Heathrow: a solution to runway blunders
The NPS stipulates a runway length of at least 3,500 metres which is very costly to construct, not least because it has to get across a wide M25 at a point where the motorway probably is Britain’s busiest. The proposal is to place the motorway in a tunnel. The Airports Commission thought its cost would be about £0.58bn. Highways England considers that there is significant potential for cost overruns and places an upper estimate in excess of £1.0bn (at 2014 prices).
The runway will also plough through the Lakeside energy from waste plant, the relocation of which according to the Airports Commission “…would be a substantial exercise in its own right…” (Final Report: 11.35). But the waste plant removal and the motorway works result in the last few hundred metres of runway being a very costly and, to motorists, disruptive undertaking.
Curiously, all previous suggestions for a new runway at Heathrow have been for shorter lengths, avoiding the motorway problem. Back in 2007, the government consulted on a 2000m runway; by 2009 this had been pushed out to 2,200 and then, during the early deliberations of the Airports Commission, HAL came up with a plan for a 2,800m scheme. The current proposed length stems from later options submitted to the Airports Commission for what was referred to as a full-length runway. The additional length raises prospective capacity to 740,000 annual movements, a mere 5.5 per cent increase compared with the former shorter runway proposal.
The latest twist to this story is that in January 2018 HAL suggested it might cut 300m from the runway length to save costs, but the need to bury or move the M25 remains. Presumably, this chop to the length cuts potential runway capacity (if not why the extra concrete in the first place)? It means of course that those remaining few hundred metres, requiring drastic surgery to the M25, come at a mind-boggling marginal cost.
The obvious ‘compromise’ is to forgo a trivial amount of runway capacity and pull back the length so that it does not cross the M25. Not only will this save a lot but it will undoubtedly bring forward the opening date for the badly needed additional runway. However, due to HALs vaulting ambition and the Department’s short-sightedness in incorporating a minimum length in the NPS, there is a snag. Opponents of expansion have threatened Judicial Review for any length shorter than 3,500m on the grounds that the economic case rested on this length of runway.
So let me offer another ‘compromise’ based I believe on a commonsense proposal that I first made in 2015. Build the full length runway, but build it in two phases. The initial phase could be constructed up to the M25, a length of approximately 2,500m. At the western end of this initial runway, a safety zone of several hundred metres is created for the workforce to continue constructing the extension over the M25. This would still allow, using the remainder of the first phase of construction, a runway of over 2000m for short-haul flights (leaving more space on existing runways for more long-haul flights). This is about the same operational length as the existing runway at London Luton. Extending a runway whilst in daily use is not exceptional; Birmingham International recently extended its main runway by 400m.
The phasing of the works would have a number of major benefits. First, it would allow more time for planning and executing the difficult task of bridging or tunnelling the M25, (a task which on the present timetable Highways England consider “extremely challenging”) thereby reducing risks of disruption to a critical part of the UK strategic road network.
Second, the simplification of the immediate construction task would allow substantial additional runway capacity to become available more quickly than building a one-off full-length runway, bringing forward benefits for the UK economy.
Third, significant construction costs could be deferred for a few years and this, together with an earlier cash-flow from the use of Phase One, would help the airport to achieve its aim of broadly maintaining current charges to airlines.
What, apart from building a much shorter runway, could be more straight-forward?