions, the context of the Scheme and the potential impact on the Government meeting its
carbon reduction targets.
EFFECT SIGNIFICANCE
14.2.8
Professional judgement based on schemes of a similar size and nature wil be used to identify the
likely significance of effects. The fol owing terms have been used to define the significance of the
effects identified:
Major effect: where the Scheme could be expected to have a significant effect (either positive
or negative) on receptors;
Moderate effect: where the Scheme could be expected to have a noticeable effect (either
positive or negative) on receptors;
Minor effect: where the Scheme could be expected to result in a smal , barely noticeable
effect (either positive or negative) on receptors; and
295 Highways England Carbon emissions calculation tool https://www.gov.uk/government/publications/carbon-tool
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Negligible: where no discernible effect on receptors is expected due to the scheme.
14.3
ASSESSMENT ASSUMPTIONS AND LIMITATIONS
14.3.1
There is currently no specific guidance or carbon emissions threshold, which, if exceeded, would
be considered significant. The assessment wil therefore be based on professional judgement and
Highways England guidance.
14.3.2
This assessment has been completed based on the currently available information regarding the
scale and nature of the scheme. Type and quantities of material and waste provided by the
design team at this stage are indicative and wil be refined as the design of the scheme
progresses. Assumptions regarding the quantities have been made based on the current design
drawings, such as the thickness of asphalt and aggregates, quantity of concrete required for
culverts and catch pits, signage and lighting column dimensions.
14.3.3
The availability of robust information on the transportation of materials and waste to and from site
(the source of materials and destination of waste) has been taken from RICS296 transportation
scenarios in the absence of location specific data.
14.4
STUDY AREA
14.4.1
The greenhouse gas (GHG) assessment is not restricted by geographical area but instead
includes any increase or decrease in emissions as a result of the scheme, wherever that may be.
This includes:
Construction emissions in the area of the scheme footprint but also related to the transport of
materials to and from the site, their manufacturing and disposal (this may be far from the
scheme location (for example emissions for manufacture of concrete and steel).
Operational emissions (or reduction in emissions) which result from the end-use of the
scheme and any shifts in transport modes/patterns which may occur. Such emissions include
those for traffic using the scheme as wel as the surrounding regional road network.
14.5
BASELINE CONDITIONS
CURRENT EMISSIONS SOURCES AND FUTURE BASELINE
14.5.1
In the baseline (do nothing) scenario, GHG emissions occur constantly and widely as a result of
human and natural activity including energy consumption (fuel, power), industrial processes, land
use and land use change. The baseline GHG assessment considers the current emissions due to
the existing traffic in the study area, and the future baseline is the predicted increase in these
emissions sources without the scheme. The emissions generated during the baseline (do nothing)
and future baseline construction activities (repair or maintenance) is not assessed as data on the
manufacturing of materials and construction processes is not available.
296 RICS (2017) Whole life carbon assessment for the built environment. RICS professional standards and guidance, UK.
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14.5.2
Total end-user GHG emissions are presented in
Table 14.2 - Baseline GHG emissions data and
end user traffic in the region of the scheme for the baseline ‘do nothing’ scenario, and future
baseline year 2037. The baseline GHG emissions are expected to increase by 13% between
2023 (operational year) and 2041 (future year) as traffic growth outweighs increased vehicle
efficiency. The total end-user traffic emissions for the 60-year operational life of the scheme (2022
to 2081) are also presented along with the average annual emissions for that period.
Table 14.2 - Baseline GHG emissions data and end user traffic in the region of the scheme
TOTAL GHG EMISSIONS FOR ALL TRAFFIC IN THE TRAFFIC MODEL AREA
(THOUSAND TONNES OF CARBON DIOXIDE EQUIVALENT; KTCO2E)
SCENARIO
2022 (OPERATIONAL
2037 (FUTURE
AVERAGE PER YEAR
TOTAL
YEAR)
YEAR)
(2022-2081)
(2022-
2081)
BASELINE (‘DO
NOTHING’)
125.0
141.5
139.3
8357
14.5.3
In addition to the baseline traffic emissions presented above, emissions during 2016 within East
Sussex and national y297 are presented in
Table 14.3 - Greenhouse gas emissions, East Sussex
and National, 2016 for context.
Table 14.3 - Greenhouse gas emissions, East Sussex and National, 2016
SOURCE
EAST SUSSEX (KTCO2) NATIONAL (KTCO2)
A. Industry and Commercial Electricity
240
51,532
B. Industry and Commercial Gas
162
35,973
C. Large Industrial Instal ations
7.7
32,466
D. Industrial and Commercial Other Fuels
96
17,658
E. Agriculture
47
5,382
Industry and Commercial Total
552
143,010
F. Domestic Electricity
294
31,442
G. Domestic Gas
490
60,203
H. Domestic 'Other Fuels'
101
10,788
297 Department for Business, Energy & Industrial Strategy (2018), UK local authority and regional carbon dioxide emissions
national statistics: 2005 to 2016, https://www.gov.uk/government/statistics/uk-local-authority-and-regional-carbon-dioxide-
emissions-national-statistics-2005-2016
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Domestic Total
884
102,432
I. Road Transport (A roads)
460
54,351
J. Road Transport (Motorways)
-
28,032
K. Road Transport (Minor roads)
438
41,483
L. Diesel Railways
17
2,151
M. Transport Other
5
2,036
Transport Total
919.5
128,053
N. LULUCF Net Emissions
-268
-16,026
Grand Total
2088
357,470
Population ('000s, mid-year estimate)
545
65,648
Per Capita Emissions (t)
4
5
14.6
POTENTIAL IMPACTS
14.6.1
The impacts of GHGs relate to their contribution to climate change. These impacts are global and
cumulative in nature, with every tonne of GHGs contributing to impacts on natural and human
systems. GHG emissions result in the same global effects wherever and whenever they occur
and, therefore, the sensitivity of different human and natural receptors is not considered.
CONSTRUCTION PHASE GHG EMISSIONS
14.6.2
The scheme has the potential to result in increases in greenhouse gas emissions associated with
construction activities (such as manufacturing of materials and construction processes). During
construction, notable sources of emissions wil include ‘embedded carbon’ emissions generated
during extraction and manufacturing of construction materials including: asphalt, aggregate,
structural and reinforced steel and concrete. These are required for: the pavement for junction
improvements; development of the Shared Use Path; construction of the new bridge over the
Cuckmere River; and widening of the existing bridge over the railway at Polegate.
