Heathrow Airport Ltd is recommending construction of a third runway, either to the north, northwest or southwest of the existing airport. All three options have been submitted to the Airports Commission, which is conducting a review for the government.

Projected costs range between £14bn and £18bn and would increase passenger capacity from today’s 80 million to 123 million or 130 million, depending on length and location of the runway.

Each option would raise the capacity at Heathrow to 740,000 flights a year from the current limit of 480,000.

The north option would be the cheapest and easiest to build but would deliver the least benefit. It also has the biggest residential property impact. Heathrow believes the two westerly options offer the greater advantages. They deliver a full-length 3.5km third runway, rather than the 2.8km of the northerly option, while minimising the impact on the local community from noise and compulsory house purchases.

The northwest option performs better on noise and residential property impact than the north option whilst costing slightly more and taking slightly longer to build. The southwest option further improves the situation for some local residents but increases the cost, timescale and construction complexity.

Under the southwest option, the runway would be built over the King George VI and Wraysbury reservoirs, with a new apron and terminal facilities built over Stanwell Moor. A total of 850 homes would be demolished. A section of the M25 would also be put in a tunnel.

Heathrow chief executive Colin Matthews said: “After half a century of vigorous debate but little action, it is clear the UK desperately needs a single hub airport with the capacity to provide the links to emerging economies which can boost UK jobs, GDP and trade. It is clear that the best solution for taxpayers, passengers and business is to build on the strength we already have at Heathrow. Today we are showing how that vision can be achieved whilst keeping the impact on local residents to an absolute minimum.”

Details of Heathrow’s options

Northwest option

Objective

• To place the new runway as far west as possible to reduce the impact of air noise over central London and to reduce the number of residential properties lost, whilst avoiding moving reservoirs and impacting on their associated Special Protection Area.

Location

• Sipson and Harlington are retained to the east as are Colnbrook and Poyle to the west but this option runs through the River Colne valley also affecting a number of other adjacent watercourses. The expanded airport boundary requires the purchase and demolition of residential properties in Harmondsworth and Longford. The listed buildings of the Tithe Barn and St Mary’s Church, Harmondsworth are also directly impacted and would require careful mitigation solutions, although an optimised version of this option may allow these to be retained.

Airfield

• Third runway length – 3,500m
• Separation from existing northern runway – 1,330m in order to align with the M4 corridor which contains fewer residential properties, thus reducing the noise impact
• Taxiways – linked to the existing airport using ‘around the end taxiways’ to the west of the existing northern runway, which permit the existing runway to operate independently and at full capacity.

Terminals and aprons

• Terminal 5 (c30-35 million passengers per annum) – continues to serve the existing Terminal 5 apron and piers (T5B and T5C)
• Terminal 6 (c20-25mppa) – a new terminal building to the west of Terminal 5 to serve the new North West apron
• Terminal 2 (c55-60mppa) – terminal building is extended to the north of the Phase 1 building currently under construction, serving both the eastern apron within the current airport boundary and a redeveloped rectilinear apron on the old Terminal 3 site
• Terminal 4 (c10mppa) – continues to operate as it does today.

Land use and roads

• The M4/M25 motorway junction requires major reconfiguration to accommodate the third runway
• Car parking has been re-developed to the north of the A4 Bath Road and to the south west of the airport
• Additional ancillary development has been zoned between the new runway and existing northern runway, as well as to the south west of the existing airport.

Southwest option

Objective

• To place the new runway as far west as possible to reduce the impact of air noise over central London and to minimise the residential property loss required by the airport boundary.

Location

• To the west of Staines Reservoir and between Wraysbury to the north and the Thames river at Runnymede to the south. Although the expanded airport boundary requires the purchase and demolition of residential properties in Stanwell Moor, the overall residential impact of the option is relatively lower than other options. Impacts on the reservoir and the SPA would require compensatory replacement.

Airfield

• Third runway length – 3,500m
• Separation from existing southern runway – 1,650m, in order to reduce the impact upon Wraysbury Reservoir and to avoid the Wraysbury community, whilst avoiding the Thames river, Runnymede memorial site and high ground to the south
• Taxiways – linked to the existing airport using ‘around the end taxiways’ to the west of the existing southern runway, which permit the existing runway to operate independently and at full capacity.

Terminals and aprons

• Terminal 5 (c30-35mppa) – continues to serve the existing Terminal 5 apron and piers (T5B and T5C)
• Terminal 6 (c20-25mppa) – a new terminal building to the west of Terminal 5 to serve the new North West apron
• Terminal 2 (c55-60mppa) – terminal building is extended to the north of the Phase 1 building currently under construction, serving both the eastern apron within the current airport boundary and a redeveloped rectilinear apron on the old Terminal 3 site
• Terminal 4 (c10mppa) – continues to operate as it does today.

Land use and roads

• M25 motorway relocated in tunnel between Junctions 13 and 14 to pass underneath the third runway
• Wraysbury and King George VI reservoirs require modifying or rebuilding. Staines Reservoir is retained but detailed analysis is required of the reservoir embankment height and the overall reservoir re-provision strategy
• Car parking has been consolidated along the A4 Bath Road corridor
• Additional ancillary development has been zoned to the west of Terminal 5 and to the south west of the existing airport

North option

Objective

• To place the new runway where no disruption to the motorway network or reservoir infrastructure is required, whilst also attempting to minimise the impact on important heritage sites.

Location

• Harmondsworth can be retained to the west, avoids the River Crane to the east and enables listed buildings such as St Mary’s Church, Harlington and St Dunstan’s Church, Cranford to remain. The expanded airport boundary requires the purchase and demolition of residential properties in Sipson and Harlington.

Airfield

• Runway length – 2,800m, because of the impact a 3,500m runway would have on Harmondsworth
• Separation from existing northern runway – 1330m, to align it with the M4 corridor which contains fewer residential properties, thereby reducing the noise impact. This could potentially be reduced further in future optimisation which would reduce the impacts on both Harlington and Cranford Park.
• Taxiways – linked to the existing airport using ‘around the end taxiways’ to the east of the existing northern runway, which permits the existing runway to operate independently and at full capacity.

Terminals and aprons

• Terminal 5 (c50-55mppa) – extended to the south and serving an expanded western apron built over the redeveloped Terminal 3 site
• Terminal 2 (c60-65mppa) – extended to the north of the Phase 1 building under construction, serving both the eastern apron within the current airport boundary and a new apron to the north
• Terminal 4 (c10mppa) – continues to operate as it does today.

Land use and roads

• M4 spur to be realigned into a tunnel underneath the new third runway
• Car parking has been consolidated along the A4 Bath Road corridor
• Additional ancillary development has been zoned between the new runway and existing northern runway as well as to the south west of the existing airport.

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