Volume 1, Chapter 10 Climate change...2019/06/12 · Climate change 10.1 Introduction 10.1 Relevant legislation, policy and other important and relevant matters 10.3 Introduction

Heathrow Expansion PRELIMINARY ENVIRONMENTAL INFORMATION REPORT

© Heathrow Airport Limited 2019

Volume 1, Chapter 10

Climate change

Heathrow Expansion PRELIMINARY ENVIRONMENTAL INFORMATION REPORT: Chapter 10: Climate Change


CONTENTS

10. Climate change 10.1

Introduction 10.1

Relevant legislation, policy and other important and relevant matters 10.3 Introduction 10.3 Legislation and national planning policy 10.3 Regional and local planning policy 10.7 Other important and relevant matters 10.8

Scoping and engagement 10.8 Overview 10.8 Scoping Opinion 10.8 Technical engagement 10.11

Scope of the assessment 10.12 Overview 10.12 Spatial scope and study area 10.12 Temporal scope 10.14 Project parameters and reasonable worst case 10.14 Receptors 10.15 Identification of potential effects 10.17

Embedded environmental measures 10.24

Methodology for baseline data gathering 10.32 Desk study 10.32

Assessment methodology for PEIR 10.33 Assessment methodology evolution 10.33 Climate hazards assessment 10.34 In-combination climate change impact assessment 10.39 Climate change resilience assessment 10.43

Assumptions and limitations of this PEIR 10.48

Overall baseline 10.49 Current baseline 10.49 Future baseline 10.51

Assessment of climate change effects 10.51 Introduction 10.51 Hazard assessment 10.51 In-combination climate change impact assessment 10.56 Climate change resilience assessment 10.67

Preliminary assessment of significance 10.83

Assessment of cumulative effects 10.84

Consideration of additional environmental measures and compensation 10.84

Next Steps 10.84 Introduction 10.84 Baseline 10.84 Assessment 10.84 Engagement 10.85



TABLE OF TABLES

Table 10.1: Legislation relevant to climate change 10.3 Table 10.2: National planning policy relevant to climate change 10.4 Table 10.3: PINS Scoping Opinion consultation 10.9 Table 10.4: Aspects scoped into the in-combination climate change impact assessments 10.15 Table 10.5: Assets scoped into the climate change resilience assessment 10.16 Table 10.6: Potential effects from in-combination climate change impacts on receptors 10.17 Table 10.7: Potential effects of climate change on asset groups 10.22 Table 10.8: Summary of the embedded environmental measures in the design and how these influence the climate change assessment for both the ICCI and CCR assessments 10.25 Table 10.9: Summary of the good practice environmental measures and how these influence the climate change assessment 10.28 Table 10.10: Data sources used to inform the climate change assessment 10.32 Table 10.11: Assessment methodology for the PEIR and ES 10.33 Table 10.12: Climate variables that have been assessed in the climate hazards assessment 10.35 Table 10.13: Derived hazards that have been assessed in the climate hazards assessment 10.36 Table 10.14: Criteria to assess likelihood of hazard (based upon UKCP18) 10.36 Table 10.15: Criteria to assess likelihood of climate change impact 10.46 Table 10.16: Criteria used to assess consequence of a climate change impact 10.47 Table 10.17: Criteria used to assess risk levels for the climate change resilience assessment 10.48 Table 10.18: Future changes in climate variables for 2030s, 2050s, 2080s and 2099 10.52 Table 10.19: Direction of change in hazards for 2020s, 2050s and 2080s 10.55 Table 10.20: In- combination Climate Change impact assessment results 10.57 Table 10.21: Climate change resilience assessment results 10.68 Table 10.22: Further engagement 10.85

TABLE OF GRAPHICS

Graphic 10.1: UKCP18 representative 25km2 and 12km2 grid squares, relevant to the DCO Project 10.13 Graphic 10.2: Methodological approach to in-combination climate change impact assessment 10.41 Graphic 10.3: Risk framework for climate change resilience assessment 10.45

APPENDICES

Appendix 10.1: Principles of the Climate Change Adaptation Plan


10.1 © Heathrow Airport Limited 2019

10. CLIMATE CHANGE

Introduction

10.1.1 This chapter of the Preliminary Environmental Information Report (PEIR) presents

the preliminary results of the assessment of the likely significant effects of the

impacts of climate change on the Development Consent Order Project (’DCO

Project’). This includes both the in-combination climate change impacts (ICCI) and

climate change resilience (CCR) assessments. This chapter should be read in

conjunction with the DCO Project description provided in Chapter 6: DCO Project description, Chapter 23: Bibliography, and the Glossary of terms and abbreviations.

10.1.2 This chapter describes data and information relevant to the ICCI assessment and

the CCR assessment. The ICCI assessment focusses on those effects of the DCO

Project identified by an environmental aspect that will also be affected by climate

change. An example of this is the fragmentation of a habitat, which could be

exacerbated by projected increases in temperature and frequency of droughts.

10.1.3 The CCR assessment focuses on the resilience of the DCO Project to projected

future climate change effects. An example of this is increased intensity of extreme

rainfall events creating volumes of surface water run-off that overwhelm the

drainage infrastructure.

10.1.4 Where data and information are common to both assessments, this is explained in

the text. Where data and information are specific to each assessment, separate

sub-headings are used.

10.1.5 The effect of the DCO Project on climate change is the focus of Chapter 9: Carbon and greenhouse gases.

10.1.6 This chapter describes:

The planning policy, legislation and other relevant documentation that has

informed the assessment (Section 10.2: Relevant legislation, policy and other important and relevant matters)

The outcome of consultation and external engagement that has been

undertaken, including how matters on climate change within the Scoping

Opinion adopted in July 2018 have been addressed (Section 10.3: Scoping and engagement)

The scope of the assessment for climate change (Section 10.4: Scope of the assessment)



Embedded environmental measures relevant to climate change (Section 10.5: Embedded environmental measures)

The methods used for the baseline data gathering (Section 10.6: Methodology for baseline data gathering)

The assessment methods used for the PEIR (Section 10.7: Assessment methodology for PEIR)

The assumptions and limitations of the PEIR assessment (Section 10.8: Assumptions and limitations of this PEIR)

The overall baseline (Section 10.9: Overall baseline)

The assessment of climate change effects (Section 10.10: Assessment of climate change effects)

A summary of significance of positive and negative climate change effects

identified in the PEIR (Section 10.11: Preliminary assessment of significance)

The assessment of cumulative effects (Section 10.12: Assessment of cumulative effects)

Consideration of any additional environmental measures or compensation

required (Section 10.13: Consideration of additional environmental measures and compensation)

An outline of further work to be undertaken for the Environmental Statement

(ES) (Section 10.14: Next steps).

10.1.7 In-combination effects are addressed in Chapter 22: In-combination effects.

10.1.8 In the context of this chapter, ‘adaptation’ is an adjustment to a design or

operational procedure to respond to the projected impacts of climate change.

‘Climate change resilience’ of the DCO Project is its ability to absorb the impacts

of climate change and maintain its functionality. This can be increased through the

introduction of adaptation measures, which are referred to as ‘environmental

measures’ for consistency with the rest of the PEIR. Any reference to ‘mitigation’

or ‘mitigating’ an effect is used in this chapter in the context of the EIA terminology,

and not in the context of mitigating global climate change through the reduction of

greenhouse gas (GHG) emissions (which is the focus of Chapter 9).

10.1.9 This chapter uses the UK Climate Projections 2018 (UKCP18) (Met Office, 2018)

as the basis of assessment. UKCP18 (Met Office, 2018) was released on 26th

November 2018, replacing UKCP09 (Met Office, 2009) as the de facto climate

projections for use in climate change impact and adaptation assessment in the

UK.



Relevant legislation, policy and other important and relevant matters

Introduction

10.2.1 This section identifies the policy and legislation that has informed the assessment

of effects for climate change. Further information on policies relevant to the EIA

and their status is provided in Chapter 2: Legislative and policy overview of this

PEIR.

Legislation and national planning policy

10.2.2 Table 10.1 lists the legislation relevant to the assessment of the effects on climate

change receptors for the ICCI and CCR assessments.

Table 10.1: Legislation relevant to climate change

Legislation description Relevance to assessment

UK Climate Change Act 2008

Section 56 of the Climate Change Act 2008

commits the UK to producing a Climate Change

Risk Assessment (CCRA):

’It is the duty of the Secretary of State to lay reports

before Parliament containing an assessment of the

risks for the United Kingdom of the current and

predicted impact of climate change.’

This includes a mechanism under which certain

organisations report on their preparedness in

relation to climate change. The Secretary of State

directed a number of infrastructure owners and

operators, including Heathrow, to report for the first

round of reporting. The second and third rounds of

reporting are voluntary.

The CCRA must be prepared at no longer than five-

yearly intervals. To date two CCRAs have been

produced (Defra, 2017a). Paragraph 4.49 of the

Airports National Policy Statement (ANPS)

(Department for Transport, 2018) requires that

adaptation measures proposed are based on the

most recent CCRA (Defra, 2017a).

The Climate Change Act 2008 introduced an

obligation on the Secretary of State to prepare the

The UK Climate Change Act 2008 requires

Heathrow to report on how they are addressing

current and future climate effects. Heathrow has

developed two reports on progress in climate

change adaptation: the UK Climate Change

Adaptation Reporting Power Report (Heathrow

Airport Limited, 2011), which identified the key

climate risks to the infrastructure and operations of

Heathrow Airport, and; the Heathrow Airport

Climate Change Adaptation and Resilience

Progress Report (Heathrow Airport Limited, 2016),

which updated on Heathrow’s progress in meeting

resilience actions identified in the Climate Change

Adaptation Reporting Power Report (Heathrow

Airport Limited, 2011). The third round of adaptation

reporting under the NAP is currently ongoing.

These existing adaptation reporting processes are

relevant to this PEIR assessment as all climate

change risk assessment and associated

environmental measures identified through this

assessment will feed into Heathrow’s reporting

thereafter. The existing adaptation assessments for

Heathrow is therefore considered in the

methodology described in Section 10.7 of this

chapter. The approach to considering the CCRAs

that are required by the UK Climate Change Act

2008 is described in Section 10.7 of this chapter.



Legislation description Relevance to assessment

National Adaptation Programme (NAP) in section

58 (1). It states:

‘It is the duty of the Secretary of State to lay

programmes before Parliament setting out —

(a) the objectives of Her Majesty’s Government in

the United Kingdom in relation to adaptation to

climate change,

(b) the Government’s proposals and policies for

meeting those objectives, and

(c) the time-scales for introducing those proposals

and policies, addressing the risks identified in the

most recent report under section 56.’

The NAP must contribute to sustainable

development and should be presented as soon as

possible after the CCRA.

10.2.3 Table 10.2 lists the national planning policy relevant to the assessment of the

effects on climate change receptors.

Table 10.2: National planning policy relevant to climate change

Policy description Relevance to assessment

Airports National Policy Statement (ANPS)

Chapter 2 provides an explanation of the relevance of the ANPS (Department for Transport, 2018) to the DCO Project in general terms. The ANPS (Department for Transport, 2018) regards climate change as an assessment principle. Paragraph 4.45 states: ’New airports infrastructure will typically be a long-term investment which will need to remain operational over many decades, in the face of a changing climate. Consequently, the applicant must consider the impacts of climate change when planning design, build and operation. Any accompanying environmental statement should set out how the proposal will take account of the projected impacts of climate change.’ In Paragraphs 4.46 to 4.52, the ANPS (Department for Transport, 2018) requires the assessment to include the following:

1. “Detailed consideration must be given to the

range of potential impacts of climate change

using the latest UK Climate Projections

available at the time, and to ensuring any

environmental statement that is prepared

The ANPS (Department for Transport, 2018) sets out requirements for the assessment, which are followed in the methodology provided in Section 10.7 of this chapter:

1. The assessment methodology outlined in this

PEIR ensures identification of climate change

impacts using UKCP18 (the latest set of UK

climate projections) (Met Office, 2018), as

described in Section 10.7 of this chapter. Table 10.8 sets out how embedded environmental

measures will be implemented in relation to

climate change.

2. The use of probability levels from the 10% to the

90%, including the 50%, is described in Table 10.14 assessment of this assessment. The use

of the high emissions scenario in the 2080s for

long-lived assets is described in Section 10.7 of

this chapter.

3. ‘More radical changes’ to the climate will be

considered in the ES through the use of

sensitivity analysis. An adaptive management

approach will be used to consider such

changes, as described in Appendix 10.1:




identifies appropriate mitigation or adaptation

measures.

2. Where transport infrastructure has safety-

critical elements, and the design life of the

asset is 60 years or greater, the applicant

should apply the latest available UK Climate

Projections, considering at least a scenario that

reflects a high level of greenhouse gas

emissions at the 10%, 50% and 90% probability

levels, to assess the impacts of climate change

over the lifetime of the development.

3. The applicant should demonstrate that there

are no critical features of infrastructure design

which may be seriously affected by more

radical changes to the climate beyond those

projected in the latest set of UK Climate

Projections. Any potential critical features

should be assessed, taking account of the

latest credible scientific evidence on, for

example, sea level rise, and on the basis that

necessary action can be taken to ensure the

operation of the infrastructure over its estimated

lifetime through potential further mitigation or

adaptation.

4. Any adaptation measures should be based on

the latest set of UK Climate Projections (Met

Office, 2018), the most recent UK Climate

Change Risk Assessment (Defra, 2017a),

consultation with statutory consultation bodies,

and any other appropriate climate projection

data. Any adaptation measures must

themselves also be assessed as part of any

Environmental Impact Assessment and

included in the environmental statement, which

should set out how and where such measures

are proposed to be secured.

5. If any proposed adaptation measures

themselves give rise to consequential impacts,

the Secretary of State will consider the impact

in relation to the application as a whole and the

assessment principles set out in the Airports

NPS.

6. Adaptation measures can be required to be

implemented at the time of construction where

necessary and appropriate to do so.

7. Where adaptation measures are necessary to

deal with the impact of climate change, and that

measure would have an adverse effect on other

aspects of the DCO Project or the surrounding

environment, the Secretary of State may

consider requiring the applicant to ensure that

the adaptation measure could be implemented

Principles of the Climate Change Adaptation Plan, Volume 3.

4. The consideration of the UK CCRA (Defra,

2017a) in the methodology is described in

Section 10.7 of this chapter. Table 10.3 sets

out the responses to Planning Inspectorate

(PINS) comments. Section 10.3 onwards

outlines engagement with key stakeholders.

Environmental measures (a term used instead

of mitigations in this PEIR) have been

developed to manage risks. These are

described in Section 10.5 of this chapter, and

Appendix 10.1. 5. The consequential impacts of embedded

environmental measures in other aspects have

been assessed in their individual chapters;

since no additional environmental measures

have been identified yet for climate change,

there have been no consequential impacts to

consider.

6. Environmental measures have been

incorporated into the design of the DCO Project

that is to be constructed.

7. Environmental measures to be incorporated

throughout the operational lifetime of the DCO

Project are incorporated into Appendix 10.1.




should the need arise, rather than at the outset

of the development.’

National Policy Statement for National Networks (NN NPS)

Chapter 2 provides an explanation of the relevance of the NN NPS (Department for Transport, 2014) to the DCO Project in general terms. In a similar way to the ANPS (Department for Transport, 2018), paragraph 4.37 of the NN NPS sets out: ‘how the NPS puts Government policy on climate change adaptation into practice, and in particular how applicants and the Secretary of State should take the effects of climate change into account when developing and consenting infrastructure.’ The NN NPS (Department for Transport, 2014) wording is similar to that in the ANPS (Department for Transport, 2018), except in paragraph 4.41 which specifies that: ‘where transport infrastructure has safety-critical elements and the design life of the asset is 60 years or greater, the applicant should apply the UK Climate Projections 2009 (UKCP09) high emissions scenario (high impact, low likelihood) against the 2080 projections at the 50% probability level.’

Given the inclusion of the M25 works as part of the Development Consent Order Project (‘DCO Project’), the requirements of the NN NPS relating to climate change are applicable (Department for Transport, 2014). Further details of the proposed works to the M25 are set out in Chapter 6 of this PIER. It is a requirement of the NN NPS (Department for Transport, 2014) to undertake an assessment of the climate change impacts on the M25 component of the DCO Project and implement environmental measures accordingly. The NN NPS (Department for Transport, 2014) sets out requirements for the assessment, which are followed in the methodology provided in Section 10.7 of this chapter. Projections in the high scenario at the 50%

probability level are inherently used in the

assessment as the 10th – 90th percentile range is

considered, as described in Table 10.14.