14.6.3
The construction lifecycle stages included within the scope of this EAR and corresponding
potential sources of emissions are outlined in
Table 14.4.
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Table 14.4 - Key emissions activity during the scheme lifespan
CONSTRUCTION
POTENTIAL SOURCES OF EMISSIONS (NOT EXHAUSTIVE)
LIFECYCLE STAGE
Embodied emissions associated with extraction and manufacturing of the required
raw materials, including:
33,820 tonnes asphalt for surfacing the Shared Use Path and junction
improvements
Product stage
13,499 tonnes aggregate for structural backfil and drainage
(manufacture and
13.474 tonnes of imported earthworks (fil )
transport of raw materials
to suppliers)
2,462 tonnes concrete for the bridge structures and retaining wal s, drainage
feature and lighting and signage foundations.
76 tonnes steel for bridge structures, reinforcement and retaining wal s.
Smal er quantities of ancil ary aspects such plastic drainage pipes, aluminium
signage and lighting columns, copper cabling and timber for fencing and
formwork.
Emissions from the construction stage include such emissions sources as
fuel/energy consumption from:
Construction process
Delivery of materials for junction improvement, new Shared Use Path and
stage (transport of
bridge, widening of existing bridge at Polegate as wel as fil material
materials and arisings
to/from site; construction Export and disposal of 19,699 tonnes carriageway planings
process, earth
Export and disposal of 5,438 tonnes of surplus topsoil
movements)
Export and disposal of 639 tonnes concrete
Export and disposal of smal er quantities of arisings such as mixed metals
and timber.
14.6.4
The total construction related GHG emissions arising from: material supply; the manufacturing of
materials; waste generation and disposal; and transportation of materials and waste to and from
site; has been calculated to be 17.4 thousand tonnes of carbon dioxide equivalent (KTCO2e), as
presented in
Figure 14.1.
14.6.5
Figure 14.1 also shows a breakdown of the GHG emissions ‘hot spots’ from materials, as the
main source of emissions from construction of the scheme.
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Figure 14.1 Total GHG Emissions Breakdowns Associated with Materials
14.6.6
The majority (93.5%) of GHG emissions are associated with materials (product stage ‘cradle to
gate’ or ‘embodied’ emissions) with 4.1% from transport of those materials and wastes and 2.4%
from waste generation and disposal.
14.6.7
The majority (89.4%) of the emissions for materials relate to the pavement for the junction
improvements and bridge widening. Other significant contributions are from bulk materials (5.7%)
required for the scheme which comprise aggregate and concrete required for al aspects of the
scheme and asphalt for the Shared Use Path. Smal er contributions are from street furniture
(lighting and signage, 2.2%), drainage (1.6%), civil structures (steelwork and formwork only,
concrete is accounted for in bulk materials, 0.7%) and less than 1% from earthworks and fencing.
14.6.8
In the absence of agreed thresholds for what level of GHG emissions is considered significant in
an EIA, professional judgement, based on schemes of a similar size and nature, and presenting
the scheme GHG emissions against the respective UK carbon budgets and total road CO2
emissions for East Sussex has been used to assess the significance of effects.
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14.6.9
The GHG emissions from the construction of the scheme is likely to have an adverse impact. The
magnitude of change in GHG emissions is considered to be
negligible.
14.6.10
The scheme is therefore expected to have an effect of
neutral significance on climate, during
construction. This assessment takes into consideration the confirmed construction phase
mitigation measures, the magnitude of GHG emissions and the context of the scheme, and using
professional judgement it is considered that the neutral effect of this scheme wil not be
significant. Furthermore, as presented in
Table 14.6 - Key emissions activity during the scheme
lifespan, the GHG impacts of the scheme would not have a material impact on the Government
meeting its carbon reduction targets.
OPERATIONAL GHG EMISSIONS
14.6.11
The scheme wil result in changes to end-user traffic emissions throughout its operational life,
which could be an increase or decrease depending on the effect on traffic flows, percentage of
Heavy Duty Vehicles (%HDV) and speed. Any increase in emissions and the corresponding
concentrations of GHGs present in the atmosphere wil contribute to global warming and climate
change.
14.6.12
Total end user emissions are presented in
Table 14.5 for the year 2022 (the first year of operation
for the scheme) and the year 2037 (the future model ed year). In addition, the average annual and
total emissions for the 60 year assumed operational period of 2022 to 2081 are presented. The
baseline figures (without the scheme) are included to show the impact due to the scheme.
Table 14.5 - End user GHG emission data for traffic in the region of the scheme
TOTAL GHG EMISSIONS FOR ALL TRAFFIC IN THE TRAFFIC MODEL AREA
(THOUSAND TONNES OF CARBON DIOXIDE EQUIVALENT; KTCO2E)
SCENARIO
2022
(OPERATIONAL
2037 (FUTURE
AVERAGE PER
TOTAL
YEAR)
YEAR)
YEAR (2022-2081)
(2022-2081)
BASELINE (‘DO
NOTHING’)
125.0
141.5
139.3
8357
THE SCHEME
125.5
141.7
139.5
8372
14.6.13
The total regional traffic emissions for the operational lifespan of the scheme (2022-2081) are
14 tCO2e higher (+0.2%) than the baseline (do nothing) scenario.
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14.6.14
The magnitude of change in GHG emissions during operation is predicted to be
negligible. GHG
emissions from the operation of the scheme are likely to have an effect of
neutral significance.
this assessment take into consideration the magnitude of GHG emissions (slight increase) and
the context of the scheme, using professional judgement including previous experience of road
infrastructure schemes, it is considered that the neutral effect of this scheme wil not be
significant. Furthermore, as presented in
Table 14.6 - Key emissions activity during the scheme
lifespan, the GHG impacts of the scheme would not have a material impact on the Government
meeting its carbon reduction targets.
SCHEME IMPACT ON UK CARBON BUDGETS AND EAST SUSSEX 2016 ROAD
EMISSIONS
14.6.15
The total estimated GHG emissions arising from the scheme have been estimated as part of the
air quality assessment, and are presented in
Table 14.6 below. They are presented for the
construction stage to first year of operation (2020-2022), the operation stage (2022-2081) and the
overal total for the whole lifecycle (2020-2081).
