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Figure 6.4: Heathrow northwest runway terminal potential options Heathrow Airport Expansion Consultation Document (page 19)

Taxiways

6.52 New taxiways will be required to connect the new runway with aprons and terminals. As the latter are not fixed the locations of taxiways also have yet to be finalised. HAL is considering three broad areas for new taxiways to link the new expansion facilities to the existing taxiway system (figure 6.5). It is possible that new taxiways will be needed in each of the following areas to deliver the expansion proposals:

• Area 1 – West of T5

• Area 2 – West of what will become the central runway

• Area 3 – North and south of what will become the central runway

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Figure 6.5: Heathrow northwest runway taxiway potential options Heathrow Airport Expansion Consultation Document (page 21)

Roads

6.53 The AECD confirms that the airport expansion will require changes to be made to the existing road network, and existing traffic flows. A commitment has been made by HAL not to increase the amount of airport related traffic on the road and to ensure that its neighbours benefit from the improvements to local and regional connections. Heathrow Airport is undertaking further work to understand future traffic demand and distribution and inform the provision of future road capacity and local connections. The following roads will be directly affected by the proposed expansion works:

• M25

• A4

• A3044

• Local access roads and junctions

6.54 The new north west runway will extend westwards and cross the existing M25, between junctions 14 and 14a and affect their operation. Having considered options the airport proposes to re-position the M25 carriageway approximately 150 metres to the west, lower it by approximately 7 metres into a tunnel and raise the runway height by 3 to 5 m so that it passes over the M25 between J14a and

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J15. An option for the M25 to incorporate collector-distributor roads is being considered.

6.55 Whilst J15 is not expected to be affected (other than minor works), the AECD states that the closure of some local roads is likely to result in more traffic wanting to pass through J14 and J14(a) and it is likely that Heathrow will need to improve their capacity. Two families of options are considered to exist to achieve this. Family 1 would require the redevelopment of J14 and the alteration of Junction 14a, and Family 2 would require the redevelopment of J14 and closure of Junction 14a.

Local roads

6.56 The expansion will result in the loss of a section of the A4 between Colnbrook and Sipson, potentially impacting upon accessibility to the airport for local communities situated to the north. The AECD presented three diversion options (options 2E, 3A and 6C). Options 2E and 3A re-align the A4 to the north of the new runway, with 6C routing to the south. These are shown in figure 6.6.

Figure 6.6: Heathrow northwest runway scheme A4 potential options Heathrow Airport Expansion Consultation Document (page 27)

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6.57 The new runway will also result in the removal of a section of the A3044, affecting local access to the western side of the airport, especially from the Poyle and Colnbrook area. The AECD identifies the following four options (2a, 2ai, 3d and 3g) for re-establishing this route as shown in figure 6.7:

• Option 2a provides a north-south route running under the new runway connecting to the re-aligned A4

• Option 2ai – similar to Option 2a, but connects to a realigned A4 south of the new runway

• Option 3d – a short, direct route east of Poyle and north of Colnbrook avoiding the village centres.

• Option 3g – a route south of Poyle and Colnbrook, and through a gap between Colnbrook and Brands Hill

Figure 6.7: Heathrow northwest runway scheme A3044 potential options Heathrow Airport Expansion Consultation Document (page 28)

6.58 The proposals will also require upgrades to key junctions including the Stanwell Moor junction and may include the construction of a new southern access to the Central Terminal Area.

River Diversions and Flood Storage

6.59 Given that the Heathrow expansion will extend the airport into the Colne Valley, there will be a need to alter some watercourses and areas of floodplain. The works are likely to affect the River Colne, the Colne Brook and the Wraysbury River. Several options (C1A, C1C, C1D and C1E) are presented in the AECD

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document, that would divert watercourses under the runway, or diverting the Colne Brook around the western edge of the runway, or a wider diversion around Colnbrook in open channels.

6.60 Options being considered for replacement flood storage include on-airport storage and/or new up-stream storage.

Airport supporting facilities

6.61 The AECD states that land will be required to accommodate:

• Airport supporting facilities

• Land uses affected by expansion

• Airport related development

• Areas of landscaping and biodiversity mitigation

6.62 These uses include on-airport cargo capacity, aircraft maintenance and repair facilities, other supporting facilities and car parking. They also include replacement of immigration removal centres together with the Lakeside facilities, Waterside offices, BT data centre and maintenance deport, Total fuel depot, overhead power lines and substation and other existing commercial uses. Airport related development is expected to include hotels, offices, industrial and warehousing.

Construction

6.63 In order to facilitate airport expansion there will be a need for land in and around the airport for construction purposes. This includes construction worker offices, industrial plants and maintenance sites, control posts and site entrances, a new railhead, lorry parks, areas to produce, combine and store materials and workforce car parking. The AECD identifies areas of land around the airport, including the replacement EfW and HTI facilities site as potential temporary construction sites.

6.64 HAL recognises that there is a need to minimise the impact of construction on local communities, stakeholders and airport users and cites this as a key priority. Measures identified to reduce the effects of a large number of activities taking place at the same time include the use of advanced planning and logistics, such as to:

• Use rail freight to import bulk materials, reducing vehicle movements and effects on local roads

• Use pre-booked delivery slots to allow the time of each delivery to be controlled

• Provide bus services to transport the construction workforce to and from parking zones, areas of accommodation and linking to the public transport network

• Use logistic hubs to pre-assemble and consolidate components before transporting them to Heathrow. This approach can deliver better quality products than building everything on-site and help make the project affordable and more environmentally sustainable.

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6.65 HAL proposes the use of sustainable construction approaches. This could include the adoption of just in time deliveries to reduce the use and wastage of materials, the use of ultra-low or zero emission vehicles and construction techniques and maximising the use of recycled materials while minimising water and energy consumption on site.

6.66 In addition, HAL proposes to develop and consult on a code of construction practice that sets out proposed measures and standards of work that will be applied throughout the construction period. This will include information on the measures proposed to minimise effects on local communities, manage construction worker accommodation and the proposed construction working hours. Best practice management will be applied to manage construction works and drive continuous improvements.

6.67 The consultation provides a summary map (see figure 6.8 below) identifying all of the key features of the emerging proposals in respect to the west of the airport covering the Poyle, Colnbrook and Brands Hill area and the proposed site of the replacement EfW and HTI facilities.

Figure 6.8: Key features on the West (Poyle, Colnbrook and Brands Hill) Heathrow Airport Expansion Consultation Document (page 47)

Surface access

6.68 Heathrow Airport is preparing a surface access strategy that will ensure that by 2030 at least 50% of surface access passengers arriving or departing Heathrow will be by public transport, rising to 55% by 2040. It identifies eight initiatives to drive this strategy:

• Putting Heathrow at the heart of the rail network