Therefore, the requirements of the NN NPS

(Department for Transport, 2014) are exceeded in

order to meet the requirements of the ANPS

(Department for Transport, 2018).

National Planning Policy Framework (NPPF)

The NPPF (DCLG, 2019) sets out the Government’s planning policies for England. Chapter 2 provides an explanation of the relevance of the NPPF (DCLG, 2019) to the DCO Project in general terms. The NPPF (DCLG, 2019) sets out in paragraph 149

that Local Plans:

‘should take a proactive approach to mitigating and

adapting to climate change, taking into account the

long-term implications for flood risk, coastal

change, water supply and changes to biodiversity

and landscape’.

Paragraph 150 states that:

‘New developments should be planned for in ways

that:

a) avoid increased vulnerability to the range of impacts arising from climate change. When new development is brought forward in areas which are vulnerable, care should be taken to ensure that risks can be managed through suitable adaptation

The NPPF (DCLG, 2019) and the associated EA planning practice guidance (Environment Agency, 2017) requires a risk-based approach to avoid vulnerability associated with flooding risk and climate change. The methodology outlined in Section 10.7 of this chapter ensures that the vulnerability of the DCO Project to climate change is assessed, and environmental measures are implemented to ensure risks are managed.




measures, including through the planning of green infrastructure’. Paragraph 153 also states that: ’in determining planning applications, local planning authorities should expect new development to: a) comply with any development plan policies on local requirements for decentralised energy supply unless it can be demonstrated by the applicant, having regard to the type of development involved and its design, that this is not feasible or viable’. The supporting Environment Agency planning

practice guidance, Flood risk assessments: climate

change allowances (Environment Agency, 2017),

contains the percentage uplifts for climate change

to be added to assessments. Local Planning Authorities (LPAs) are required to set out the strategic priorities for the area in their Local Plans, and this should include policies to deliver climate change mitigation and adaptation (among other priorities). Therefore, the NPPF climate change principles (DCLG, 2019) are reflected in the Local Plans relevant to the DCO Project, as listed in Appendix 2.1.

Regional and local planning policy

10.2.4 Appendix 2.1: Regional and local planning policy and other important and relevant matters, Volume 3 presents the full list of the regional and local planning

policies relevant to the assessment of the effects on climate change receptors.

10.2.5 Only those authorities that the DCO Project is situated within or in which new

buildings will be required are relevant to this chapter given the potential for

localised effects from climate hazards. The local planning policies from the

following LPAs, which fall within the climate change study area (Section 10.4),

have therefore been considered:

1. Greater London Authority

2. London Borough of Hillingdon

3. London Borough of Hounslow

4. Royal London Borough of Windsor and Maidenhead

5. Spelthorne Borough Council

6. Slough Borough Council



7. South Bucks District Council

8. Buckinghamshire County Council

9. Surrey County Council.

Other important and relevant matters

10.2.6 A summary of other relevant documentation to the assessment undertaken in

climate change is provided in Table 4.2 of Appendix 2.1.

Scoping and engagement

Overview

10.3.1 This section describes the outcome of, and response to, the Scoping Opinion in

relation to the climate change assessment. It also provides details of the ongoing

technical engagement that has been undertaken with stakeholders and individuals.

An overview of engagement undertaken can be found in Section 1.5 of Chapter 1: Introduction.

10.3.2 Engagement has taken the form of meetings and document sharing, and is

summarised in the following sections.

Scoping Opinion

10.3.3 A Scoping Report requesting a Scoping Opinion was submitted to the Secretary of

State, administered by the Planning Inspectorate (PINS) on behalf of the Secretary

of State, on 21 May 2018. The Scoping Report set out the proposed climate

change assessment methodologies, outlined the baseline data collected to date

and that proposed for the ES.

10.3.4 A Scoping Opinion was adopted by PINS, on behalf of the Secretary of State, on 2

July 2018. Table 10.3 sets out the comments adopted in Section 4 of the PINS

Scoping Opinion (‘Aspect based scoping tables’) for climate change and how they

have been addressed in this PEIR. A full list of the PINS Scoping Opinion

comments and responses is provided in Appendix 5.1: Response to the Scoping Opinion, Volume 3. The information provided in the PEIR is preliminary

and therefore not all the Scoping Opinion comments have been addressed at this

stage. However, all comments will be addressed within the ES.



Table 10.3: PINS Scoping Opinion consultation

PINS ID number Scoping Opinion comment How is this addressed?

53 The Scoping Report states that no effects

have been scoped out of the ICCI and CCR

assessments but that Phase 1 of the ICCI

assessment will consider all aspects (topics)

and will determine which aspects remain

scoped in for detailed assessment and which

are scoped out. Any aspects or matters

subsequently scoped out of the assessment

should be fully justified within the ES and

efforts made to agree these with relevant

consultation bodies.

Engagement has been carried out through an

integrated approach with the other

environmental aspects. Further engagement

with relevant consultation bodies will be

undertaken to inform the ES.

54 The Inspectorate notes that the Applicant has

consulted the Environment Agency regarding

the proposed approach with respect to the

water environment and intends to consult with

the Heathrow Strategic Planning Group

(HSPG). The Applicant should ensure that

other consultation bodies with statutory

responsibilities for other assessment aspects

(for example, biodiversity), such as Natural

England, are consulted regarding the potential

for climate change effects to influence the

effectiveness of any proposed mitigation

measures.

For the PEIR stage, climate change has been

considered in an integrated approach with

the other environmental aspects. The

Environment Agency, Natural England,

Public Health England and HSPG will be

engaged with specifically on the subject of

climate change for the ES stage.

55 The ES should take into account the potential

impacts of climate change using the latest

UKCP available at the time of preparation.

This should include where appropriate the

anticipated UKCP18 projections.

UKCP18 (Met Office, 2018) has been used in

the production of this PEIR.

UKCP18 (Met Office, 2018) was released in

November 2018, however, the anticipated

2.2km resolution projections were not

available at the time of publishing the PEIR

and are therefore not included. The full suite

of UKCP18 (Met Office, 2018) tools will be

used in the production of the ES.

56 The Inspectorate notes that based on the

nature of the Proposed Development, for the

purpose of the climate change assessments its

operational period is estimated as being 100

years. The Scoping Report describes the use

of ’intermediate timeframes’ to allow

consideration of infrastructure elements with

more short-lived operational periods. The

Inspectorate advises that the ES includes

details of any infrastructure elements predicted

to be decommissioned over a shorter time

period and give consideration to the potential

Assets and receptors with design lives

shorter than 100 years have been considered

in the assessment (for example, runways,

taxiways), and the temporal scale of the

climate change projections used are in-line

with those design lives as described in

Section 10.4. This consideration of different

design lives, replacement and maintenance

cycles and impact thresholds has been used

in the development of environmental

measures as described in Section 10.5 of

this chapter and the principles of the Climate



PINS ID number Scoping Opinion comment How is this addressed?

for likely significant effects to arise in relation

to these elements.

Change Adaptation Plan (CCAP) (Appendix 10.1).

These assets are not considered to be

’decommissioned’ as they enter replacement

and maintenance cycles during the

operational phase.

57 The ES should set out the assumptions and

uncertainties in the projections and explain

how these have informed the climate change

risk and resilience assessments and

influenced the design of the Proposed

Development.

Assumptions and uncertainties in the climate

change projections used, and how that is

considered in the climate change hazard

assessment carried out for both the ICCI and

CCR assessments, have been described in

Section 10.7 and Section 10.8 of this

chapter.

58 The ES should explain the duration of any

temporary effects, ensuring consistency with

the other aspect assessments.

Consideration of temporary effects is

inherently incorporated into the assessment

as the initial significance of effect identified

by the aspect chapter (for instance, without

climate change) is the starting point of the

ICCI assessment, and temporary effects are

considered in the consequence criteria

identified for the CCR assessment in Table 10.16.

59 The final study areas for the ICCI and CCR

assessments should encompass the Proposed

Development and any associated development

that the Applicant tends to include within its

application for development consent.

Both the ICCI and CCR assessments

encompass the DCO Project and any

associated development within the Site.

60 The Inspectorate advises that the ES should

clearly explain which mitigation measures

would be ‘embedded’ and which would

comprise further or additional mitigation

including those incorporated into the Climate

Change Adaptation Plan which is intended to

be included in the application for development

consent. The ES should set out how mitigation

measures will be secured through the DCO.

The ES should describe how the adaptation

measures incorporated into a Climate Change

Adaptation Plan will address the need for on-

going review of climate ’hazards‘ and risks.

The assessment defines which

environmental measures are embedded and

which are good practice. Embedded

environmental measures are those directly

included in the design as a result of the ICCI

and CCR assessments. As a result of the

incorporation of the CCAP as an embedded

measure, there are no additional

environmental measures required.



Technical engagement

10.3.5 Technical engagement has been ongoing with a number of prescribed and non-

prescribed consultation bodies and LPAs in relation to climate change. A summary

of engagement undertaken up to finalisation of this PEIR is outlined in this section.

Environment Agency

10.3.6 Engagement with the Environment Agency has been ongoing since April 2018

through incorporating climate change into the wider regular engagement on flood

risk from all sources, as detailed in Chapter 21: Water environment.

10.3.7 The approach for accounting for the possible effects of climate change in the

Flood Risk Assessment (FRA) and Drainage Impact Assessment (DIA) pays due

regard to local and national policy requirements, which have been discussed with

the Environment Agency as part of the preparation of the FRA and DIA for PEIR

respectively. The specifics can be found in the FRA and DIA which are Appendix 21.4: Flood risk assessment, Volume 3 and Appendix 21.5: Drainage impact assessment, Volume 3, respectively.

10.3.8 The main aim of engagement with the Environment Agency has been to discuss

the consideration of climate change in the assessments of flooding from

groundwater sources and the resultant environmental measures.

10.3.9 Climate change not being considered within the groundwater assessment for PEIR

was discussed, and further engagement to confirm the approach taken for ES will

be carried out in the Summer of 2019. Additionally, the Environment Agency

indicated that they would not be commenting further on climate change issues

outside of the scope of Chapter 21.

Natural England

10.3.10 Engagement with Natural England in relation to the DCO Project has been

ongoing since 11 November 2016 in the form of technical meetings and

workshops, site visits and the sharing of draft technical documentation. Further

engagement with Natural England on the development of climate change

principles for biodiversity environmental measures will be carried out ahead of the

ES.

Public Health England

10.3.11 Heathrow contacted Public Health England (PHE) in November 2017 and May

2018 to invite PHE to be a member of Heathrow Strategic Planning Group (HSPG)

Health Group.

10.3.12 Heathrow met with PHE in March 2019 to discuss assessment methods. The

topics discussed included the scope of, and the method for, the assessment of



human health. Further engagement with PHE on the development of climate

change principles for health environmental measures will be carried out ahead of

the ES.

Heathrow Strategic Planning Group

10.3.13 Engagement with the HSPG has been ongoing since May 2018 in the form of

meetings specific to the climate change approach for the EIA.

10.3.14 The aim of engagement with HSPG has been to share the approach to the climate

change assessment in the PEIR. This includes consideration of impacts with

localised effects.

10.3.15 HSPG sought clarification that certain ICCIs were to be qualitatively included in the

PEIR assessment, such as increased heatwaves impacting air quality and

exacerbating Urban Heat Island effects on communities. These topics are

addressed in Section 10.4.

10.3.16 The approach for accounting for the possible effects of climate change in the FRA

and DIA pays due regard to local and national policy requirements, which have

been discussed with HSPG as part of the preparation of the FRA and DIA for PEIR

respectively. The specifics can be found in the FRA and DIA which are Appendix 21.4 and Appendix 21.5 respectively.

Scope of the assessment

Overview

10.4.1 This section describes the spatial and temporal scope for the assessment as it

applies to climate change and outlines the receptors on which assessment has

been undertaken (Table 10.4 and Table 10.5).

10.4.2 The scope has been developed as the DCO Project has evolved, and responds to

feedback received to date, as detailed in Section 10.3. The information presented

in the PEIR is by its nature preliminary and in accordance with PINS Advice Note

Seven, should not be considered a ‘draft’ ES but can be presented in this way if

appropriate. Further scope refinement may be required to take full account of the

preferred DCO Project design and subsequent engagement.

Spatial scope and study area

In-combination climate change impact assessment

10.4.3 The study area for the ICCI assessment has been defined by the study area

boundaries for each of the environmental aspects (refer to relevant chapters of this

PEIR, from Chapter 7: Air quality and odour to Chapter 21).



10.4.4 The most representative 25km2 UKCP18 grid square for the DCO Project provided

the relevant climate data for the ICCI assessment. Where the most appropriate

data was from the 12km2 regional projections within UKCP18, the relevant grid

square for this dataset was used instead (Met Office, 2018) (Graphic 10.1).

Graphic 10.1: UKCP18 representative 25km2 and 12km2 grid squares, relevant to the DCO Project

Climate change resilience assessment

10.4.5 The study area for the CCR assessment comprised:



1. The land within the existing airport boundary

2. The land within the Site for the DCO Project.

10.4.6 The study area includes associated developments, as described in Chapter 6.

10.4.7 The most relevant 25km2 UKCP18 grid square for the DCO Project provided the

relevant climate data for the assessment. Where the most appropriate data was

from the 12km2 regional projections within UKCP18, the relevant grid square for

this dataset was used instead (Met Office, 2018) (Graphic 10.1).

Temporal scope

10.4.8 The potential impacts of climate change increase over time. Therefore, in the

assessments of climate change within this chapter, the potential impacts

experienced by the receptor or asset will be largest at the end of its design life.

Where assets are assumed to be in operation in perpetuity, potential impacts will

be greatest at the furthest extent of the UKCP18 projections (Met Office, 2018).

Construction

10.4.9 Construction works are planned to commence in 2022 and activities will be phased

over a period of 28 years. Therefore, 2050 is used for construction activities to

represent the reasonable worst-case approach.

Operation

10.4.10 For receptors or assets that are in place in perpetuity, the end of the 21st century is

taken as the most relevant time to assess climate change impacts in-line with

UKCP18 projections (Met Office, 2018). Therefore, neither the ‘core’ assessment

years (key years relating to milestones in the construction and operational phases

of the DCO Project, Section 5.4 of Chapter 5) or ‘additional’ assessment years

(years likely to result in the reasonable worst case effects for a particular aspect,

Section 5.4 of Chapter 5), are relevant to the assessment of climate change.

Instead the estimated end of the design life of each receptor or asset is used.

10.4.11 The assessment year used for each receptor or asset is implicitly the reasonable

worst-case as climate change impacts increase over time.

Project parameters and reasonable worst case

10.4.12 As outlined in Chapter 5, to provide flexibility in the design of the DCO Project

post grant of the DCO and at the same time maintain a rigorous EIA process, a

reasonable worst-case approach has been taken for each aspect assessment. For

the purposes of defining a reasonable worst case for climate change, a

conservative approach has been taken to the design lives of receptors and assets



for the climate change assessments. The Representative Concentration Pathway

(RCP) 8.5 UKCP18 emissions scenario (Met Office, 2018) (the ‘high’ emission

scenario) has been used to assess climate change effects.

Receptors

Introduction

10.4.13 This section describes the receptors considered in the ICCI and CCR

assessments.


10.4.14 The spatial and temporal scope of the assessment enables the identification of

receptors that may experience a change because of the DCO Project. The

receptors identified for climate change ICCI assessment are outlined in Table 10.4.

10.4.15 The ICCI assessment considers the extent to which climate change exacerbates

effects on PEIR aspect receptors which have already been identified in Chapter 7: Air quality and odour through to Chapter 21.

10.4.16 The following aspects were scoped out of the ICCI assessment: Chapter 16: Major accidents and disasters, as this included consideration of climate change

within its assessment already; and Chapter 19: Transport network users, where

any impacts of climate change to the aspect have been considered as part of the

CCR assessment.