14.6.16
The total emissions during each of the UK National Carbon Budget periods is presented and
compared in percentage terms to the respective National budget. The Third Carbon Budget
covering 2018 to 2022 is 2,544 mil ion tCO2e. The Fourth Carbon Budget covering 2023 to 2027
is 1,950 mil ion tCO2e. The Fifth Carbon Budget covering 2028 to 2032 is 1,725 mil ion tCO2e
(the latest carbon budget agreed by the government).
14.6.17
The percentage of 1 year’s operational phase total GHG emissions arising from the scheme are
also presented in comparison with the 2016 road CO2 emissions for East Sussex in 2016297.
Table 14.6 - Key emissions activity during the scheme lifespan
TOTAL GREENHOUSE GAS
STAGE / TIMING
EMISSIONS (THOUSAND TONNES OF
CARBON DIOXIDE EQUIVALENT;
kTCO2e)
Construction phase (2020-2022)
17.4
Operational phase (2022 – 2081)
14.5 (0.2 per year)
Total for lifecycle (2020 – 2081)
31.9
Total for third carbon Budget period (2018 – 2022) [% of budget]
17.9 [0.00070%]
Total for fourth carbon Budget period (2023 – 2027) [% of budget]
2.2 [0.00011%]
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Total for fifth carbon Budget period (2028 – 2032) [% of budget]
1.7 [0.00010%]
East Sussex Total Road Co2 emissions estimates 2016 [% of 1
460 [0.0525%]
year’s operational phase]
Table 14.7 - Summary of GHG Effects
LONG TERM/
MEDIUM
SIGNIFICANCE
EFFECT
RECEPTOR
BENEFICIAL/ DIRECT/
SHORT TERM/
ADVERSE
INDIRECT
(VERY LARGE
TEMPORARY
– NEUTRAL)
/PERMANENT
CONSTRUCTION
GHG emissions
result in the
same global
INCREASE IN GHG effects wherever
EMISSIONS FROM and whenever
MANUFACTURE
they occur and,
Long term
AND SUPPLY OF therefore, the Adverse
Direct
Neutral
MATERIALS AND sensitivity of
Permanent
CONSTRUCTION
dif erent human
ACTIVITIES
and natural
receptors is not
considered
OPERATION
GHG emissions
result in the
same global
CHANGE GHG
effects wherever
EMISSIONS FROM and whenever
Long term
END-USER
they occur and, Adverse
Direct
Neutral
EMISSIONS
therefore, the
Permanent
(REGIONAL
sensitivity of
TRAFFIC FLOWS) dif erent human
and natural
receptors is not
considered
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14.7
DESIGN, MITIGATION AND ENHANCEMENT MEASURES
CONSTRUCTION PHASE
14.7.1
The confirmed mitigation measures to reduce the impact of GHG emissions during construction
comprise; the use of site won arisings (earthworks and topsoil), local sourcing of materials and
waste management facilities, and the use of materials containing recycled content (for example
aggregate, asphalt and cement binder).
14.7.1
A summary of further measures for consideration are noted in
Table 14.8 - Recommended
design, mitigation or enhancement measures.
Table 14.8 - Recommended design, mitigation or enhancement measures
MECHANISM/
MEASURE
DESCRIPTION
RESPONSIBILITY
TIMING
Design optimisation to reflect the carbon reduction
Detailed
hierarchy.
design
Detailed designer
Reduce the elements required for the scheme.
Detailed
design
Detailed designer
Reduce the requirement for construction materials
Detailed
Detailed designer
Reduce
through design and use of site won arisings;
design and
and Lead
embodied
Construction Contractor
carbon through
finessing the
detailed design Substitute construction elements for lower-carbon
Detailed
Detailed designer
alternatives (e.g. changing the design and materials design and
and Lead
for the bridge).
Construction Contractor
Specify materials and products with reduced
embodied GHG emissions including through material Detailed
Detailed designer
substitution, recycled or secondary content and from design and
and Lead
renewable source.
Construction Contractor
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Maximise opportunities for local sourcing of materials
and use of local waste management facilities.
Construction Lead Contractor
Select and engage with material suppliers and
construction contractors taking into account their
Detailed
Detailed designer
EMBODIED
policies and commitments to reduction of GHG
design and
and Lead
CARBON
emissions, including embodied emission in materials. Construction Contractor
THROUGH
CONSTRUCTION
PHASE
Minimise energy consumption including fuel usage by,
EFFICIENCIES for example, reducing the requirement for earth
Construction Lead Contractor
movements to/from and within the construction site.
Use energy-efficient plant; minimising vehicle idling;
and use renewable energy devices wherever possible. Construction Lead Contractor
Designing, specifying and constructing the scheme
with a view to maximising the operational lifespan and Detailed
minimising the need for maintenance and
design
Detailed designer
refurbishment (and al associated emissions).
Designing, specifying and constructing the scheme
with a view to maximising the potential for reuse and Detailed
recycling of materials/elements at the end-of-life
design
Detailed designer
CHANGE GHG stage.
EMISSIONS
FROM END-
USER
Specifying high ef iciency mechanical and electrical
Detailed
EMISSIONS
equipment such as lighting and telecoms.
design
Detailed designer
(REGIONAL
TRAFFIC
FLOWS)
Operating, maintaining and refurbishing the scheme
using best-practice efficient approaches and
equipment. Ensure designs are focussed upon
reduction of emissions from end-user vehicle
movement (traffic) for example by providing the
Detailed
conditions for efficient low-carbon vehicles and driving design
Detailed designer
practices, such as increasing capacity, which would
potential y result in a reduction in emission per vehicle
where congestion is relieved.