Table 10.4: Aspects scoped into the in-combination climate change impact assessments

Receptor group Receptors included within group

Air quality and odour receptors (Chapter 7) Residential and commercial properties, educational and

medical facilities, businesses.

Biodiversity receptors (Chapter 8) Terrestrial and freshwater habitats, including the species

present within them.

Carbon receptors (Chapter 9) Global atmosphere.

Community receptors (Chapter 11) People and homes, community facilities (including sport

and leisure facilities) and public services, and recreation

and amenity resources.

Human health receptors (Chapter 12) Residents, users and operators of community, open space

and sports facilities, Heathrow colleagues, healthcare

facilities and operators, users of schools and medical and

social care facilities, passengers, road users and visitors to

communities.



Receptor group Receptors included within group

Historic environment receptors (Chapter 13) Cultural heritage assets including but not limited to listed

buildings, scheduled monuments, and registered parks and

gardens.

Land quality receptors (Chapter 14) Surface and groundwater resources, and human

populations within construction sites or at residential,

commercial and industrial land or property.

Landscape and visual receptors (Chapter 15)

Landscape and townscape characteristics and settings,

including residential properties, viewpoints and recreational

routes.

Noise receptors (Chapter 17) Residents in terms of individual dwellings and on a wider

community basis, including community open areas, and

community facilities.

Socio-economics and employment receptors (Chapter 18)

Local businesses and commercial interests, local residents,

and providers of skills, employment and training services,

including schools, higher education facilities and local

training providers.

Waste receptors (Chapter 20) Landfill facilities located off-site.

Water environment receptors (Chapter 21) Groundwater and surface waterbodies, sources of public

water supply and foul drainage infrastructure as defined by

the aspect. Flood risk receptors surrounding the DCO

Project.

10.4.17 The list of receptors is kept under review during the EIA, as more detailed

information is obtained during baseline surveys and other forms of data collection

by other aspects. This will be reflected in the ES.


10.4.18 The receptors in the CCR assessment are the assets shown in Chapter 6, divided

into the activities they support. The asset groups are described in Table 10.5.

Table 10.5: Assets scoped into the climate change resilience assessment

Phase Asset groups

Construction Construction of all built assets, Heathrow colleagues facilities, and access routes to

the Site.

Operation Runways, taxiways and aprons, including operations and aircraft.

New terminal and associated buildings, including airside facilities.

Existing, upgraded and new surface access routes (A Roads and M25), Southern

Road Tunnel, car parking facilities and airside roads.



Phase Asset groups

Drainage and pollution control assets.

Fuel assets.

Flood alleviation and storage infrastructure, fire water and energy storage assets.

On and off-site electrical facilities and utilities corridors.

Airfield telecoms.

Earthworks.

10.4.19 All asset groups have been considered in the scope of the CCR assessment

methodology in Section 10.6 because, based on UKCP18 projections (Met Office,

2018), they are likely to experience effects from climate change.

10.4.20 Only assets developed as part of the DCO Project were considered in the CCR

assessment. A qualitative assessment of the overall resilience to climate change

for the whole of Heathrow Airport will be provided within the Climate Change

Adaptation Plan (CCAP), which will be delivered alongside the ES. This will

include: the adaptive capacity of Heathrow Airport Limited; broader risks from

interdependent infrastructure such as electricity, gas, transport, and

telecommunications networks; effects on destination airports and their networks;

and supply chain risks.

Identification of potential effects

Potential effects (in-combination climate change impact assessment)

10.4.21 Potential effects on climate change ICCI assessment receptors that have been

scoped in for assessment are summarised in Table 10.6.

Table 10.6: Potential effects from in-combination climate change impacts on receptors

Activity Effect Receptor or receptor group

Construction

Increase in noise, dust, odour, NO2 and particulate matter (PM) emissions from construction vehicles and plant equipment.

Increased noise, dust, odour,

NO2 and PM emissions from the

DCO Project have the potential

to affect human health for those

living or working near to the

construction site and/or traffic

routes for construction vehicles.

There is potential for these

effects to be exacerbated by

Residents, users and operators of

community, open space and sports

facilities, Heathrow colleagues,

healthcare facilities and operators, users

of schools and medical and social care

facilities, passengers, road users and

visitors to communities.




severe weather events such as

drought and periods of high

temperatures.

Degradation, disturbance, loss or other changes to habitats or species through construction activities including but not limited to soil compaction, severance of habitats, introduction of pollutants and changes to hydrology.

The DCO Project has the

potential to affect biodiversity.

Severe weather events such as

drought, periods of high

temperatures and floods could

lead to further damage and loss

to habitats or species.

Terrestrial and freshwater habitats,

including the species present within

them.

Displacement, loss or other change to homes, access to services, recreational routes and spaces, transport routes, local environment and economy.

Potential effects on physical and

mental health related to the

displacement of tenants,

changes to social relations,

access to services, open

spaces, active travel routes and

the local environment as a result

of the DCO Project. Severe

weather events including

intense rainfall leading to

flooding, and periods of high

temperatures have the potential

to worsen human health effects

by causing further displacement

or loss and placing more

pressure on health and social

care services.








Increased level and mobilisation of contaminants within the environment.

Potential effects on human

health, groundwater and surface

water resources because of

increased risk of contamination

from the DCO Project. Intense

rainfall and flooding could

exacerbate these effects by

remobilising contaminants within

floodwater, whilst drier, windier

conditions could increase the

migration of windblown dust.

Surface and groundwater resources, and

human populations on the construction

site or at residential, commercial and

industrial land or property.

Disturbance to the setting of a townscape or landscape together with


potential to negatively affect the

character of the local landscape

and townscape and visual

Landscape and townscape

characteristics and setting, residential

properties, viewpoints and recreational

routes.




effects on visual amenity.

receptors. It is possible that

severe weather events such as

drought, or conversely intense

precipitation leading to flooding,

could lead to further

degradation.

Changes and disruptions to local and wider economy and employment.

Potential effects on the

sustainability and viability of

businesses, the economic

activity of residents and wider

economy due to displacement

and changes to the environment

as a result of the DCO Project.

Severe weather events such as

intense rainfall have the

potential to cause further

displacement and disruption

from impacts such as flooding.

Local businesses and commercial

interests, local residents, and providers

of skills, employment and training

services, including schools, higher

education facilities and local training

providers.

Export of construction and demolition waste to hazardous and non-hazardous landfills.

The majority of wastes arising

from the construction phase will

be reused on site. For the

exported waste, not all will be

sent to landfill. However, there

is potential for the waste sent to

landfill to result in decreased

land quality. There is potential

for severe weather events to

exacerbate these negative

effects as high temperatures

and extreme rainfall events can

lead to the production of

leachate.

Third party landfill facility located off-site.

Operation

Increase in noise, dust, odour, NO2 and PM emissions from aircraft operation, airfield activity and vehicles on public highways.

Increased emissions from the

DCO Project have the potential

to affect human health for those

living or working near to the

DCO Project and/or traffic

routes for vehicles. Projected

increases in temperatures and

more frequent dry spells as a

result of climate change have

the potential to further

exacerbate air quality issues by

increasing odour and

tropospheric ozone (O3)











formation from NOx emissions

and PM.

Degradation, disturbance, loss or other changes to habitats or species from changes in the number of vehicles and changes to noise, vibration and light levels amongst others.


potential to affect biodiversity.

Projected increases in

frequency of drought, increase

in temperatures and more

frequent heavy rainfall events

could lead to further damage

and loss to habitats or species

through further increase in toxic

pollutants for example.

Terrestrial and freshwater habitats,

including the species present within

them.

Changes to access to services, recreational routes and spaces, local environment and economy.

Potential effects on physical and

mental health due to additional

noise and pollutant emissions,

changes to safety and access to

services, lifestyles and social

cohesion during the DCO

Project’s operation. Climate

hazards such as severe events

including storms and heatwaves

could further exacerbate these

health effects by placing

additional pressure on services

or preventing active travel, for

example.






facilities, road users and visitors to

communities.

Changes to community facilities (including sports and leisure facilities), community facing business and recreational routes and spaces.

Potential effects on the viability,

sustainability and accessibility of

community facilities which have

been subject to changes in

amenity due to the DCO Project.

Projected increases in climate

hazards such as flooding have

the potential to impact

accessibility and usability of

outdoor recreation facilities for

example. Conversely, extreme

heat has the potential to further

affect the functionality of

community and public services

facilities due to overheating.

Community facilities (including sport and

leisure facilities) and public services, and

recreation and amenity resources.

Loss of flood plain storage and changes to extent of fluvial floodplain, reduced recharge or locally


potential to alter surface water

capacity and groundwater flow

levels during the operational

phase. Projected climate

Groundwater and surface waterbodies.




displaced recharge to groundwater supply due to increased impermeable surface and/or diverted flow.

impacts such as more extreme

and frequent rainfall events

coupled with changes to flood

plain have the potential to

increase the intensity of flood

events. An increase in droughts

as a result of climate change

also has the potential to

exacerbate effects on

groundwater levels.

Construction and operation

Displacement, loss or other change to homes, community facilities (including sports and leisure facilities), community facing businesses and recreational routes and spaces.

Potential effects on the viability,

sustainability and accessibility to

services, changes to the social

cohesion and demographic

profile of communities as a

result of the displacement of

tenants and owners of

residential property due to land

take from the DCO Project.

Projected climate change

impacts such as increased

frequency of severe rainfall

leading to flooding could

exacerbate these effects by

causing further displacement

and disruption.








Material change, damage or loss of significance for the historic environment.

Potential effects for cultural

heritage assets within or

adjacent to the development site

could occur as a result of site

clearance in preparation for

construction and would likely

persist during the operational

phase. It is possible that

increased frequency and

severity of extreme rainfall as a

result of climate change could

cause further damage, such as

water damage, to cultural assets

affected by the DCO Project.

Cultural heritage assets including but not

limited to listed buildings, scheduled

monuments, and registered parks and

gardens.

Disturbance to the setting of a townscape or landscape together with effects on visual amenity.


potential to negatively affect the

character of the local landscape,

townscape and visual receptors.

It is possible that the projected

Landscape and townscape

characteristics and setting, residential

properties, viewpoints and recreational

routes.




increase in drought conditions

and hotter wetter conditions as

a result of climate change could

lead to degradation of

landscapes affected by the DCO

Project.

Changes to ground and surface water flow and quality, increase in water demand and increased discharge of foul drainage.


potential to alter the flow and

quality of surface and

groundwater, and lead to an

increase in water demand.

Projected climate change

impacts, such as more extreme

precipitation events and

increased climate variability,

could exacerbate these effects

through mobilising pollutants

and placing further pressure on

public water supply.

Groundwater and surface waterbodies,

sources of public water supply and foul

drainage infrastructure.

Potential effects (climate change resilience assessment)

10.4.22 Potential effects on climate change CCR assessment receptors that have been

scoped in for assessment are summarised in Table 10.7.

Table 10.7: Potential effects of climate change on asset groups

Phase Effect Asset groups

Construction Extreme weather events or climatic events (such as

strong winds) resulting in effects on the resilience of

construction equipment and resulting in delays to

construction programme and associated costs and/or

unacceptable safety risks.

Extreme weather events or climatic events (such as

heavy rainfall) resulting in effects on the viability of and

access to construction sites (such as heavy rain resulting

in surface water flooding of local roads, sources of power

supply or inundation of construction sites).

Construction of all built

assets, Heathrow colleagues

facilities and access routes

to the Site.

Operation Climate-related hazards such as increased intensity of

precipitation events have the potential to result in

hazardous conditions for operation of vehicles and

planes, slowing operations and causing delays. Increased

intensity of wind events also has the potential to cause

disruption to runway utilisation and schedules.

Runways, taxiways and

aprons, including operations

and aircraft.




Runways and taxiways are also at risk of damage from

climate related hazards. Water damage from increased

precipitation can affect the runway and underground

foundations, structures or services. Increased summer

temperature and increased winter temperature variability

also has the potential to cause damage to the tarmac and

asphalt and effect operations.

Climate-related hazards have the potential to cause

damage to the building and structure fabric. Projected

increases in extreme precipitation events could lead to

water ingress and high wind events could damage the

exterior of buildings or cause failure of equipment.

The facilities required for the building to operate could

also become damaged. Extreme precipitation events

could lead to flooding of the terminal buildings and the

ancillary infrastructure whilst drought could reduce the

potable water availability required for the terminal’s

operation. Overheating from increased summer

temperature due to inadequate heating, ventilation and

air-conditioning (HVAC) systems is also a risk.

New terminal and associated

buildings, including airside

facilities.

Climate change related weather events have the potential

to result in increased risk of surface or structural failure,

warping of slabs, excessive movement at joints and

difficulty in maintaining asphalt surface. There is also the

potential for flooding of road networks and for wind to

create or distribute debris to these areas.

These aspects, when taken individually or in-combination,

could affect the integrity and efficiency of the road and rail

network to different degrees. However, each aspect

ultimately reduces their efficacy as a transport

mechanism.

Upgraded and new surface

access assets (A-roads and

motorway), Southern Road

Tunnel, car parking facilities

and airside roads.

Climate change can exacerbate acute and chronic

impacts on foul, non-potable and surface water

infrastructure. Most notably this relates to the increase in

peak rainfall associated with extreme events and

combined effects of extreme rainfall after cold snaps

leading to de-icer runoff.

Drainage and pollution

control assets.


impacts on fuel and transfer assets due to an increase of

flood risk from fluvial, pluvial or groundwater, increase in

fire risk during hot days, and increased risk in damage to

fuel operations due to lightning strikes.

Fuel assets.




Flood water management infrastructure can be stressed

by exacerbation of flood events under future climates.

Flood alleviation and storage

infrastructure, fire water and

energy storage assets.

Climate change-related weather events have the potential

to damage the over and underground electricity network.

This can be through direct contact (for example, flooding

or wind damage), or through damage to structures or

buildings supporting this network (for example, heat

buckling of HV cables, subsidence).

There is likely to be significant resilience in the electricity

network with alternative supplies available. Multiple

events over a short timescale are likely to have the

greatest impact as these will inhibit any maintenance

activities.

On and off-site electrical

facilities and utilities

corridors.


impacts on fuel storage and transfer assets, particularly

through extreme weather events such as storms.

Airfield telecoms.

Variable groundwater levels affect asset integrity and

could cause subsidence and water ingress damage to

earthworks, underground structures, foundations and

platforms. This has knock-on effects on many of the

assets listed.

Earthworks.

Embedded environmental measures

10.5.1 The DCO Project will consider a number of environmental measures to avoid or

minimise likely significant effects. This approach is described in Chapter 5. Some

of these environmental measures have been embedded into the DCO Project

design. Those embedded environmental measures that influence the assessment

of climate change (ICCI and CCR assessments) are set out in Table 10.8, and the

good practice environmental measures included are in Table 10.9.



Table 10.8: Summary of the embedded environmental measures in the design and how these influence the climate change assessment for both the ICCI and CCR assessments

Receptor / asset group

Changes and effects Embedded environmental measures and influence on assessment

Project-wide. All built assets and relevant environmental receptors.

Operational resilience of the DCO Project reduced over time as conditions increase the likelihood, frequency and/or intensity of climatic and environmental hazards and their subsequent impacts on Heathrow.

The overall approach to ensuring Heathrow is resilient to climate change is set out in the Principles of the Climate Change Adaptation Plan (CCAP), provided in Appendix 10.1. The full CCAP, to be delivered in support of the ES, will set out the requirements for the consideration of climate change throughout the design process, and embedding ongoing climate change resilience following DCO submission, including post-DCO design stages and operational phase. The CCAP will remain live and will undergo further development post-DCO. The CCAP will be in-line with the upcoming ISO 14090: Adaptation to climate change, due for publication in summer 2019. Specific climate change environmental measures embedded into the design for PEIR are:

1. Consideration of climate change in all drainage infrastructure and flood retention

infrastructure. Requirements for consideration of climate change impacts on

groundwater levels, soil moisture content and precipitation are included in the

construction and design of earthworks and structures in-line with the relevant

standards).

2. As set out in Section 4 of Appendix 21.5, an allowance for climate change has

been incorporated into the water treatment element of the airfield drainage

strategy. An appropriate factor of safety has been incorporated into the

preliminary designs to safeguard against adverse changes in climate in the

relatively short term, i.e. 10 to 15 years. For changes in climate beyond the

factor of safety incorporated into the design (likely to be longer term changes in

climate), an adaptive management approach of managed adaptation would be

employed, whereby the water treatment capacity could be improved in future

(perhaps through advances in water treatment technology in the meantime) if

climate change is found to be progressing in a direction that indicated that water

treatment capacity was insufficient. A threshold of Biological Oxygen Demand

(BOD) increase or failure rate will be developed to identify when an adaptation is





required. An adaptive management approach requires a flexible design, such as

one that allows the depth of the gravel substrate to be increased, for example.

The feasibility and practicality of undertaking such an approach will be

considered when designing the co-located water treatment and attenuation

areas.

3. An allowance for climate change has been incorporated into the design of

pollution capture assets (see Section 4 of the Drainage Impact Assessment

(Appendix 21.5)).

4. Appendix 21.4 confirms that the DCO Project design is NPPF compliant

(DCLG, 2019), and therefore considers the impacts of climate change. It

confirms that the proposed design has been developed to avoid areas of known

flood risk wherever possible in line with the sequential risk-based approach

advocated by NPPF (DCLG, 2019). Where there are exceptions to this rule the

PEIR FRA presents a range of potential additional environmental measures to

ensure safe NPPF compliant development.

5. Water efficiencies are built into the DCO Project through Appendix 20.1: Draft resources management plan, Volume 3. This enables an increase in the level

of efficiency in water use per passenger, therefore increases resilience to

drought events.

6. The design standards for buildings will include minimum requirements for

ambient design temperatures, wind pressures and snow loads. The adequacy of

these standards will be assessed throughout the detailed design stage ahead of

submission of the ES.

7. The heating and cooling loads for terminal buildings have been calculated using

relevant future weather files. These have been used in the calculation of the

sizing of the thermal stores.





8. Concepts within relevant international and national guidance for embedding

climate change into technical standards will be embedded within the further

design of all assets. A range of other emerging standards for climate change

adaptation will also be considered in the development of the CCAP through the

design of assets.

Project-wide Disruption as a result of climate change impacts delays to recover and return to normal operations.

Various elements of the Masterplan increase resilience by building redundancy into Heathrow’s operations. These relate to spatial elements of the design rather than the asset design which will be covered in the CCAP. These include:

1. Multiple surface access points from M25 instead of single junction option

2. Inclusion of Southern Road Tunnel

3. Provision of additional power intake from National Grid. Furthermore, the replacement of aging assets with new assets designed with the Climate Change Adaptation Plan in place increases the overall resilience of Heathrow to climate change.

Biodiversity / Landscape and visual

Climate change exacerbates

the effect the DCO Project has

on surrounding biodiversity,

landscape and visual

receptors.

Landscape planting will take into consideration climate change in the selection of appropriate species for planting and through adequate monitoring post-planting. Consideration of climate change in the landscaping design will be incorporated into the Habitat Creation requirements included in the ES.

Biodiversity / Landscape / Green Infrastructure

Climate change exacerbates the effect the DCO Project has on biodiversity and landscape receptors.

Climate change is being built into the environmental measures developed for biodiversity and landscape as they develop. For example, the role of green and blue infrastructure in increasing resilience to climate change will be acknowledged in the landscape design. This includes sustainable water systems, permeable surfacing, shading (of rivers, spaces and buildings) and/or maintenance of connectivity for species, as well as adequate monitoring.

Health Climate change exacerbates the effect the DCO Project has on health.

Potential Urban Heat Island effects are mitigated as far as practicable through the use of appropriate landscaping, planting and building design, including planting large areas of the new airfield with grassland.





Potential overheating effects in replacement buildings are mitigated by all replacement buildings being designed in line with the climate change adaptation requirements of the relevant Local Plans, as defined in Appendix 2.1.

Land quality Climate change exacerbates the effect the DCO Project has on land quality.

The new infrastructure will be designed in accordance with relevant standards which include the mitigation of aggressive ground conditions and geohazards as part of design requirements.

Table 10.9: Summary of the good practice environmental measures and how these influence the climate change assessment


Changes and effects Good practice environmental measures and influence on assessment

Project-wide Operational resilience of the

DCO Project reduced over

time as conditions increase

the likelihood, frequency

and/or intensity of climatic

and environmental hazards

and their subsequent impacts

on Heathrow.

Heathrow has a resilience framework in place to ensure operational resilience to infrastructure failures and environmental hazards, as well as a range of other risks not related to climate change. The framework is developed through a cycle of anticipation, assessment, preparation, review and learning. It is detailed in Chapter 16. The resilience framework includes the procedures to be followed in the event of an incident,

and includes responses to risks outside of Heathrow’s control, such as drought during

construction and operational phases, loss of external utilities or services and the

mismanagement of floodplains by third parties.

Heathrow has incorporated climate change risk assessment into its processes through Climate Change Adaptation Reporting in 2011 and 2016. Monitoring is employed across various assets:

1. Monitoring impact of torrential rain on airside and landside road vehicles and

planes is in place as good practice.

2. Surface condition on extreme temperature days are monitored by airside and

landside operations teams to ensure safe operations.





3. Monitoring of movement of birds across Heathrow Airport has been ongoing

since 2011, with the results fed into the Heathrow Bird Strike Group. Biodiversity

Action plans monitor species on sites. This good practice will follow the

requirements of the CCAP to ensure environmental measures are put in place if

and when required.

4. Monitoring of weather trends to reduce risk from lightning and storms is in place.

Good practice design is employed across various assets as standard:

1. Recent assessments and developments of existing fire main means current

operations sufficient to mitigate risk of increased fires during heatwaves. Good

practice will be extended to the new assets.

2. New underground utilities are not laid at shallow depths to avoid damage due to

temperature extremes during excavations.

3. New de-icing facilities are incorporated into the DCO Project.

4. Lightning protection units installed where risks to sub-components is high.

Redundancy in power intake due to three separate intakes from National Grid

already existing and another including in the DCO Project.

5. All roads, buildings, utilities and airfield assets will be designed for the climatic

conditions experienced at the end of their operational life cycle, using appropriate

design guidance. The design will be progressed between PEIR and ES. In each

case, the replacement and repair cycles of sub-assets will be considered. For

example, for roads, relaying of road surface, or replacement of sub-base will

have substantially different lifespans.

Good practice planning and operational procedures in evidence at Heathrow will be continued

and expanded to include all relevant elements of the DCO Project:





1. Airport fire service embedded in Operational Resilience Plan (Heathrow Airport

Limited, 2015). Good practice of working with fuels and research into spill clean-

up operations in hotter climates and increased intensity of heatwaves.

2. Continued implementation of the Heathrow Winter Resilience Enquiry (2011)

recommendations, including continual development of the snow removal plan.

Construction processes (impact of environmental hazards on process)

Construction delays and

unexpected costs as a result

of severe weather impacts.

The contractors will use a short to medium range weather forecasting service from the Met

Office, or other approved meteorological data and weather forecast provider, to inform short to

medium-term programme management, environmental control and impact mitigation

measures. The contractors will register with the EA’s flood warning service in areas of flood

risk.





A high-level risk assessment of severe weather impacts on the construction process will be

produced by the main contractor to inform mitigations. Any receptors and/or construction-

related operations and activities potentially sensitive to severe weather events should be

considered in the assessment. Climate change projections will be considered in the risk

assessments.





The main contractors’ Environmental Management System (EMS) should consider all

measures deemed necessary and appropriate to manage severe weather events and should

as a minimum cover training of personnel and prevention and monitoring arrangements. As

appropriate, construction method statements should also consider severe weather events

where risks have been identified.

Air Quality and odour receptors

Odours emitted through

evaporation of aviation fuel

and fuel used by Ground

Support Equipment.

Evaporative emissions

increased during hotter

weather.

Monitoring and proposed environmental measures detailed in Chapter 7, such as maintaining the current procedure of a rapid response to fuel spillages.





Historic Environment receptors

Future changes in the

precipitation regime can lead

to changes in the

groundwater level, which

could result in potential

damage to archaeological or

paleoenvironmental remains.

The environmental measures to mitigate potential damage to archaeological or paleoenvironmental remains due changes in groundwater level include: measures to avoid changes to groundwater flows; measures to identify and assess receptors susceptible to groundwater changes; and actions to avoid dewatering as far as practicable. This will be further developed as part of ES.

Land quality receptors

Increase in flooding, high

temperatures, and wetter

conditions may increase

leaching of contaminants

from soils and increase the

amount of landfill leachate

generated.

In the cases where new landfills are created by the DCO Project, these will be compliant with the Landfill Directive (2001) as transposed by The Environmental Permitting (England and Wales) Regulations 2016 (refer to Section 14.10: Assessment of land quality effects).

Community Climate change exacerbates the effect the DCO Project has on surrounding communities.

The design of all replacement outdoor sports facilities will follow guidance set out by Sport England. For example, the Natural Turf for Sport - Design Guidance Note (Sport England, 2011) includes specific reference to climate change. All replacement buildings will be designed in line with the climate change adaptation requirements of the relevant Local Plans, as defined in Appendix 2.1. All surface transport infrastructure will be designed to Environment Agency guidance on Flood risk assessments: climate change allowances and the principles of the Transport Strategy for London.



Methodology for baseline data gathering

10.6.1 Baseline data collection has been undertaken to obtain information over the study

areas described in Section 10.4. This section presents the approach to collecting

baseline data. The current baseline conditions presented in Section 10.9 sets out

data currently available information from the study area.

10.6.2 Baseline data collected through desk studies has been obtained in line with the

policy and legislation set out in Section 10.2. Surveys have not been required

specifically for the ICCI or CCR assessments, although the ICCI assessment relies

upon surveys carried out in other aspects.

Desk study

10.6.3 A summary of the organisations that have supplied supplementary survey data,

together with the nature of that data is outlined in Table 10.10.

Table 10.10: Data sources used to inform the climate change assessment

Organisation Data provided* Data time period Date received

Defra / Met Office: UKCP18

Gridded observation data at both 25km

and 12km spatial resolution.

Baseline time period

(1981 – 2000).

Data was obtained

from the UKCP18

online user interface

in December 2018.


Probabilistic climate change projections

for the UK at 25km spatial resolution. In

line with the ANPS (Department for

Transport, 2018) and NN NPS

(Department for Transport, 2014), data

for the 10%, 50% and 90% probability

levels for the high emissions scenarios

was obtained.

Future time periods.

From 1980 to 2099.

Data was obtained

from the UKCP18


in December 2018.


Regional land projections at 12km

spatial resolution.

Future time periods.

From 1980 to 2080.

Data was obtained

from the UKCP18


and the Centre for

Environmental Data

Analysis (CEDA)

Data Catalogue in

December 2018.


Technical notes, including:

1. UKCP18 Science Overview

report

2. UKCP18 Land projections:

Science report

The technical notes

provide information

on both baseline and

future time periods.

Reports were

downloaded directly

from UKCP18’s

website in December

2018.



Organisation Data provided* Data time period Date received

3. UKCP18 Factsheets.

Met Office Heathrow weather station historical

hourly weather data set (temperature,

rainfall, maximum gust, mean wind

speed, wind direction).

1960 – 2016. August 2017.

Heathrow Report: Climate Change Adaptation

and Resilience Progress Report.

Current and future

climate baseline

information.

Report downloaded

October 2018.

* Refer to Section 10.10 for a full reference of the data and documents downloaded from online websites.

Assessment methodology for PEIR

Assessment methodology evolution

10.7.1 At this stage in the development of the EIA, the DCO Project is still under

development and is the subject of statutory consultation. The likely significant

environmental effects are presented at this preliminary stage. Further, more

detailed assessment work will be undertaken between PEIR and preparation of the

ES on the final DCO Project.

10.7.2 The methodology for the ES may therefore develop further from that used for the

PEIR. Anticipated changes in the assessment methodology are summarised in

Table 10.11, with reasons for any likely amendments detailed.

Table 10.11: Assessment methodology for the PEIR and ES

Effect Assessment methodology used for this PEIR

Assessment methodology to be used for the ES

ICCI The ICCI assessment is reliant on information being gathered and assessed by each aspect. Preliminary survey and modelling information was used to assess climate change exacerbation of impacts for the PEIR.

Supplementary survey data (for example, Biodiversity) and modelling (for example, Flood Risk) mean that the ICCI assessment methodology will be refined from PEIR to ES to incorporate new information.

ICCI and CCR

The climate hazards assessment used the elements of UKCP18 that were available during the preparation of the PEIR.

The climate hazards assessment will be updated to include elements of UKCP18 due in 2019, most notably the 2.2km projections. A more detailed consideration of combinations of tools from UKCP18 will be deployed to cover specific issues where appropriate.

CCR CCR assessment is based on expert judgement from design leads using the UKCP18 data.

Operational performance statistics will be mapped against weather and climate information to increase understanding of how



Effect Assessment methodology used for this PEIR

Assessment methodology to be used for the ES

existing assets and systems respond to stresses, therefore enriching the evidence base.

CCR CCR assessment based on core UKCP18 data.

CCR assessment will incorporate more radical changes in climate using sensitivity analyses where appropriate.

10.7.3 The generic project-wide approach to the assessment methodology is set out in

Chapter 5. This has informed the approach used in the assessments of climate

change in this chapter.

10.7.4 The methodology outlined in this section is split into the climate hazards

assessment, the ICCI assessment and CCR assessment. The climate hazards

assessment is required by both the ICCI and CCR assessments and so is

described separately.

Climate hazards assessment

10.7.5 Both the ICCI and CCR assessments are reliant on an understanding of the

climate hazards that have the potential to affect the Site. The changes in climate

variables have been assessed for the future years 2030s (2020 – 2039), 2050s

(2040 – 2059), 2080s (2070 – 2089) and 2099 for the high emissions scenario,

and are therefore in line with the ANPS (Department for Transport, 2018) and NN

NPS (Department for Transport, 2014). Section 10.4 provides more detail on the

selection of assessment years.

10.7.6 A climate hazard can be defined as a weather or climate event that has the

potential to do harm to an environmental or community receptor, or the built

infrastructure. Reduced summer precipitation is an example of a climate hazard.

10.7.7 A derived climate hazard is a weather or climate related event that has the

potential to occur as a result of a climate hazard but is not directly provided by

UKCP18, for example, reduced summer precipitation leading to drought

conditions.

Climate variables

10.7.8 Where data is available, climate variables for the current baseline and future

climate conditions have been downloaded directly from UKCP18 to inform the

assessments within this chapter. However, where information is not directly

available, hazards have been assessed using either a combination of variables

and/or sources of data and information outside of UKCP18, or from technical

guidance provided alongside UKCP18 (Met Office, 2018). For these derived



hazards, there is no data relating to the probabilistic level of likelihood and so

there is more subjectivity over the likelihood of occurrence.

10.7.9 Descriptions of the climate variables and derived hazards assessed in the climate

hazard assessment are listed in Table 10.12 and Table 10.13.

Table 10.12: Climate variables that have been assessed in the climate hazards assessment

Climate variable Characteristic Description

Temperature Mean winter

temperature

Mean daily temperature in December, January and February

Mean summer

temperature

Mean daily temperature in June, July and August

Number of hot

days

Number of days in a year with daily maximum temperature higher

than 25°C

Number of frost

days

Number of days in a year with daily minimum temperature equal to

or lower than 0°C

Precipitation Mean winter

precipitation

Mean daily precipitation in December, January and February

Mean summer

precipitation

Mean daily precipitation in June, July and August

Peak rainfall Annual number of days per year when precipitation is greater than

25mm per day (Met Office definition of ‘heavy rain’)

Dry spells Number of periods in a year with 10 days or more with no

precipitation

Wind Mean winter

wind speeds

Mean daily wind speeds in December, January and February

Mean summer

wind speeds

Mean daily wind speeds in June, July and August

Strong winds Wind speeds well above average which can cause damage to

receptors and/or assets. Average daily winds speed above 10 m/s

have been considered.