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14.8
ASSESSMENT OF LIKELY SIGNIFICANT EFFECTS
Table 14.9 - Summary of effects
ASSESSMENT OF EFFECT
MITIGATION
RESIDUAL EFFECT
Long term/
EFFECT
RECEPTOR
medium
Beneficial/ Direct/ short term/ Significance
Adverse
Indirect
(Very large
Description
Mechanism/
Timing
Responsibility Beneficial/
Adverse Significance
Temporary – neutral)
/Permanent
Construction Phase
Design optimisation to
minimise material usage,
recover site arisings,
minimise waste generation
and maximising efficient
Increase in
construction and
GHG
transportation methods
emissions
from
Global
manufacture receptors
Long term
Specifying materials and
During Design Designer and
and supply sensitive to Adverse
Direct
Neutral
products with reduced
and
Contractor
Adverse Neutral
of materials climate
Permanent
embodied GHG emissions construction
and
change
construction
Selection of material
activities
suppliers and construction
contractors commit ed to
reducing GHG emissions.
Use of ef icient construction
plant and equipment.
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Operational Phase
Change
Global
GHG
receptors
Design optimisation to
emissions
sensitive to
maximise operational
from end-
climate
Long term
efficiency;
During
user
change
Adverse
Direct
Neutral
Focus design on reduction operation
Designer
Adverse Neutral
emissions
Permanent
of emissions from end-user
(regional
vehicle movements.
traffic flows)
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CLIMATE RESILIENCE
14.9
INTRODUCTION
14.9.1
The requirement to consider a scheme’s vulnerability to climate change results from the 2014
amendment to the EIA Directive (2014/52). The Directive has been ful y transposed into UK
law in The Environmental Impact Assessment (Miscel aneous Amendments Relating to
Harbours, Highways and Transport) Regulations 2017 and came into force in the UK on the
2017. The Directive requires:
“A description of the likely significant effects of the project on climate (for example the nature
and magnitude of greenhouse gas emissions) and the vulnerability of the project to climate
change.”
14.9.2
This section assesses the vulnerability of the scheme to the impacts of climate change.
14.10
SCHEME
14.10.1
The scheme consists of the elements outlined in
Chapter 2 – The Project.:
14.11
STUDY AREA
14.11.1
The assessment of vulnerability of the scheme to the impacts of climate change has been
informed by regional scale information on historic and projected change in climate variables.
The UK Climate Projections 2018 (UKCP18)298 are the most up-to-date projections of climate
change for the UK, however, data from the probabilistic projections at the administrative
region scale were not available. Information on the projected climate has therefore been
taken from previous projections, UKCP09299, for the South-East England administrative area.
The vulnerability of scheme elements within the scheme extent to changes in climate (at the
regional scale) has been assessed.
14.12
ASSESSMENT APPROACH
14.12.1
This section outlines the approach to assessment of climate vulnerability and risk. This
approach aligns with the fol owing UK and international guidance:
IEMA (2015) Environmental Impact Assessment Guide to Climate Change Resilience
and Adaptation300
European Commission (2013) Guidance on Integrating Climate Change and Biodiversity
into Environmental Impact Assessment301;
298 United Kingdom Climate Projections 2018 https://ukclimateprojections-ui.metoffice.gov.uk/
299 United Kingdom Climate Projections 2009 http://ukclimateprojections.metoffice.gov.uk/
300 IEMA (2015) Environmental Impact Assessment Guide to Climate Change Resilience and Adaptation. Available
at:
https://www.iema.net/assets/templates/documents/iema_guidance_documents_eia_climate_change_resilience_and_
adaptation%20(1).pdf.
301 European Commission (2013) Guidance on Integrating Climate Change and Biodiversity into Environmental
Impact Assessment. http://ec.europa.eu/environment/eia/pdf/EIA%20Guidance.pdf
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European Commission (2016) Climate change and major projects302; and
European Commission Non-paper Guidelines for Project Managers: Making vulnerable
investments climate resilient303.
14.12.2
The ful approach consists of 4 steps:
Step 1: Identify receptors and analyse policy context;
Step 2: Climate vulnerability assessment;
Step 3: Risk assessment; and
Step 4: Adaptation measures.
14.12.3
The PCF Stage 3 Scoping Report (July 2018) presented the detailed assessment and results
of Step 1 and Step 2 describing the level of vulnerability of the scheme to the impacts of
climate change, and determining which vulnerabilities should be assessed further (Steps 3
and 4). This vulnerability assessment is presented in
Appendix 14.1. This EAR completes
the assessment Steps 3 and 4.
STEP 1: IDENTIFY RECEPTORS AND ANALYSE POLICY CONTEXT
14.12.4
During this stage, relevant receptors which may be affected by climate change were identified
with consideration given to the impact of extreme weather and changes in climate on the
scheme over its lifetime. This stage includes a definition of the policy context.
STEP 2: CLIMATE VULNERABILITY ASSESSMENT
14.12.5
This stage comprised an assessment of the vulnerability of the receptors identified in Step 1
to projected climate change and extreme weather variables. The vulnerability of a receptor to
extreme weather and climate change is a function of:
The typical sensitivity of the receptor to climate variables – based on literature review and
expert judgement.
The exposure of the receptor to projected change in climate variables – based on
information on observed climate and projected climate.
14.12.6
For each element of the vulnerability assessment (sensitivity and exposure), a categorisation
is assigned to each climate variable based on the fol owing scale:
High: High climate sensitivity or exposure.
Moderate: Moderate climate sensitivity or exposure.
Low: No significant climate sensitivity or exposure.
14.12.7
This is a qualitative assessment informed by expert opinion and supporting literature.
302 European Commission (2016) Climate Change and Major Projects. :
https://ec.europa.eu/clima/sites/clima/files/docs/major_projects_en.pdf
303 European Commission (undated) Non-paper Guidelines for Project Managers: Making vulnerable investments
climate resilient. Available at: http://climate-adapt.eea.europa.eu/metadata/guidances/non-paper-guidelines-for-
project-managers-making-vulnerable-investments-climate-resilient/guidelines-for-project-managers.pdf
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14.12.8
The vulnerability of receptors to climate variables was determined from the combination of the
sensitivity and exposure categorisation, using the matrix shown in
Table 14.11. At this point,
climate variables to which the scheme’s vulnerability has been assessed as ‘Low’ were
scoped out of further assessment. Climate variables to which the scheme’s vulnerability has
been assessed as ‘High’ or ‘Medium’ were taken forward to Steps 3 and 4.