Lightning Lightning

occurrence

Number of lightning days in a year

Fog Winter foggy

days

Number of days with fog (visibility below 1000m) in December,

January and February

Summer foggy

days

Number of days with fog (visibility below 1000m) in June, July and

August



Table 10.13: Derived hazards that have been assessed in the climate hazards assessment

Derived hazards Description

Flooding Fluvial flooding, pluvial flooding and groundwater flooding

Droughts Prolonged periods with low rainfall, defined as 10 or more days with rainfall lower than

0.1mm

Fire Naturally occurring wildfires due to climate and environmental conditions (not

intentionally started)

Soil moisture deficit

Depth of rainfall needed to bring the soil moisture content back to field capacity

Heatwaves Defined as 2 days with maximum temperature higher than 29°C and minimum

temperature higher than 15°C

Snow and ice Accumulation of snow and ice during cold weather spells

Storms Active area of low pressure with associated strong winds and precipitation

Extreme rainfall during cold snaps

Peak rainfall (greater than 25mm per day) occurring during cold snap periods

Likelihood

10.7.10 The likelihood of a hazard has been estimated based on the probability of a

specific climate variable being exceeded under future climate change conditions. It

does not give an indication of the magnitude of change. The probability of

exceedance can represent either an intensity value (used mainly for changes in

mean conditions) or a frequency of occurrence (mainly used for more extreme

characteristics). The criteria to assess the level of likelihood are shown in Table 10.14. These are aligned with the levels of likelihood defined in UKCP18 (Met

Office, 2018).

Table 10.14: Criteria to assess likelihood of hazard (based upon UKCP18)

Level of likelihood

Very unlikely Unlikely Possible Likely Very likely

Likelihood of occurrence

<10%

probability

<33%

probability

33% to 66%

probability

>66%

probability

>90%

probability

10.7.11 The approach used to assess likelihood depends on whether probabilistic

projections or quantitative estimates are available for the climate variable of

interest. Probabilistic projections refer to changes in future climate based on an

assessment of climate model uncertainties. Quantitative estimates refer to the



outputs of 12 high-resolution climate futures from climate models at 12km spatial

resolution.

10.7.12 Three approaches have been defined to assess likelihood of hazards. The choice

of approach is dependent on the data available. These are described, in order of

preference and data availability requirements, as follows:

Use of probabilistic projections. This approach is used when probabilistic

projections are available from UKCP18 (Met Office, 2018). In this approach,

the likelihood of increased severity has been estimated using these projections.

The values obtained from UKCP18 (Met Office, 2018) are the anomaly values

(for instance, magnitude of change for each probability level compared to

current baseline value). Hence, the threshold to estimate likelihood has been

set to the current baseline value of the climate variable

Use of land regional projections. This approach is used when probabilistic

projections are not available but results from the regional land projections are

available. The likelihood of the hazard is inferred from the magnitude of change

obtained from the regional land projections, using expert judgement and

available literature. The mean of all the climate models (in 12 models) in the

regional land projections has been used to estimate the future value for the

climate variable. The threshold to estimate the likelihood of exceedance has

been set to the current baseline value. As per the future climate values, the

current baseline value has been estimated using mean values obtained from all

models

Use of UKCP18 technical notes and additional literature. This approach is

used when probabilistic projections and land projections, are not available. In

this approach UKCP18 technical notes and additional local planning policy

literature (listed in Appendix 2.1) have been reviewed to provide insight on the

potential direction of change. The likelihood of a threshold being exceeded has

been inferred using UKCP18 technical notes and other sources of technical

information.

10.7.13 Probabilistic and land regional projections are not available to assess derived

hazards. Hence, the use of UKCP18 technical notes and additional literature

(approach 3 listed above), has been applied to the derived hazards. Due to the

lack of direct climate change projections, the results are presented as a direction

of change (increase, decrease or possible increase) rather than as a likelihood

level.

10.7.14 The regional projections available in UKCP18 (Met Office, 2018) cover the time

period 1980 to 2080, rather than 1980 to 2099 as for the probabilistic and the

global projections. For this reason, the twenty-year period covering 2060 to 2079

available from this dataset, has been used as a surrogate for the 2080s period.



10.7.15 For each climate variable and derived hazard, the level of confidence (categorised

into low, medium and high) in the likelihood estimate has been determined by

following the approach described above and then applying expert judgement. In

the instances where probabilistic values are available, the level of confidence has

been set to high. Where results from the UKCP18 (Met Office, 2018) regional

projections were available, the level was set to medium. In all other cases the level

of confidence was set to low.

10.7.16 The results of the climate hazard assessment are described in Section 10.9.

Assumption and limitations related to climate projections

10.7.17 A limitation of the climate change projections data arises from the absence of

probabilistic projections for all relevant climate variables and hazards. The level of

information (for example, quantitative data, publications) also varies depending on

the climate variable. The existence of probabilistic projections and available

information have been used to provide an estimate on the level of confidence in

the likelihood and direction of changes in climate.

10.7.18 The time period covered by the regional projections is 1980 to 2080, and not 1980

to 2099, which is a limitation in the analysis of climate parameters for which

probabilistic projections are not available. The 12km spatial resolution regional

projections are only available from 1980 – 2080. This is because the regional

projections at 12km spatial resolution were originally run as part of UKCP18 (Met

Office, 2018) to drive the 2.2km spatial resolution model. This latter model

required data only for 1980-2000, 2020-2040 and 2060-2080.

10.7.19 Several products from UKCP18 were not available at the time of preparation of the

PEIR. In those cases, alternative data products have been used to complete the

climate hazard assessment. The currently unavailable products and the

alternatives used at this stage are:

1. Regional land projections at 2.2km spatial resolution for all climate variables

are not currently available in UKCP18 (Met Office, 2018). These are unlikely to

be available until June 2019. Regional land projections at 12km have therefore

been used in this PEIR

2. Information on climate change effects on lightning and fog is not currently

available in UKCP18 (Met Office, 2018). The information available from

UKCP09 has therefore been used in this PEIR. If further information becomes

available later, this will be considered in the ES.

10.7.20 Further analysis of UKCP18, including combining different tools to gain an

increased richness of information, will be carried out for the ES where appropriate.




Introduction

10.7.21 The ICCI assessment assesses the extent to which climate change exacerbates

an effect on an environmental receptor listed in Table 10.4.

10.7.22 The ICCI assessment methodology has been developed in-line with the Institute of

Environmental Management and Assessment (IEMA) – ’Environmental Impact

Assessment Guide to Climate Change Resilience and Adaptation’ (IEMA, 2015).

10.7.23 This section describes the key terms used within the ICCI assessment and the

methodology followed.

Key terms

10.7.24 The following key terms and definitions relating to the ICCI assessment have been

used:

1. A climate hazard is a weather or climate related event that has the potential to

do harm to an environmental or community receptor or resource considered in

the ICCI assessment. An example of a climate hazard is reduced summer

precipitation

2. A climate impact can be any type of damage (to the infrastructure or assets, or

the case of ICCI to the effects of the DCO Project) as a result of a climate

hazard affecting the ability of the receptor or resource to maintain its function or

purpose. A climate impact can be direct, for example drying out of soils, or

indirect, for example, limited tree growth because of soil moisture deficit

3. An ICCI results when a climate change impact increases or decreases the

effect of the DCO Project on an environmental receptor. For example, the

biodiversity aspect may identify an effect on an environmental receptor (such as

severance of semi-natural woodland) arising from the DCO Project. In addition,

the climate hazard (for example, drought) will lead to a climate change impact

(for example, reduced vegetation growth), the ICCI is the exacerbation of the

original effect identified by the environmental aspect. Any environmental

measure in place to reduce the effect of the severance would therefore need to

also consider the future climate conditions

4. The effect of an ICCI is any change to the severity of the effect originally

identified by the environmental aspect due to an ICCI

5. Aspects use different criteria for determining significance, so there is no single

approach to determining the significance of an ICCI. The effect of an ICCI is

therefore considered significant if:



i. An effect which was previously not significant becomes significant

against the significance criteria used by the aspect, due to climate

change (e.g. an increase in consequence of effect or an increase in

scale of change) or

ii. An existing significant effect is exacerbated, against the significance

criteria used by the aspect, due to climate change (e.g. a further

increase in consequence of effect or a further increase in scale of

change).

If an effect was previously not significant and any exacerbation by climate

change does not change this, the ICCI effect is not significant. Professional

judgement of the climate change experts and experts from the relevant aspect

are used to assess whether the effect of the ICCI is significant.

Methodological approach to the In-combination Climate Change Impact assessment

10.7.25 The methodological approach is described in Graphic 10.2.



Graphic 10.2: Methodological approach to in-combination climate change impact assessment



Phase 1 – assessment of in-combination climate change impact likelihood

10.7.26 Phase 1 aims to screen out any ICCIs that are considered too unlikely to occur to

warrant further assessment.

10.7.27 The assessment considered the effects already identified by environmental

aspects based upon their own assessment methodologies. It also identified any

embedded environmental measures proposed by the environmental aspect and

the engineering and design teams.

10.7.28 A longlist of potential ICCIs was formed based on:

1. The initial assessment results from all aspects’ assessments, based on their

own assessment methodologies

2. A literature review of recent guidance, science and policy relating to climate

change impacts on the relevant receptors.

10.7.29 The likelihood of each potential ICCI occurring was then assessed using expert

judgement based on two factors:

1. The likelihood of the climate impact occurring, based on the climate hazard

assessment

2. The likelihood of the climate impact interacting with an effect as identified by an

aspect. This was assessed based on the strength of evidence in the literature

review. This included the UK Climate Change Risk Assessment (CCRA) (Defra,

2017a), and the expert judgement of the climate and environmental specialists

involved in the DCO Project. In assessing this likelihood, the embedded

environmental measures described in Section 10.5 were considered, as well as

embedded environmental measures identified in each aspect chapter.

10.7.30 Due to the uncertainties involved, the potential ICCIs were assessed to be either

‘likely’ or ‘unlikely’. Where the ICCI was deemed ‘unlikely’, either due to the climate

impact being unlikely to occur or there being a weak link between the climate

impact and the effect on a receptor, it was not taken forward to Phase 2.

10.7.31 The output of Phase 1 is a full list of likely ICCIs, which are included in Table 10.20.

Phase 2 – assessment of consequence and significance

10.7.32 Phase 2 assessed the consequence of the likely ICCIs identified in Phase 1, thus

enabling a determination of significance for each.

10.7.33 The assessment of significance was carried out by the climate change aspect and

environmental specialists from the relevant aspects, working in an integrated



manner to provide a qualitative assessment of consequence and therefore

significance of the ICCI.

10.7.34 An ICCI effect has been considered significant if:

1. An effect which was previously not significant becomes significant against the

significance criteria used by the aspect due to climate change (e.g. an increase

in consequence of effect or an increase in scale of change) or

2. An existing significant effect is exacerbated against the significance criteria

used by the aspect due to climate change (e.g. a further increase to in

consequence of effect or a further increase in scale of change).

10.7.35 The spatial extent, duration and time horizon of the climate change impact were

considered when determining whether the effect of the DCO Project on the

environmental receptor in question would be greater due to the impact of climate

change.

10.7.36 Embedded environmental measures have been included within the assessments

of significance presented. Any additional environmental measures for residual

effects will be incorporated into the CCAP if required.

10.7.37 The exception to the approach described here is the assessment for flood risk and

drainage design. A separate FRA has been carried out (Appendix 21.4), which is

quantitative, and follows current Environment Agency guidance on climate change

allowances for increases in peak river flow, but not for other flood risk sources at

the PEIR stage. These other flood risk sources will be considered for the ES.


10.7.38 The CCR assessment used a risk-based approach to evaluate whether the climate

resilience of the DCO Project is affected by climate change (for instance, by the

projected change in climate variables described in Section 10.10) within the

anticipated lifetime of its assets and overall operation (considered to be perpetual).

This meets the requirements of the ANPS (Department for Transport, 2018) and

the NN NPS (Department for Transport, 2014). It also satisfies Heathrow’s own

commitments to ’work with our airport partners to ensure that the airport plays its

role in respecting environmental limits, and adapting to the effects of a changing

climate’ (Heathrow Airport Limited, 2019) and ’following Government approval, the

third runway design will be progressed and refined…climate change adaptation

and resilience will be included as key design principles’ (Heathrow Airport Limited,

2016).

10.7.39 Only assets developed as part of the DCO Project were considered in the CCR

assessment. A qualitative assessment of the overall resilience to climate change

of the three runway airport will be provided within the CCAP, delivered alongside



the ES. This will include the adaptive capacity of Heathrow and broader risks from

interdependent infrastructure such as electricity, gas, transport and

telecommunications networks, as well as effects on destination airports and their

networks.

Key terms

10.7.40 The following key terms and definitions relating to the CCR assessment were

used; these are in-line with those used in the UK Climate Change Risk

Assessment 2017 (Defra, 2017a), but have been adapted to suit the CCR

assessment within an EIA context:

1. A climate hazard is a weather or climate related event, which has the potential

to do harm to the infrastructure and assets associated with the DCO Project

considered in the CCR assessment. An example of a climate hazard is a high

precipitation event

2. Vulnerability is the propensity or predisposition of a receptor to be negatively

affected by climate change

3. A climate impact can be any type of damage to the infrastructure or assets or

interference with their ability to operate as a result of a climate hazard – an

impact can be either direct, for example flooding of the infrastructure or assets,

or indirect, for example heat exhaustion of workers

4. A consequence is any negative or positive effect on the DCO Project as a

result of an impact. It can be defined in terms of safety, cost, journey times

and/or public perception

5. Risk combines the likelihood of an impact resulting from a climate hazard on

infrastructure, assets and operations, taking into account environmental

measures, and the consequence resulting from the impact if it occurs.

10.7.41 An example of the resilience of the DCO Project being affected by climate change

is the potential overheating of buildings arising from an increase in high

temperatures. In this example, vulnerability of the asset relates to its initial design

specification. The hazard is the high temperature, and the impact is the

overheating in buildings. One potential consequence could be either financial

losses or delays caused by reduced Heathrow colleague productivity. The level of

risk to the DCO Project is then estimated as the combination of the likelihood of

overheating in buildings, due to an increase in temperature, and the qualitative

magnitude of its consequence. Should the level of risk warrant it, risk management

measures would be put in place through the provision of environmental measures.



Methodological approach to the Climate Change Resilience assessment

10.7.42 The risk framework used to assess the resilience of the DCO Project to climate

change is shown in Graphic 10.3.

Graphic 10.3: Risk framework for climate change resilience assessment

10.7.43 The risk framework assessment consists of 10 stages:

1. Compile inventory of assets. The assets and asset groups included within

the DCO Project were organised into activity types and listed. Both

construction and operational phases of the DCO Project were considered



2. Determine criticality of assets. Based on expert opinion and literature, the

extent to which the asset is critical to the functionality of Heathrow airport

was described as low, medium or high. Assets with low criticality were not

considered further. Criticality categorisations were informed by the existing

airport asset prioritisation approaches

3. Compile climate information. Climate information was compiled as per

the climate hazards assessment methodology

4. Climate hazard assessment. The climate hazards assessment, for which

a methodology is provided separately in Section 10.7, was used. Very

unlikely or unlikely hazards were not considered further

5. Vulnerable assets. Assets that meet the criteria in stages 2 and 4 are

considered vulnerable, and are therefore taken forward for further

assessment

6. Likelihood of climate change impact. The likelihood of each impact was

determined based on the definitions in Table 10.15

Table 10.15: Criteria to assess likelihood of climate change impact

Level of likelihood Definition of likelihood

Very unlikely (1) Impact is highly improbable to occur during the operational phases of the

assets or systems, or the construction phase.

Unlikely (2) Impact is not expected to occur during the operational phases of the assets

or systems, or the construction phase.

As likely as not (3) Impact may occur during the operational phases of the assets or systems,

or the construction phase.

Likely (4) Impact is expected to occur during the lifespan of the assets or systems, or

the construction phase.

Very likely (5) Impact is highly probable to occur during the lifetime of assets or systems,

or the construction phase.

7. Consequence of climate change impact. The consequence of each

impact was determined based on the definitions in Table 10.16, and

Heathrow’s Operational Resilience Requirement ’to secure the availability

and continuity of airport operation services, particularly in times of

disruption, to further the interests of users of air transport services in

accordance with best practice and in a timely efficient and economical

manner’ (Heathrow Airport Limited, 2016)



Table 10.16: Criteria used to assess consequence of a climate change impact

Level Safety Cost Passenger Journey Times

Public Perception

Very low (1) Minor harm or near

miss <£5m

Minor delays <1

hour

Short-term negative

local stakeholder

reaction.