TABLE 14.10 - VULNERABILITY MATRIX
EXPOSURE
SENSITIVITY
LOW
MODERATE
HIGH
Low
Low vulnerability
Low vulnerability
Low vulnerability
Moderate
Low vulnerability
Medium vulnerability
Medium vulnerability
High
Low vulnerability
Medium vulnerability
High vulnerability
STEP 3: RISK ASSESSMENT
14.12.9
Impacts related to the ‘scoped in’ variables were identified. Typical impacts are shown in
Table 14.12.
TABLE 14.11 - TYPICAL HAZARDS ASSOCIATED WITH CLIMATE VARIABLES
CLIMATE VARIABLE
CLIMATE-RELATED IMPACTS
High temperatures, longer growing season
Average air temperature change (annual,
seasonal, monthly)
Fewer incidences of low temperature related hazards such as
ice, snow, damage from freeze-thaw
Extreme air temperature (frequency and
magnitude)
Heatwaves
Average precipitation (annual, seasonal,
Flooding (fluvial, pluvial), reduced ground stability
monthly)
Soil moisture deficit, snow, ice and hail
Extreme rainfal (frequency and magnitude) Flooding (fluvial, pluvial), reduced ground stability
Average wind speed change (annual,
seasonal, monthly)
Increase wind loading
Gales and extreme winds (frequency and
magnitude)
Increase in storm intensity, storm surge, lightning
Humidity
Fog
Solar radiation
High UV levels
Sea level
Coastal flooding, coastal erosion
14.12.10
The risk assessment is undertaken by considering the likelihood of climate hazards occurring
and the consequence to the scheme elements if they occur.
14.12.11
Likelihood and consequence are qualitatively assessed using the descriptions in
Table 14.13
and
Table 14.14.
TABLE 14.12 – QUALITATIVE DESCRIPTION OF CONSEQUENCE
CONSEQUENCE OF
IMPACT
DESCRIPTION
Negligible
Disruption to an isolated section of a strategic route lasting less than 1 day.
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Minor adverse
Regional level disruption to strategic route(s) lasting less than 1 day.
Moderate adverse
Regional level disruption to strategic route(s) lasting more than 1 day but less than 1
week.
Large adverse
National level disruption1 to strategic route(s) lasting more than 1 day but less than 1
week OR regional level disruption to strategic route(s) lasting more than 1 week.
Very large adverse
National level (or greater) disruption to strategic route(s) lasting more than 1 week.
TABLE 14.13 – QUALITATIVE DESCRIPTION OF LIKELIHOOD
LIKELIHOOD OF
DESCRIPTION
IMPACT
Very low
The event may occur once during the lifetime of the scheme (60 years).
Low
The event occurs during the lifetime of the scheme (60 years) e.g. once in 60 years.
Medium
The event occurs limited times during the lifetime of the scheme (60 years) e.g.
approximately once every 15 years, typical y 4 events.
High
The event occurs several times during the lifetime of the scheme (60 years) e.g.
approximately once every five years, typical y 12 events;
Very high
The event occurs multiple times during the lifetime of the scheme (60 years) e.g.
approximately annual y, typical y 60 events.
14.12.12
These determinants are then combined to develop a climate risk rating for each scheme
element in respect to specific climate hazards (
Table 14.15). The assessment is a qualitative
assessment based on expert judgment, engagement with the design team and a review of
relevant literature.
TABLE 14.14 - SIGNIFICANCE RATING MATRIX
LIKELIHOOD OF
CONSEQUENCE OF IMPACT OCCURRING
IMPACT
VERY LARGE
OCCURRING
NEGLIGIBLE
MINOR ADVERSE MODERATE
LARGE ADVERSE
ADVERSE
ADVERSE
Very low
Not significant
Not significant
Not significant
Not significant
Not significant
Low
Not significant
Not significant
Not significant
Significant
Significant
Medium
Not significant
Not significant
Significant
Significant
Significant
High
Not significant
Significant
Significant
Significant
Significant
Very high
Not significant
Significant
Significant
Significant
Significant
STEP 4: MITIGATION MEASURES
14.12.13
Mitigation measures for the significant risks are identified through consultation with the design
team and based on expert opinion. Taking account of the contribution of incorporated
mitigation measures, a summary of the level of climate resilience of the scheme elements to
climate change is applied:
Low - a low level of climate resilience leading to
significant residual climate risk.
Remedial action or adaptation is required as a priority.
Moderate – a moderate degree of climate resilience leading to
no significant residual
climate risk. However, ongoing monitoring and/or remedial action or adaptation could be
considered; and
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High – a strong degree of climate resilience leading to
no significant residual climate risk.
Remedial action or adaptation may be required but is not a priority.
14.12.14
Recommendations for supplementary climate change adaptation measures are then
identified where necessary.
14.13
ASSESSMENT OF EFFECTS
ASSESSMENT ASSUMPTIONS AND LIMITATIONS
14.13.1
In the absence of an agreed methodology for assessing the vulnerability of schemes to
climate change, the approach in this chapter has been developed and applied based on
existing best practice, and in col aboration with Highways England and expert opinion.
14.13.2
The UK Climate Projections 2018 (UKCP18) are the most up-to-date projections of climate
change for the UK. However, at the time of writing this EAR chapter, UKCP18 regional data
was not available, so UKCP09 regional data was used.
14.13.3
As future emissions of GHGs, and resulting pathway, is uncertain. A precautionary approach
has been applied, by selecting the High emissions scenario and long-term timeslice304
(2080s), in line with Highways England guidance. This time horizon is consistent with the 60
years design life of the scheme.
14.13.4
The determination of resilience has been undertaken under the assumption that robust
design standards wil be adhered to where detailed information is unavailable.
STEP 1 AND STEP 2: IDENTIFICATION OF RECEPTORS AND VULNERABILITY
ASSESSMENT FINDINGS
14.13.5
Steps 1 and 2 were completed in the PCF Stage 3 Scoping Report (July 2018).
Appendix
14.1 presents the findings of Step 2, the Vulnerability Assessment. The climate variables to
which the scheme’s vulnerability has been assessed as ‘High’ or ‘Medium’ were taken
forward to Steps 3 and 4 and are present in
Table 14.15,
Table 14.16 and
Table 14.17.
TABLE 14.15 - VULNERABILITY ASSESSMENT - ROAD
CLIMATE VARIABLE
SENSITIVITY
EXPOSURE
VULNERABILITY
RATING
RATING
RATING
Extreme rainfal
Medium
Medium
Medium
vulnerability
Precipitation
Drought
Medium
High
Medium
vulnerability
Temperature
Extreme temperature
Medium
High
Medium
vulnerability
304 UKCP09 projections are given for seven overlapping 30-year time periods (timeslice).
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Wind
Gales and extreme wind
events
Medium
Medium
Medium
vulnerability
Soil moisture
Medium
High
Medium
vulnerability
Soil
Stability
Medium
Medium
Medium
vulnerability
TABLE 14.16 - VULNERABILITY ASSESSMENT – BRIDGE
CLIMATE VARIABLE
SENSITIVITY
EXPOSURE
VULNERABILITY
RATING
RATING
RATING
Precipitation
Extreme rainfal
Medium
Medium
Medium
vulnerability
Temperature
Extreme temperature
Medium
Medium
Medium
vulnerability
Wind
Gales and extreme wind
events
High
Medium
Medium
vulnerability
Soil
Stability
Medium
Medium
Medium
vulnerability
TABLE 14.17 - VULNERABILITY ASSESSMENT – CYCLE AND FOOTWAY
CLIMATE VARIABLE
SENSITIVITY
EXPOSURE
VULNERABILITY
RATING
RATING
RATING
Extreme rainfal
Medium
Medium
Medium
Precipitation
vulnerability
Drought
Medium
High
Medium
vulnerability
Temperature
Extreme temperature
Medium
High
Medium
vulnerability
Wind
Gales and extreme wind
events
Medium
Medium
Medium
vulnerability
Soil moisture
Medium
High
Medium
vulnerability
Soil
Stability
Medium
Medium
Medium
vulnerability
STEP 3: RISK ASSESSMENT
14.13.6
This section describes the assessment of risk based on the medium vulnerability climate
variables identified in Step 2. No high vulnerability variables were identified.
14.13.7
Climate and weather-related impacts associated with the identified medium vulnerabilities
during construction and operation are described in
Appendix 14.2. Unless stated otherwise,
the impacts identified in
Appendix 14.2 are expected to impact the whole scheme.
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14.13.8
Table 14.19 presents significance ratings for each of the identified climate risks, across both
the construction and operational phases, to the scheme based on a qualitative assessment of
likelihood and consequence.
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TABLE 14.18 – SIGNIFICANT RISKS IDENTIFIED FOR THE SCHEME (PRE MITIGATION)
DESCRIPTION OF RISK
SIGNIFICANCE
MITIGATABLE
COMPONENT
CONSEQUENCE LIKELIHOOD
RATING (WITHOUT THROUGH DMRB/
HAZARD
RISK
MITIGATION)
DESIGN
STANDARDS?
Damage to carriageway
structures due to
Moderate
increased runoff
adverse
Medium
Significant
Yes
Medium. Areas of the Scheme
Soil saturation and water
are located within Flood Zone 2
damage
Minor adverse
or 3 although risk could change Not Significant
N/A
over time due to climate
change.
Undercutting and scour
Extreme rainfal
particularly in relation to
Moderate
the bridge over the
adverse
Medium
Significant
Yes
Cuckmere River
Increased slope instability Moderate
adverse
Medium
Significant
Yes
Structural stability
Damage to unpaved
shoulders
Minor adverse
Medium
Not Significant
N/A
Erosion, silting and
sedimentation
Minor adverse
Medium
Not Significant
N/A
Drought
Loss of vegetation leading
to greater erosion risk
Minor adverse
Medium
Not Significant
N/A
Cracking and expansion
particularly impacting
Moderate
bridge structures
adverse
Medium
Significant
Yes
Extreme
Overheating of equipment,
temperature
including during
Moderate
construction and operation adverse
Medium
Significant
Yes
(e.g. electronic signage)
Increased risk of erosion Minor adverse
Medium
Not Significant
N/A
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Risk of damage to
structures and
Moderate
foundations, including
adverse
Medium
Significant
Yes
Gales and extreme flood scour and/or runof
wind events
Damage to signage and
site structures
Minor adverse
Medium
Not Significant
N/A
Erosion of banks and
exposed surfaces
Minor adverse
Medium
Not Significant
N/A
Shrinking and cracking of Moderate
soils leading to subsidence adverse
Medium
Significant
Yes
Soil softening and erosion
leading to col apse and
Moderate
settlement of soil
adverse
Medium
Significant
Yes
Soil moisture
structures
Increased slope instability Moderate
adverse
Medium
Significant
Yes
Soil saturation
Moderate
adverse
Medium
Significant
Yes
Subsidence impacting
road, cycleway and
Moderate
footpath and bridges over adverse
Medium
Significant
Yes
the Cuckmere River
Failure of earthworks due Moderate
Stability
to desiccation
adverse
Medium
Significant
Yes
Shrinking and cracking of Moderate
soils
adverse
Medium
Significant
Yes
Greater rates of soil
erosion
Minor adverse
Medium
Not Significant
N/A
Drying out of construction
materials and cracking
Minor adverse
Medium
Not Significant
N/A
Drought
Structural
Deformation of rigid
Moderate
robustness
structures
adverse
Low
Not Significant
N/A
Extreme
Risks to stored equipment,
temperature
including waste
Minor adverse
Medium
Not Significant
N/A
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Damage and disruption
(e.g. fires)
Minor adverse
Medium
Not Significant
N/A
Drains and culverts
becoming overwhelmed
Minor adverse
High
Significant
Yes
Blockages of drainage
Extreme rainfal
assets
Minor adverse
High
Significant
Yes
Greater mobilisation of
pol utants in soil/ground
causing premature
Minor adverse
Medium
Not Significant
N/A
deterioration of materials
Drought
Damage and disruption
(fires)
Minor adverse
Medium
Not Significant
N/A
Damage to external
weather proofing and
Minor adverse
Medium
Not Significant
N/A
Extreme
detailing at ground level
Ancil ary
temperature
Higher day and night-time
equipment
temperatures
Minor adverse
High
Significant
Yes
Gales and extreme Damage from high winds
wind events
and rain-infiltration into
Minor adverse
Medium
Not Significant
N/A
surfaces and materials
Shrinking and cracking of Moderate
soils leading to subsidence adverse
Medium
Significant
Yes
Soil moisture
Soil softening and erosion
leading to col apse and
Moderate
settlement of soil
adverse
Medium
Significant
Yes
structures
Increased rate of
Stability
deterioration, potential y
leading to need for early Minor adverse
Medium
Not Significant
N/A
replacement
Softening of subsurface
Material durability Extreme rainfal
materials below the road, Moderate
cycle and footway and
adverse
Medium
Significant
Yes
bridge structures
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Enhanced reactions when
cement stabilising and
Minor adverse
Medium
Not Significant
N/A
Drought and
drying of concrete
prolonged dry spel s, Increased rate of
including drier
deterioration of materials,
summers
potential y leading to need Minor adverse
Medium
Not Significant
N/A
for early replacement
Shrinking and cracking
Minor adverse
Medium
Not Significant
N/A
Enhanced reactions when
Extreme
cement is stabilising and Minor adverse
Medium
Not Significant
N/A
temperatures,
drying of concrete
including hot er
UV degradation of
summers
exposed equipment e.g.