Low (2)

Lost time to injury or

medical treatment

required, short term

impact on persons

affected

£5m to £25m Substantial delays

>1 hour

Negative local media

reports over

sustained period;

localised stakeholder

concern.

Medium (3)

Long-term injury or

illness, prolonged

hospitalisation or

inability to work

£25m to

£100m

Major delays and

cancellations <1

day

Significant local or

regional reports

including social

media; national

media interest

creating public

concern.

High (4) Single fatality or

multiple long-term

injuries

£100m to

£250m Major cancellations

1-14 days

Extensive prolonged

negative national

reporting and public

disputes with key

stakeholders.

Very high (5) Multiple fatalities >£250m Severe

cancellations >2

weeks

Extensive and

prolonged negative

reporting nationally

and or public

disputes with key

stakeholders.

8. Integrated risk. The risk for each impact was determined based on the

matrix shown in Table 10.17. Risk appraisal was carried out with relevant

asset owners and relevant design teams using a workshop approach to

ensure agreement on risk categorisation



Table 10.17: Criteria used to assess risk levels for the climate change resilience assessment

Con

sequ

ence

Very high (5)

Low Medium High Very high Very high

High (4) Low Low High High Very high

Medium (3) Low Low Medium High High

Low (2) Very low Very low Low Medium Medium

Very low (1) Very low Very low Low Low Low

Very unlikely (1)

Unlikely (2) As likely as not (3)

Likely (4) Very likely (5)

Likelihood of the impact occurring (a climate hazard having an impact)

9. Significance assessment. Risks assessed to be ‘medium’, ‘high’ or ‘very

high’ were considered to result in significant CCR effects (and are

demarcated in purple in Table 10.17).

10. Mitigation. Additional environmental measures were developed for any

significant CCR effects to mitigate risk. Where environmental measures

were required, stages 6 to 9 of the risk framework were repeated to

ascertain significance with additional environmental measures in place.

Refer to Section 10.5 for a description of the environmental measures

used.

10.7.44 In relation to flood risk and drainage design, it should be noted that under the

ANPS (Department for Transport, 2018) and NN NPS (Department for Transport,

2014), the NPPF planning requirements (DCLG, 2019) and Environment Agency

design guidance relating to climate change apply (Environment Agency, 2016).

Therefore, a separate FRA and Drainage Impact Assessment were conducted

(Appendix 21.4 and Appendix 21.5), which include an assessment of climate

change effects on flood risk. The results of these assessments were considered by

the climate change aspect leads, the relevant DCO Project engineering and

design teams, and the water environment aspect leads, as part of the overall CCR

assessment.

Assumptions and limitations of this PEIR

10.8.1 The assumptions and limitations listed in this section of the PEIR apply to both the

CCR and ICCI assessments.

10.8.2 In relation to groundwater flood risk, how future changes in recharge may affect

groundwater levels and flow direction, and the interaction with both sub-surface

infrastructure and the land surface has not been considered in the groundwater



modelling scenario assessment (Appendix 21.2: Groundwater modelling scenario assessment, Volume 3). This will be incorporated into the groundwater

assessment prepared for the ES.

10.8.3 The resilience of critical assets to more radical changes in climate beyond those in

the latest climate change projections has not been considered at this stage. This

will be incorporated into the ES, when sensitivity assessments will be available.

10.8.4 Only the principles of the environmental measures within the CCAP have been

produced for the PEIR. The exact nature of the environmental measures, and how

that fits into a coherent plan for delivery, will be described in the ES and developed

post-DCO. This does not affect the robustness of the PEIR assessment as the

requisite commitments for considering climate change throughout the design

process have been made.

10.8.5 All existing assets are assumed to be maintained in-line with the conclusions of

the Heathrow Climate Change Adaptation Report 2016 and are therefore not

assessed here. The CCAP, to be produced with the ES, will cover the process for

ensuring resilience of all assets (existing and newly built for the DCO Project). This

will therefore supersede the existing Heathrow Climate Change Adaptation Report

2016.

10.8.6 ‘More radical’ changes in climate, which are unlikely but possible, have not been

considered at this stage in the hazard assessment. They will be considered in the

preparation of the ES using UKCP18 data (Met Office, 2018) from the regional

projections and probabilistic projections. The most conservative value obtained

from either the group of climate models used in the regional land projections (12

models in total) or the probabilistic projections for the relevant climate variable will

be selected for high temperatures, high rainfall events and dry spells. The ES will

therefore be in-line with the requirements in the ANPS (Department for Transport,

2018) and NN NPS (Department for Transport, 2014) for considering more radical

changes in climate.

10.8.7 These limitations do not affect the robustness of the climate change assessment

at PEIR stage.

Overall baseline

Current baseline

Introduction

10.9.1 For the ICCI assessment, the current baseline for the receptors relevant to each

aspect listed in Table 10.4 is that described in the respective aspect chapters.



10.9.2 The CCR assessment is a risk assessment of the DCO Project in the future

climate conditions and does not describe the change in risk from a baseline

scenario to the three runway future scenario. However, it is useful to understand

the current conditions at the Airport for comparison with the future projections,

which are outlined in Section 10.10.

Current climate baseline

10.9.3 The period 1981 to 2000 has been used to define the baseline climate conditions

in order to compare current and future climate. This is aligned with the time period

mainly used in UKCP18 (Met Office, 2018) for describing climate changes in the

UK.

10.9.4 Heathrow has a temperate marine climate with mild damp winters and warm, drier,

sunnier summers, similar to much of the southern British Isles. Close to

continental Europe, it can be exposed to continental weather influences that bring

cold spells in winter and hot, humid weather in summer.

10.9.5 Current climate conditions at Heathrow Airport can be summarised as:

1. Winter temperatures largely remain at or above freezing, with mean daytime

highs above 4.9°C

2. Summers are generally warm with mean daily temperatures above 16°C.

Warm weather is expected between May and September. On average,

Heathrow experiences more than twenty days above 25°C per year

3. Temperatures at Heathrow Airport can be up to 5°C higher than those

experienced in the surrounding countryside because of the London Urban Heat

Island (UHI) effect (Hacker et. al., 2012; Greater London Authority, 2006)

4. Most precipitation during winter months falls as rain rather than snow. Snowfall

at Heathrow has been uncommon in recent years due to the UHI effect and the

overall increase in mean temperatures

5. During summer months, rainfall is relatively low but often falls in heavy

convective events

6. The prevailing wind direction is south-west and mean wind speed is higher in

the winter months

7. The number of days with lightning per season does not exceed 10 days.

Summer is the season when most lightning occurs, and winter is the season

with least lightning

8. The physical location of Heathrow Airport (low-lying and relatively close to the

River Thames) means that it is prone to fog, particularly freezing fog during



autumn and winter months. There are on average five foggy days during the

winter season and three foggy days every ten years during summer.

Future baseline

10.9.6 For the ICCI assessment, the future baseline for the receptors relevant to each

aspect is that described in the respective chapters.

10.9.7 The future climate conditions that are of relevance for both the ICCI and CCR

assessments are the climate change projections as described in the hazard

assessment (Section 10.10).

Assessment of climate change effects

Introduction

10.10.1 The assessment of the effects of climate change on the DCO Project is described

for the construction and operational phases of the DCO Project.

10.10.2 The assessments follow the methodologies set out in Graphic 10.2 and Graphic 10.3. Both the ICCI and CCR assessments require an assessment of the climate

hazards projected to impact the DCO Project over its construction and operational

phases. The climate hazard assessment is presented first.

Hazard assessment

10.10.3 Section 10.7 describes the methodology followed to estimate likelihood of a

climate hazard under future climate conditions.

10.10.4 The likelihood of change in climate variables under climate change conditions is

shown in Table 10.18. The table includes the direction of change in the climate

variable that could lead to an increased severity of a hazard, which can cause a

negative impact on an asset or receptor. For example, an increase in summer

mean temperature could lead to future high temperatures which cause damage to

roads, runways and taxiway surfaces. The table also includes the current baseline

value, the qualitative level of confidence and data source.



Table 10.18: Future changes in climate variables for 2030s, 2050s, 2080s and 2099

Climate variable

Characteristic Current baseline

value

Direction of change for increased severity of hazard

2030s likelihood

2050s likelihood

2080s likelihood

2099 likelihood

Qualitative level of confidence

Data source

Temperature

Mean winter

temperature 4.9°C

Decrease in

intensity

Very

unlikely

Very

unlikely Very unlikely Very unlikely High

UKCP18

Probabilistic

projections

Mean summer

temperature 16.9°C

Increase in

intensity Very likely Very likely Very likely Very likely High

UKCP18

Probabilistic

projections

Number of hot

days, defined

as days with

daily maximum

temperature

higher than

25°C

24 days/year Increase in

frequency Likely Very likely Very likely*

Data not

available** Medium

UKCP18

Regional

land

projections

(12km)

Number of

frost days,

defined as

days with daily

minimum

temperature

equal or lower

than 0°C

36 days/year Increase in

frequency

Very

unlikely

Very

unlikely

Very

unlikely*

Data not

available** Medium

UKCP18

Regional

land

projections

(12km)

Precipitation Mean winter 1.84

mm/day

Increase in

intensity Likely Likely Likely Likely High

UKCP18

Probabilistic

projections



Climate variable


value


2030s likelihood

2050s likelihood

2080s likelihood

2099 likelihood


Data source

Mean summer 1.61

mm/day

Decrease in

intensity Likely Likely Likely Likely High

UKCP18

Probabilistic

projections

Annual

number of

days per year

when

precipitation is

greater than

25mm per day

(Met Office

definition of

‘heavy rain’)

1.5 days/year Increase in

frequency Possible Likely Likely*

Data not

available** Medium

UKCP18

Regional

land

projections

(12 km)

Dry spells (10

days or more

with no

precipitation)

5.8

spells/year

Increase in

frequency Possible Likely Very likely*

Data not

available** Medium

UKCP18

Regional

land

projections

(12km)

Wind

Mean winter

wind speeds 3.7m/s

Increase in

intensity

Very

unlikely

Very

unlikely Very unlikely

Data not

available** Low

UKCP18

Regional

land

projections

(12km)

Mean summer

wind speeds 3.0 m/s

Increase in

intensity

Very

unlikely

Very

unlikely Very unlikely

Data not

available** Low

UKCP18

Regional

land



Climate variable


value


2030s likelihood

2050s likelihood

2080s likelihood

2099 likelihood


Data source

projections

(12km)

Strong winds,

including

storms

- Increase in

frequency Possible Possible Possible*

Data not

available** Low

UKCP18

Regional

land

projections

(12km)

Lightning Lightning

storm

occurrence

Less than 10

days per

season

Increase in

frequency Possible Possible Possible Possible Low UKCP09

Fog

Winter foggy

days

5

days/season

Increase in

frequency Possible Possible Possible Possible Low UKCP09

Summer foggy

days

0.3

days/season

Increase in

frequency

Very

unlikely

Very

unlikely Very unlikely Very unlikely Low UKCP09

Specific humidity

Winter mean

humidity 83.0% Increase in

intensity Likely Very likely Very likely Very likely High

UKCP18

Probabilistic

projections

Summer mean

humidity 72.1% Increase in

intensity Likely Likely Very likely Very likely High

UKCP18

Probabilistic

projections

* These estimates are based on regional projections from UKCP18 for the period 2060 to 2079, which are the last 20 years for which there is data

available from this product

**Data for the year 2099 is only available for probabilistic projections. For land projections data is available up to 2080.



10.10.5 Table 10.19 shows the direction of change in the occurrence of the derived

hazards. Due to the lack of quantitative estimates, Table 10.19 indicates whether

an increase, decrease or no change is anticipated for the hazard under future

climate change conditions. Information on climate change effects on groundwater

flooding are not included in Table 10.19. This will be incorporated into the ES (see

assumption in Section 10.8).

Table 10.19: Direction of change in hazards for 2020s, 2050s and 2080s

Hazard 2020s 2050s 2080s Qualitative level of confidence

Occurrence of fluvial flood Increase Increase Increase High

Occurrence of pluvial flood Increase Increase Increase High

Occurrence of droughts

Possible

increase Increase Increase Medium

Occurrence of fire Possible

increase

Possible

increase Increase Low

Occurrence of soil moisture deficit

Possible

increase

Possible

increase

Possible

increase Low

Occurrence of heatwaves Increase Increase Increase High

Occurrence of snow and ice Decrease Decrease Decrease Medium

Occurrence of storms

Possible

increase

Possible

increase

Possible

increase Low

Occurrence of extreme rainfall during cold snaps

Decrease Decrease Decrease Low

10.10.6 The key results of the climate hazard assessment presented in Table 10.18 and

Table 10.19 can be summarised as:

1. Winter temperatures are very unlikely to decrease in the future. Winter

temperatures are projected to largely increase from the baseline to 2020 to

2099. By the 2080s the mean winter temperature is expected to increase by

3°C (50th percentile and RCP8.5) by the 2080s and up to 4.1°C by 2099. The

number of frost days (daily minimum temperature equal or lower than 0°C) is

expected to reduce by around 88% by the 2080s from the current baseline of

36 days per year



2. Summer temperatures are very likely to increase in the future, with an

expected increase of around 4.8°C by the 2080s (50th percentile and RCP8.5)

and up to 7.1°C by 2099. The number of hot days at Heathrow (daily maximum

temperature higher than 25°C) are projected to increase threefold in the 2080s

from the current baseline of 24 days per year

3. Summer precipitation is likely to decrease in the future whilst winter

precipitation is likely to increase. Summer precipitation is projected to decrease

up to 34% by the 2080s (50th percentile and RCP8.5). Winter precipitation is

projected to increase up to 21% by the 2080s (50th percentile and RCP8.5)

4. Extreme rainfall events are expected to become more frequent. By the 2080s,

the number of heavy rainfall days (days per year when precipitation is greater

than 25mm per day) is likely to increase by around 60%. Similarly, the number

of dry spells (ten days or more with no precipitation) is very likely to increase

(double number of dry spells in the future when compared to baseline)

5. There is no clear trend in the projections for mean wind speeds. It is

considered very unlikely that large changes will be observed in the future in

both winter and summer wind speeds. An increase of 2.0% is anticipated for

winter mean wind speed and a decrease of 4.3% in summer mean wind speed

by the 2080s. It is considered possible that there will be an increase in the

frequency of strong winds, including storms, in the future.


10.10.7 The following section describes the key findings from the ICCI assessment for

each aspect. Table 10.20 summarises the findings of the Phase 1 and 2 ICCI

assessment.

10.10.8 Phase 1 identified all potential ICCIs and assessed their likelihood. Only ICCIs

considered likely were carried forward to Phase 2, where the consequence and

significance of the ICCI effect was assessed.

10.10.9 Due to the volume of potential ICCIs identified, Table 10.20 only includes ICCIs

considered likely, as assessed in Phase 2.



Table 10.20: In- combination Climate Change impact assessment results

Aspect Phase 1 Phase 2

Climate hazard Likely ICCIs identified Consequence of ICCIs considering

embedded environmental measures/good practice

Significance of ICCI effects

Air quality and odour (Chapter 7)

Increased

number of hot

days; increase

of droughts

Increased dust

production during

construction due to

extended dry spells

During the construction phase, extended dry spells may cause

increased dust production. This consequence is minimised as

far as reasonably practicable, through the measures

incorporated into the draft Code of Construction Practice (draft CoCP) (e.g. reduce dust emissions through the effective

transportation and storage of materials), including the proposed

monitoring regime.

Not significant

Increased odour

release during

construction due to

higher temperatures

During the construction phase, hotter temperatures may cause

increased odour release through evaporation from the fuel of

construction plant and construction vehicles. This consequence

is minimised, as far as reasonably practicable, through the

measures incorporated into the draft CoCP (e.g. early

identification of materials which could generate odour).

Not significant

Increase in evaporative

emissions from aviation

fuel used by Ground

Support Equipment due

to hotter weather

(Operation)

During the operational phase, hotter temperatures may cause

increased odour release through evaporation from the fuel of

Ground Support Equipment. This consequence is minimised, as

far as reasonably practicable, through monitoring and proposed

environmental measures detailed in Chapter 7: Air quality and odour, such as maintaining the current procedure of a rapid

response to fuel spillages.