Minor adverse
Medium
Not Significant
N/A
cabling
Increased rate of
Gales and extreme deterioration of materials, Moderate
wind events
potential y leading to early adverse
Medium
Significant
Yes
replacement
Greater mobilisation of
Soil moisture
pol utants in the
Minor adverse
Medium
Not Significant
N/A
soil/ground
Increased rate of
Stability
deterioration of materials,
potential y leading to need Minor adverse
Medium
Not Significant
N/A
for early replacement
Water accumulation
causing disruption to
Moderate
construction and operation adverse
Medium
Significant
Yes
Site contents and
Stopping of services due Moderate
business
Extreme rainfal
to asset failure
adverse
Medium
Significant
Yes
continuity
Scour of embankments
leading to increased
Moderate
maintenance
adverse
Medium
Significant
Yes
Traf ic disruption and
Moderate
Medium
Significant
Yes
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congestion
adverse
Excessive vegetation
growth
Minor adverse
Medium
Not Significant
N/A
Reduced opportunities for
maintenance
Minor adverse
Medium
Not Significant
N/A
Reduced working periods
and delays
Minor adverse
Medium
Not Significant
N/A
Extreme
Reduced opportunities for
temperature
maintenance
Minor adverse
Medium
Not Significant
N/A
Operational disruption
Moderate
adverse
Medium
Significant
Yes
Increased maintenance
Soil moisture
costs and risks to
Moderate
operation
adverse
Low
Not Significant
N/A
Increased maintenance
Stability
costs and risks to
Moderate
operation
adverse
Low
Not Significant
N/A
Dif icult working conditions Minor adverse
High
Significant
Yes
Movement of debris
Moderate
Extreme rainfal
causing slip, trip and fal
hazards
adverse
Medium
Significant
Yes
Health and safety risks to Moderate
road users
adverse
Medium
Significant
Yes
H&S of users
Drought, including More dust
Minor adverse
Medium
Not Significant
N/A
(operators and
long periods of dry Evaporation of
customers)
weather
construction water
Minor adverse
Medium
Not Significant
N/A
Dif icult working conditions Minor adverse
High
Significant
Yes
Increased fire risk
Moderate
Extreme
adverse
Medium
Significant
Yes
temperature
Hot surfaces may cause
injury
Minor
Medium
Not Significant
N/A
Health and safety risks to Minor adverse
Medium
Not Significant
N/A
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road users
Dif icult working conditions Minor adverse
High
Significant
Yes
Gales and extreme Health and safety risks to
wind events
road users particularly high Moderate
sided vehicles)
adverse
Medium
Significant
Yes
Soil moisture
Dif icult working conditions Minor adverse Medium
Not Significant
N/A
Movement of debris
Stability
causing slip, trip and fal Minor adverse Medium
Not Significant
N/A
hazards
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14.13.9
Risks which have been assessed as not significant are not considered further in this
assessment although ongoing maintenance of the asset by the Applicant in its capacity as
highways authority for the scheme wil be upheld to ensure that these risks are addressed in
the future if their risk status changes and/or new information might affect their risk status.
STEP 4: MITIGATION MEASURES
14.13.10
This section outlines the adaptation measures that have been integrated into the Scheme in
response to significant risks.
14.13.11
In consultation with the design and project teams, a range of mitigation options have been
identified to reduce the vulnerability of the scheme to the identified climate and weather-related
risks (
Table 14.18). Further adaptation mitigation measures are likely to be integrated into the
detailed design at PCF Stage 5 – Construction Preparation.
Table 14.19 - Significant Risks and Planned Mitigation Measures for the Scheme
RISK
MITIGATION MEASURES
The drainage design includes Sustainable Drainage Systems (SuDs) to reduce
surface water flooding and a climate change factor of 40% on rainfal .
Increased
The increase in impermeable surface area has been taken into account in the
precipitation
drainage design. The Shared Use Path however is likely to be managed
separately to the existing carriageway.
The length of culverts (where appropriate) have been increased on the Shared
Use Path and boardwalks have been used where possible.
A dust management plan wil be developed.
Drought
Water efficiency measures wil be implemented at PCF Stage 5.
Drought resistant vegetation wil be considered at PCF Stage 5.
Undercutting
The ground covering/ material wil be designed at PCF Stage 5, taking into
and scour
account outputs from flood model ing.
Soil moisture
Current standards for geotechnical design wil be utilised when designing slopes,
and stability
with appropriate margins incorporated to account for changes in moisture and
stability.
Extreme
Al equipment wil be to current design standards as used throughout the Highways
temperatures
England network.
(overheating
The Polegate Railway Bridge widening aspect has been designed to Eurocodes
equipment,
and DMRB which include measures for wind and thermal action. These cover
fires):
extreme events commensurate with a 120 year design life.
The new cycle / foot bridge over the River Cuckmere and Polegate Railway Bridge
widening aspects have been designed to Eurocodes and DMRB which include
Gales and
measures for wind and thermal action. These cover extreme events
extreme wind
commensurate with a 120 year design life.
events
Aspects such as signage, lighting, CCTV masts wil al be designed for wind
loading, anticipated to account for high wind forces, This wil be further considered
during detailed design (PCF Stage 5).
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The scheme has been designed to minimise maintenance requirements, for
Delays and
example the sealed surface of the Shared Use Path wil last longer than gravel or
reduced
other similar material.
maintenance
opportunities
Al equipment wil be to current design standards as used throughout the Highways
impacting
England network.
business
Further operational and maintenance business continuity aspects wil be reviewed
continuity
and adopted by A1+ (Highways England Maintenance Contractor for the south-
east).
Extreme
weather
events
Operational and maintenance health and safety aspects wil be reviewed and
impacting on
adapted by A1+ (Highways England Maintenance Contractor for the south-east).
health and
safety
14.13.12
Further mitigation and resilience to climate and weather-related risks wil be considered
periodical y through maintenance regimes. For example, regular inspections (at minimum two
and six yearly intervals) wil be undertaken for structures to mitigate the impacts of excessive
vegetation growth and deterioration of materials. Inspections wil also occur fol owing an
extreme weather event to monitor any damage and implement appropriate mitigation as
necessary.
14.13.13
A list of weather related incidents (for example, road surface deformations, snow and ice)
would be maintained to assist in identifying thresholds which, when exceeded, require
maintenance.
RESIDUAL EFFECTS
14.13.14
Where a significant pre-mitigation climate risk was found (
Table 14.18), the level of resilience
has been determined based on the integration of the above planned mitigation measures
(presented in
Table 14.19). Where it has been indicated by the design team that mitigation
measures wil be considered further at a later stage of the design process, the resilience
ratings in
Table 14.20 below are dependent on that further consideration and incorporation of
mitigation taking place.
14.13.15 The conclusions of this analysis or resilience and residual significance are presented in
Table
14.20.
Table 14.20 - Climate resilience rating following integration of the proposed mitigation
measures
COMPONENT
IMPACT
RISK
RESILIENCE RESIDUAL
RATING
EFFECT
Damage to carriageway
structures due to increased
High
Not
runoff.
Significant
Extreme
Structural
rainfal
Undercutting and scour
Stability
particularly in relation to the
bridge over the Cuckmere
Moderate
Not
Significant
River.
Drought
Loss of vegetation leading
to greater erosion risk.
High
Not
Significant
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Overheating of equipment,
Extreme
including during
temperature
construction and operation
High
Not
(such as electronic
Significant
signage)
Risk of damage to
structures and foundations,
Gales and
including flood scour and/or
Moderate
Not
Significant
extreme wind
runoff.
events
Damage to signage and
site structures.
High
Not
Significant
Shrinking and cracking of
soils leading to subsidence.
Moderate
Not
Significant
Soil softening and erosion
Not
leading to col apse and
Significant
settlement of soil
Moderate
Soil moisture
structures.
Increased slope instability.
Moderate
Not
Significant
Soil saturation.
Moderate
Not
Significant
Subsidence impacting
Not
road, cycleway and
Significant
footpath and bridges over
Moderate
the Cuckmere River.
Stability
Failure of earthworks due
to desiccation.
Moderate
Not
Significant
Shrinking and cracking of
soils.
Moderate
Not
Significant
Structural
Extreme
Damage and disruption
robustness
temperature
(e.g. fires).
High
Not
Significant
Drought
Damage and disruption
(fires).
High
Not
Significant
Extreme
Higher day and night-time
temperature
temperatures.
High
Not
Significant
Shrinking and cracking of
soils leading to subsidence.
Moderate
Not
Significant
Ancil ary
Soil softening and erosion
Not
equipment
Soil moisture
leading to col apse and
Significant
settlement of soil
Moderate
structures.
Increased rate of
Not
Stability
deterioration, potential y
Significant
leading to need for early
Moderate
replacement.
Increased rate of
Material
Gales and
deterioration of materials,
durability
extreme wind
High
Not
events
potential y leading to early
Significant
replacement.
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Water accumulation
causing disruption to
High
Not
construction and operation.
Significant
Stopping of services due to
asset failure.
High
Not
Significant
Scour of embankments
Not
Extreme
leading to increased
Moderate
Significant
rainfal
maintenance.
Traf ic disruption and
Site contents
congestion.
High
Not
Significant
and business
continuity
Excessive vegetation
growth.
High
Not
Significant
Reduced opportunities for
maintenance.
High
Not
Significant
Reduced working periods
and delays.
High
Not
Significant
Extreme
Reduced opportunities for
temperature
maintenance.
High
Not
Significant
Operational disruption.
High
Not
Significant
Dif icult working conditions.
High
Not
Significant
Extreme
Movement of debris
Not
rainfal
causing slip, trip and fal
Moderate
Significant
hazards.
Health and safety risks to
road users.
Moderate
Not
Significant
Drought,
including long
periods of dry
More dust.
High
Not
Significant
weather
H&S of users
Dif icult working conditions.
High
Not
(operators
Significant
and
Increased fire risk.
customers)
High
Not
Significant
Extreme
Hot surfaces may cause
temperature
injury.
High
Not
Significant
Failure of temperature
controls.
High
Not
Significant
Health and safety risks to
road users.
High
Not
Significant
Dif icult working conditions.
High
Not
Gales and
Significant
extreme wind
Health and safety risks to
events
road users particularly high
High
Not
sided vehicles).
Significant
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14.13.16
As presented in
Table 14.20, many climate risks have been assessed to have a high resilience
rating when taking account of the planned mitigation measures described in
Table 14.19 -
Significant Risks and Planned Mitigation Measures for the Scheme (i.e. where it is considered
that there is a strong degree of climate resilience) and are deemed to be not significant.
14.13.17
The application of the mitigation measures wil be closely monitored as the detailed design
progresses and as operational and maintenance management plans are developed.
14.13.18
Given the uncertainties inherent in climate science and the associated projections used in this
assessment, it is recommended that the vulnerabilities and risks identified in this assessment
are monitored throughout the design, construction and operational phases of the scheme. The
monitoring would be undertaken to assess the appropriateness of the mitigation measures,
and be revisited when new or updated information becomes available.
14.14
CLIMATE CHAPTER SUMMARY
14.14.1
The GHG assessment has concluded that the scheme wil have an effect of neutral
significance on GHG emissions during construction and operational phases.
Table 14.10
provides a summary of the effects.
14.14.2
The climate resilience assessment has concluded that, due to the planned mitigation
measures, the climate risks have a high resilience rating and are deemed to be not significant.
Table 14.20 provides a summary of the climate resilience rating and residual effect.
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