Not significant

Changes in

concentration of

pollutants affecting

human health (Nitrogen

Negative impact on human health due to changes in

concentrations of pollutants such as nitrogen dioxide (NO2) and

particulate matter (PM). Although these changes are difficult to

quantify, they are anticipated to be minimal.

Not significant







dioxide and PM) due to

changes in weather

conditions.

Changes in concentrations of pollutants such as nitrogen

dioxide (NO2) and particulate matter (PM) could have an impact

on human health. Although these potential changes are difficult

to quantify, any impacts are anticipated to be minimal.

Regarding aircraft emissions, emissions from combustion of

aviation fuel may be reduced as aircraft require lower thrust to

take off in higher temperatures. In addition, a decrease in the

number of winter stagnation events (where poor air quality is

associated with poor dispersion conditions) would also improve

overall air quality.

Regarding road vehicles, overall air quality is projected to

improve over time as road vehicles are gradually replaced by

newer vehicles which meet tighter emission standards.

Biodiversity (Chapter 8)

Increased

number of hot

days; increase

of droughts

Reduced success of

establishment of new

plantings due to hotter

drier conditions

Resilience of landscaping to climate change will be ensured by

the Habitat Creation requirements provided within the ES to

ensure that climate change is taken into consideration in the

choice of species and adequate monitoring post-planting

occurs. The consequence of the ICCI is therefore deemed to be

minimal.

Not significant

Community (Chapter 11)

Increased

intensity of

extreme

precipitation

events; increase

Impact to access and

levels of use of outdoor

facilities due to flooding

of facilities or of access

roads to them

All facilities will be constructed in line with current design

standards for the relevant type of building (for example, Sport

England Natural Turf for Sport - Design Guidance Note, (Sport

England, 2011)) and the climate change adaptation

requirements of relevant Local Plans, as defined in Appendix

Not significant







in mean winter

rainfall

2.1. Further climate change adaptation requirements within the

building standards will be considered within the development of

the CCAP for ES (Appendix 10.1).

All surface transport infrastructure will be designed to

Environment Agency guidance on Flood risk assessments:

climate change allowances. This is addressed in detail in the

Flood Risk Assessment (Appendix 21.4).

These measures ensure that the consequence of the ICCI on

access and use of outdoor facilities is minimal.

Increased

occurrence of

heatwaves

Potential for indoor

community facilities to

be affected by

overheating

All replacement buildings will be designed in line with the

climate change adaptation requirements of the relevant Local

Plans, as defined in Appendix 2.1. Further climate change

adaptation requirements within the building standards will be

considered within the development of the CCAP for ES

(Appendix 10.1).

These measures ensure that the consequence of the ICCI on

community facilities is minimal.

Not significant

Health (Chapter 12)

Increased

intensity of

extreme

precipitation

events; increase

in mean winter

rainfall

Impact to access of

health facilities

Surface transport infrastructure will be designed to Environment

Agency guidance on Flood risk assessments: climate change

allowances. This is addressed in detail in the Flood Risk

Assessment (Appendix 21.4). Therefore, the consequence of

the ICCI is minimal.

Not significant







Increased

occurrence of

heatwaves

Potential for

replacement buildings

to suffer from

overheating due to

hotter summer

temperatures.

Replacement buildings provided by the DCO Project, will be

designed in line with the climate change adaptation

requirements of the relevant Local Plans, as defined in

Appendix 2.1. Further climate change adaptation requirements

within the building standards will be considered within the

development of the CCAP for ES (Appendix 10.1). Therefore,

the consequence of the ICCI is minimal.

Not significant

Increased

occurrence of

heatwaves

Potential increase in

urban heat island effect

due to increase in built

environment

Design and appropriate landscaping and plantings will mitigate

the potential for an Urban Heat Island effect. Therefore, the

consequence of this ICCI will be minimal. The potential Urban

Heat Island effect has not been modelled as current modelling

techniques are only applicable to larger areas of land than will

be taken by the DCO Project.

Not significant

Increased mean

temperature

(increase in

warm weather)

and increase in

precipitation

Increase in walking and

cycling as modes of

transport, replacing

some of the journeys

currently carried out in

cars, which would

deliver a positive

benefit on health.

Surface access improvements will decrease reliance on private

transport for Heathrow colleagues and passengers. Multi-modal

journeys, especially those including active transport, are

associated with greater levels of physical activity. This provides

an opportunity for a co-benefit: environmental measures can

provide a benefit for human health. This would be a minimal

positive effect.

Not significant

Historic environment (Chapter 13)

Increase in

mean winter

rainfall leading

to increased

groundwater

levels; increased

Changes in

groundwater level could

result in potential

damage to

archaeological or

Potential damage to archaeological or paleoenvironmental

remains in the ground arises when groundwater levels reduce.

Hence, an increase in mean winter rainfall could potentially

have a positive impact, unless it generates a need for additional

flood storage infrastructure, which could damage archaeological

remains.

Not significant







intensity of

extreme

precipitation

events

paleoenvironmental

remains in the ground.

Embedded environmental measures include avoiding changes

to groundwater flows; measures to identify and assess

receptors susceptible to groundwater changes; and measures

to avoid dewatering as far as practicable. With these in place,

the consequence of the ICCI on archaeological and

paleoenvironmental remains is minimal.

Land quality (Chapter 14)

Increased

intensity of

extreme

precipitation

events; increase

in mean winter

rainfall

Potential increased

leaching of

contaminants from soils

due to wetter conditions

and an increase in the

amount of landfill

leachate generated

Where new landfills are created by the DCO Project, these will

be compliant with the Landfill Directive (2001) as transposed by

The Environmental Permitting (England and Wales)

Regulations 2016 (refer to Chapter 14: Land quality, Section 14.10: Assessment of land quality effects). Climate change

impacts on these assets will be considered through further

design and incorporated into the ES, therefore the

consequence of the ICCI is minimal.

Not significant

Increased

intensity of

extreme

precipitation

events; increase

in mean winter

rainfall

Impacts on human

health related to the

contamination of

surface waters or the

shallow groundwater

aquifer, as these have

the potential to impact

workers and

neighbouring residents

The draft CoCP includes environmental measures to mitigate

potential effects upon human health and controlled waters

during construction (for example the use of hardstanding to

prevent accidental spillages to ground, and the covering of

stockpiles to prevent the generation of dusts). These measures

together with the measures to minimise the impacts of severe

weather events in the draft CoCP mitigate the effects of ICCIs

on human health and controlled waters receptors identified

during construction, as far as reasonably practicable.

Not significant

Increased

intensity of

extreme

Damage to newly

installed infrastructure

from aggressive ground

The geo-environmental desk study data (Chapter 14, Section 14.9: Overall Baseline) indicates that the risks associated with

Not significant







precipitation

events; increase

in mean winter

rainfall

conditions (such as

sulphate attack on

concrete) and

geohazards (such as

ground

swelling/shrinkage)

during the construction

and operational phases

could be exacerbated

by climate change. For

example, increased

rainfall and surface

water flooding could

increase the potential

for sulphate attack or

lead to water clogging

and corrosion of

structures.

geohazards under current climate conditions are negligible to

low.

The DCO Project earthworks will be designed in accordance

with the requirements and recommendations of the relevant UK

and European standards for earthworks.

Further climate change adaptation requirements within the

technical standards will be considered within the development

of the CCAP for ES (Appendix 10.1).

Therefore, the effect of ICCIs related to damage to

infrastructure from aggressive ground conditions and

geohazards are considered to be negligible.

Increased

intensity of

extreme

precipitation

events;

increased

seasonality of

rainfall

Change in rainfall

patterns might

exacerbate the damage

to soils, especially

topsoil, whilst it is being

stored for reuse as part

of the DCO Project.

The draft CoCP includes measures for the stripping, handling

and storage of soils and topsoils to prevent damage to their

structure and quality, as far as reasonably practicable. These

embedded environmental measures ensure that the

consequence of this ICCI is minimal.

Not significant







Landscape and visual assessment (Chapter 15)

Increased

occurrence of

heatwaves,

increased

occurrence of

droughts.

Reduced success of

establishment of new

plantings due to hotter

drier conditions

Climate change will be considered in the selection of

landscaping species and the monitoring put in place. Further

information will be provided in the Habitat Creation

requirements within the ES. The consequence of the ICCI is

therefore deemed to be minimal.

Not significant

Noise and vibration (Chapter 17)

Increased

occurrence of

heatwaves

Potential to exacerbate

noise effects on

communities in terms of

individual dwellings and

on a wider community,

due to windows being

open more often due to

an increase in high

temperatures.

The noise assessment criteria assume windows are open when

internal noise levels are considered. Consequently, there is no

further impact on noise effects arising from the ICCI.

Not significant

Increased

summer

temperature;

increased mean

temperature and

humidity

Potential effect on

noise levels caused by

a change in the sound

absorption properties of

the air, arising from an

increase in temperature

and humidity.

The anticipated effect on propagation of construction sound

from changes in temperature and humidity is expected to be

low as construction noise predictions use precautionary

assumptions about the propagation of noise to predict noise

over relatively short distances.

The anticipated effect on propagation of aircraft sound from

changes in average temperature and humidity is expected to be

low, and this will be further explored in the ES.

Not significant

Waste (Chapter 20)

Increased

occurrence of

heatwaves

Potential for an

increase in odour from

The consequence of increased temperatures impact on odour

from landfills is expected to be minimal, as the majority of waste

generated will be inert and not associated with odour. Only

Not significant







off-site and purpose-

built on-site landfill.

construction waste (typically not associated with odour) will go

to local existing and new landfills.

Increased

intensity of

extreme

precipitation

events

Potential mobilisation of

contaminants due to

flooding is addressed

under Land Quality

ICCI assessment

above

Where new landfills are created by the DCO Project, these will

be compliant with the Landfill Directive (2001) (see Section 14.10). As such, it is considered unlikely that the new landfills

could act as a new source of contamination which may result in

contamination of groundwater. The consequence of the ICCI is

therefore expected to be minimal.

Not significant

Water environment (Chapter 21)

Increased

intensity of

extreme

precipitation

events

Increased mean

winter rainfall

Increased

drought intensity

Increased intensity of

extreme weather

events will cause

changes in

groundwater flow and

levels.

Drought periods could

reduce groundwater

flows

Climate change has not been considered within the

groundwater modelling carried out for PEIR (Chapter 21).

Appropriate design and alignment of subsurface features, and

of new and updated drainage networks will be considered in the

CCAP (Appendix 10.1). Climate change will be considered in

the groundwater assessment for the ES. The consequence of

the ICCI on groundwater receptors are expected to be minimal,

but further assessment is required.

Anticipated to be

not significant (subject to further

assessment at ES)

Increased

intensity of

extreme

precipitation

events and

pluvial flooding

Higher intensity and

frequency of rainfall will

increase the number of

flood events that will

occur in the catchment.


frequency of flooding

and more extreme

The Flood Risk Assessment (FRA) in Appendix 21.4 confirms

that the DCO Project design is NPPF compliant (DCLG, 2019),

and therefore considers the impacts of climate change. It

confirms that the proposed design has been developed to avoid

areas of known flood risk wherever possible in line with the

sequential risk-based approach advocated by the NPPF

(DCLG, 2019). Where there are exceptions to this rule the PEIR

FRA presents a range of potential additional environmental

Not significant







Increased mean

winter rainfall

and fluvial

flooding

Increased

drought intensity

precipitation events are

likely to increase the

load of pollutants

washed from soils and

overflows

measures to ensure a safe NPPF compliant development

(DCLG, 2019).

As set out in Section 4.1 of the Drainage Impact Assessment

(DIA) (Appendix 21.5), for flood attenuation purposes, the

climate change allowances provided by the Environment

Agency for flood risk assessments will be used. Appropriate

allowances for increase in peak rainfall intensity will be applied

to cover the lifetime of the DCO Project. As recommended in

the guidance (Environment Agency, 2017), both the central and

upper end allowances will be assessed to understand the range

of impact.

With these environmental measures in place, the consequence

of the ICCI is deemed be minimal.

Increased

intensity of

extreme

precipitation

events and

pluvial flooding

Increased mean

winter rainfall

and fluvial

flooding

Reduced groundwater

recharge and river flow

may result in lower

water quality because

of less dilution of

pollutants. Increased

intensity of floods could

increase erosion of

sediments also

reducing water quality.

Drought events limit

dilution and therefore

increase the

Climate change has not been considered within the water

quality assessments at PEIR stage (Chapter 21 and Appendix 21.1). Water quality assessments will consider climate change

ICCIs at the ES stage. It is expected that the consequence of

the ICCI will be minimal, but further assessment is required.

Anticipated to be

not significant (subject to further

assessment at ES)







Increased

drought intensity

concentration of

pathogens in surface

waters




10.10.10 Climate change has been considered throughout the design process to date. The

CCR assessment considers the embedded environmental measures described in

Section 10.5, as well as the assumptions stated in Section 10.8.

10.10.11 The preliminary CCR assessment outputs are provided in Table 10.21. Only those

climate impacts with a medium or greater consequence, as defined in Table 10.16, have been detailed. Impacts with a consequence of low or very low will be

incorporated in the CCAP where appropriate.

10.10.12 Due to the embedded environmental measures put in place, all likelihoods of

climate impacts are either assessed to be unlikely to very unlikely or are

anticipated to be unlikely or very unlikely following further assessment at ES stage.

Therefore, Table 10.21 focuses on the embedded environmental measures in

place and the resultant risk. A full risk assessment matrix will be provided in the

CCAP.

10.10.13 As asset design develops, climate change will be further considered using relevant

international and national guidance for embedding climate change into technical

standards as listed in Appendix 10.1. This embedded environmental measure is

assumed across all asset groups and is considered in the determination of

significance, but is not referred to in Table 10.21.



Table 10.21: Climate change resilience assessment results

Climate change hazard

Asset groups Climate change impacts

Embedded environmental measures / good practice

Risk Significance

Increased intensity of extreme precipitation events


aprons, including

operations and aircraft

Surface access and

road assets

Increased torrential rain

events create

hazardous conditions

for vehicles and planes

an intolerable amount

of the time (for

example, airside and

landside vehicles).

As set out in Section 4.1 of the

DIA (Appendix 21.5), for flood

attenuation purposes, the climate

change allowances provided by the

Environment Agency for flood risk

assessments will be used.

Appropriate allowances for

increase in peak rainfall intensity

will be applied to cover the lifetime

of the DCO Project. As

recommended in the guidance

(Environment Agency, 2017), both

the central and upper end

allowances will be assessed to

understand the range of impact.

A sensitivity assessment for more

radical changes in climate will be

carried out for the ES.

Monitoring impact of torrential rain

on airside and landside road

vehicles and planes is in place as

good practice.

Low Not significant


aprons, including


Increased rainfall

saturates the unbound

pavement construction,

causing loss of fine

All airfield and road assets will be

designed for the climatic conditions

experienced at the end of their

operational life cycle, using

Low Not significant






Risk Significance

Surface access and

road assets

material and settlement

and subsequent

premature pavement

failure.

Rapid structural

damage from

increasing water

damage. Increases in

precipitation would

increase deterioration

rates for joints and

surfacing, requiring

more frequent

replacement and traffic

disruption.

appropriate design guidance. The

design will be progressed between

PEIR and ES.

New terminal and

associated buildings,

including airside

facilities


control assets

Utilities corridors

Construction sites

Underground assets

inundated and

damaged during pluvial

flooding event (for

example, underground

pipework, pumping

station, tunnels and

utilities corridors).

As set out in Section 4.1 of the

Drainage Impact Assessment (DIA)

(Appendix 21.5), for flood

attenuation purposes, the climate

change allowances provided by the

Environment Agency for flood risk

assessments will be used.

Appropriate allowances for

increase in peak rainfall intensity

will be applied to cover the lifetime

of the DCO Project. As

recommended in the guidance

(Environment Agency, 2017), both

the central and upper end

Low Not significant






Risk Significance

allowances will be assessed to

understand the range of impact.





control assets

Pollution Control

System (PCS)

challenged as a result

of increased severity of

first flush effect and

compounded by less

seasonal distinction in

PCS operation.


frequency of flooding

and more extreme

precipitation events

increase the load of

pollutants washed from

soils and overflows to

unacceptable levels.

An allowance for climate change

has been incorporated into the

water treatment element of the

airfield drainage strategy, as

discussed in Section 4.2 of the

Drainage Impact Assessment

report (Appendix 21.5 of the

PIER). An appropriate factor of

safety has been incorporated into

the designs to safeguard against

adverse changes in climate in the

short term, for instance, sufficient

conservatism has been

incorporated into the design of the

water treatment capacity to provide

an allowance for climate change in

the relatively short term (10 to 15

years). The design calculations for

the water treatment area have

sufficient conservatism built-in to

handle much increased daily

biological oxygen demand (BOD)

loading associated with de-icer

usage in excess of that which

Low Not significant






Risk Significance

occurs under present day climatic

conditions.

For changes in climate beyond the

factor of safety incorporated into

the design (likely to be longer term

changes in climate), the adaptive

management approach detailed in

the Climate Change Adaptation

Plan would be employed. An

adaptive management approach

requires a flexible design, such as

one that allows the depth of the

gravel substrate to be increased,

for example. The feasibility and

practicality of undertaking such an

approach will be considered when

designing the co-located water

treatment and attenuation areas.

Increase in mean winter rainfall


aprons, including


New terminal and


including airside

facilities

Surface access and

road assets

Increased fluvial flood

risk across the DCO

Project

The Flood Risk Assessment

(Appendix 21.4): confirms that The

DCO Project design is NPPF

compliant (DCLG, 2019), and

therefore considers the impacts of

climate change. It confirms that the

proposed design has been

developed to avoid areas of known

flood risk wherever possible in line

with the sequential risk-based

approach advocated by NPPF

(DCLG, 2019). Where there are

Low Not significant






Risk Significance


control assets

Fuel assets

Utility corridors

Flood alleviation and

storage infrastructure,

fire water and energy

storage assets.

exceptions to this rule the PEIR

FRA presents a range of potential

additional environmental measures

to ensure safe NPPF compliant

development (DCLG, 2019).




Increased seasonality of rainfall Increase in mean winter rainfall

Earthworks, with

knock-on effects on:


aprons, including


New terminal and


including airside

facilities


control assets

Surface access and

road assets



Variable groundwater

levels affect asset

integrity and cause

subsidence and water

ingress damage to

earthworks,

underground

structures, foundations

and platforms

The DCO Project earthworks will

be designed in accordance with the

requirements and

recommendations of the relevant

UK and European standards for

earthworks

These documents include a

requirement for climatic change to

be considered during the design of

earthworks, buried structures and

foundations and the impact on

earthworks or structural

performance (stability and ground

movement) to be assessed.

Current threshold levels that impact

performance will be assessed

against projected climate changes

over the proposed design life of

Low Not significant






Risk Significance


storage assets

On and off-site

electrical facilities and

utilities corridors

earthworks and structures to

ensure appropriate resilience to

climate change. This will focus on

the influence of changes in

precipitation on groundwater levels

and soil moisture content and the

resultant potential impact on

ground movements and earthworks

stability.

The design of earthworks,

underground structure and

foundations will be undertaken

applying conservative groundwater

level assumptions. These will be

assessed from consideration of

existing groundwater monitoring

data and the results of

hydrogeological modelling that

itself will include the assessment of

projected climatic variations at the

ES stage.

Permanent site drainage proposals

include allowance for projected

climate change. This will help to

mitigate the risk to earthworks and

underground structures from

drainage capacity being exceeded

during operation.






Risk Significance

Earthworks, with

knock-on effects on:


aprons, including


Surface access assets

Expansion and

shrinking of soil causes

pavement layers to

heave. Changes to

groundwater levels

affect asset integrity,

causing subsidence

and water ingress

damage to surfaces.

Underground

infrastructure suffers

fracture risk.

The DCO Project earthworks will

be designed in accordance with the

requirements and


UK and European standards for

earthworks.

These documents include a

requirement for climatic change to

be considered during the design of

earthworks, buried structures and

foundations and the impact on

earthworks or structural

performance (stability and ground

movement) to be assessed.

Current threshold levels that impact

performance will be assessed

against projected climate changes

over the proposed design life of

earthworks and structures to

ensure appropriate resilience to

climate change. This will focus on

the influence of changes in

precipitation on groundwater levels

and soil moisture content and the

resultant potential impact on

ground movements and earthworks

stability.

Low Not significant






Risk Significance

The design of earthworks,

underground structure and

foundations will be undertaken

applying conservative groundwater

level assumptions. These will be

assessed from consideration of

existing groundwater monitoring

data and the results of

hydrogeological modelling that

itself will include the assessment of

projected climatic variations at the

ES stage.

Permanent site drainage proposals

include allowance for predicted

climate change. This will help to

mitigate the risk to earthworks and

underground structures from

drainage capacity being exceeded

during operation.

Increase in mean winter rainfall leading to increased groundwater levels


aprons, including


New terminal and


including airside

facilities

Fuel assets

Inundation of assets

though groundwater

flooding.

Groundwater modelling does not

incorporate climate change at

PEIR. It will be included in the ES.

Potential impacts will continue to

be considered as detailed design

progresses.

Low Anticipated to be not significant (subject to

further assessment at

ES)






Risk Significance


control assets

Increased summer temperature; Increased number of hot days and heatwaves


aprons, including


Heat damage to tarmac

and pavements in

airfield, including

apron, runway and

airside roads through

surface failure, warping

of slabs and excessive

movement at joints.

All airfield assets will be designed

for the climatic conditions





PEIR and ES.

Surface condition on extreme

temperature days are monitored by

airside and landside operations

teams to ensure safe operations.

Low Not significant


Heat damage to road

surfaces and assets

through surface failure,

warping of slabs and

excessive movement at

joints.

All road sub-assets will be


experienced at the end of their life

cycle (e.g. relaying of road surface,

or replacement of sub-base will

have substantially different

lifespans), using appropriate

design guidance. The design will

be progressed between PEIR and

ES.

Low Not significant

New terminal and


including airside

facilities

Buckling of metal

structures in buildings,

pipework.

The DCO Project will be designed

in accordance with the

requirements and


UK standard for actions on

Low Not significant






Risk Significance


control structures

Utilities corridors

structures. This includes

requirements for ambient design

temperatures. The adequacy of

these standards will be assessed

throughout the detailed design

stage, and the projected conditions

will be applied to the design.

All buildings will be designed for

the climatic conditions experienced

at the end of their operational life

cycle, using appropriate design

guidance. The design will be

progressed between PEIR and ES.

Utilities corridors Extreme heat damages

power infrastructure

cabinets and sub-

stations, amplified by

solar gain.

All utilities assets will be designed

for the climatic conditions





PEIR and ES.

Low Not significant

Project-wide Fire risk on site

increased to

unacceptable level.

Recent assessments and

developments of existing fire main

means current operations sufficient

to mitigate risk. Good practice will

be extended to the new assets.

Low Not significant

Increased number of hot days and heatwaves

Fuel assets Flashpoint of aviation

fuel exceeded on hot

days.

Airport fire service embedded in

Operational Resilience Plan

(Heathrow Airport Limited, 2015).

Good practice of working with fuels

Low Not significant






Risk Significance

and research into spill clean-up

operations in hotter climates

means perceived risk of fuel

combustion is low.

Construction sites

Project-wide

Heat risk to staff

causing a danger to

life.

Wellbeing toolkit provides sun

awareness briefings to manage

heat impacts. Team briefings take

place on hydration.

The draft CoCP includes

requirements for a high-level risk

assessment of severe weather

impacts on the construction

process to be produced by the

main contractor to inform

mitigations. Any receptors and/or

construction-related operations and

activities potentially sensitive to

severe weather events should be

considered in the assessment.

Climate change projections are

considered in the risk

assessments.

The main contractors’

Environmental Management

System should consider all

measures deemed necessary and

appropriate to manage severe

weather events and should as a

minimum cover training of

Low Not significant






Risk Significance

personnel and prevention and

monitoring arrangements. As

appropriate, construction method

statements should also consider

severe weather events where risks

have been identified.

The DCO Project will be designed

in accordance with the

requirements and


UK standard for action on

structures. This includes

requirements for ambient design

temperatures. The adequacy of

these standards will be assessed

throughout the detailed design

stage, and the projected conditions

will be applied to the design.

Increased mean temperature


aprons, including


Substantial increase in

frequency of bird

strikes.

Monitoring of movement of birds

across Heathrow Airport has been

ongoing since 2011, with the

results fed into the Heathrow Bird

Strike Group. Biodiversity Action

plans monitor species on sites.

This good practice will follow the

requirements of the CCAP to

ensure environmental measures

are put in place if and when

required.

Low Not significant






Risk Significance

Increased winter temperature variability and freeze/thaw

Construction sites


control assets

Utilities corridors


Fracture risk to

underground

infrastructure.

New services are not laid at

shallow depths to avoid damage

due to temperature extremes

during excavations.

All road sub-assets will be


experienced at the end of their life

cycle (e.g. relaying of road surface,

or replacement of sub-base will

have substantially different

lifespans), using appropriate

design guidance. The design will

be progressed between PEIR and

ES.

Low Not significant

Increased variability of snowfall and extreme snowfall events


aprons, including


Increased variability of

snowfall challenges

winter contingency

plans, de-icing supplies

and Heathrow

colleagues experience.

New de-icing facilities are

incorporated into the DCO Project.

Continued implementation of the

actions from the Heathrow Winter

Resilience Enquiry (2011),

including continual development of

the snow removal plan.

Low Not significant

Possible increased frequency and intensity of lightning events


aprons, including


Airfield telecoms

Fuel assets

Unacceptable increase

in Impact on control

systems and electricity

supply from lightning

strike. Power cuts and

voltage spikes to parts

of Heathrow Airport not

Monitoring of weather trends in

place, and updates to processes

and planning through incorporation

of adaptive management as

detailed in the CCAP.

Low Not significant






Risk Significance

run on UPS during

electrical storms.

Lightning protection units installed

where risks to sub-components is

high. Redundancy in power intake

due to three separate intakes from

National Grid is already existing

and another is included in the DCO

Project.

Possible increased frequency and intensity of wind events


aprons, including


New terminal and


including airside

facilities

Airfield telecoms

Substantial damage to

building fabric caused

by high winds.

Failure of lighter

structures by

overturning.


masts during periods of

extreme winds.


de-icing equipment

during periods of

extreme winds.

Monitoring of weather trends in

place, and updates to processes

and planning through incorporation

of adaptive management as

detailed in the CCAP.

All buildings will be designed for

the climatic conditions experienced

at the end of their operational life

cycle, using appropriate design

guidance. The design will be

progressed between PEIR and ES.

Low Not significant

Drought New terminal and


including airside

facilities



Reduced availability of

potable water for

operations and terminal

buildings.

Water efficiencies are built into the

DCO Project through the draft Resource Management Plan

(Appendix 20.1). This enables an

increase in the level of efficiency in

water use per passenger, therefore

increases resilience to drought

Low Not significant






Risk Significance


storage assets

events. The measures

incorporated are:

1. Utilising new approaches

and technology to

eliminate water demand

and improve water

efficiency for all uses, both

potable and non-potable

2. Proactively influence

business partners’

development and

operations and growth to

improve water efficiency

3. Undertaking measures to

minimise leakage levels in

the new facilities and

reduce leakage in existing

facilities that are

undergoing expansion or

supporting expansion

facilities and

4. Increase the use of non-

potable water supply to

meet the demand from all

the non-potable end uses

(such as WC and urinal

flushing, cooling towers,

etc.).



Risks from interdependencies

10.10.14 As well as the risks within the Site, the DCO Project is subject to several ‘cascade’

risks from its interdependencies such as electricity, gas, transport and

telecommunications networks, as well as effects on destination airports and their

networks. These risks have not been included in Table 10.21 as many of the

environmental measures required for reducing the likelihood of their occurrence

are not under the control of Heathrow.

10.10.15 The relevant UK infrastructure operators (for example, Highways England,

National Grid, UK Power Networks, water companies etc.) supply Climate Change

Adaptation Reports (Defra, 2017b) under the Climate Change Act 2008 and are

subject to climate change adaptation requirements in the planning system.

Furthermore, Heathrow’s resilience framework is designed to cope with temporary

disruptions to supply of utilities. The draft Resource Management Plan

(Appendix 20.1) sets out how Heathrow will be more resilient to power, heating

and water resource shocks.

10.10.16 Risks from interdependencies will be considered in greater detail in the CCAP.

Concluding statements

10.10.17 There are no medium or high risks relating to climate change resilience, and

therefore no significant effects. This is due to the embedded environmental

measures described in Table 10.8, while taking into account the assumptions

detailed in Section 10.8 and the requirement for consideration of climate change

in design standards across all asset groups in the CCAP (Appendix 10.1).

10.10.18 The principles of the CCAP are presented in Appendix 10.1. The full CCAP will be

appended to the ES.

10.10.19 The effects of more radical changes in climate will be considered in greater detail

in the ES, where sensitivity testing will be carried out where appropriate. There will

also be assessment of supply chain risks within the CCAP.

Preliminary assessment of significance

10.11.1 There are no significant effects remaining following the assessment of climate

change impacts on the construction and operational phases of the DCO Project

and its receptors. This is because all relevant and implementable environmental

measures have been embedded into the DCO Project or will be addressed by

further assessment in the ES (refer to Table 10.8).



Assessment of cumulative effects

10.12.1 The CCR assessment is only concerned with the assets of the DCO Project and a

broader consideration of existing interdependent infrastructure, therefore a

cumulative effects assessment (CEA), is not required.

10.12.2 The ICCI assessment is an assessment of the exacerbation of climate change on

existing effects. As the climate change projections have been included within each

aspect’s primary assessments, and are therefore carried through to the aspect-

specific CEA, a separate Climate Change CEA is not required.

Consideration of additional environmental measures and compensation

10.13.1 No additional environmental measures are proposed to further reduce the climate

change effects that are identified in this PEIR. This is because all relevant and

implementable environmental measures have been embedded into the DCO

Project design and are assessed in this chapter. These environmental measures

are considered likely to be effective and deliverable, and would address the likely

significant effects of the DCO Project.

10.1.1 As no additional environmental measures were required, the final stages of the

ICCI and CCR assessments methodologies described in Graphic 10.2 and

Graphic 10.3 were not carried out.

Next Steps

Introduction

10.14.1 Further work that will be undertaken to support the climate change assessment

and presented within the ES is set out below.

Baseline

10.14.2 Operational performance statistics will be mapped against weather and climate

information to increase understanding of how existing assets and systems respond

to stresses, therefore enriching the evidence base.

Assessment

10.14.3 Supplementary survey data (for example, biodiversity) and modelling (for example,

Flood Risk) mean that the ICCI and CCR assessments will be refined from the

PEIR to ES to incorporate new information and detail.



10.14.4 The climate hazards assessment will be updated to include elements of UKCP18

due in 2019, most notably the 2.2km projections that provide information on

localised extreme precipitation events. These will be used in more detailed

assessment of pluvial flooding. A more thorough assessment of UKCP18

information that combines the different tools available will be carried out where

appropriate, and the level of design warrants it.

10.14.5 The CCR assessment will incorporate more radical changes in climate using

sensitivity analyses where appropriate. The process for considering them in the

design and operation of the DCO Project will be described in the CCAP.

10.14.6 The full CCAP will be appended to the climate change aspect ES chapter. The

CCAP will outline the process by which the DCO Project will maintain resilience to

climate change throughout its design and construction, as well as through its

operation within the context of the existing airport.

Engagement

10.14.7 Further engagement that will be undertaken to inform the assessment of climate

change and presented within the ES is set out in Table 10.22.

Table 10.22: Further engagement

Engagement Participant Issues to be addressed Relevance to assessment

HSPG Communication of the CCAP

approach and seek agreement

on Community ICCI assessment

approach.

Required for consideration of

climate change in the ES.

Natural England Seek agreement on biodiversity

and landscape ICCI assessment

approach, as well as input to

climate change elements of the

green infrastructure and

landscape design strategy

documents.



Public Health England Seek agreement on Health ICCI

assessment approach.



Environment Agency Seek agreement of approach to

considering climate change in

groundwater modelling, and the

assessment of water quality.



Documents

Volume 1, Chapter 10 Climate change...2019/06/12 · Climate change 10.1 Introduction 10.1 Relevant legislation, policy and other important and relevant matters 10.3 Introduction