You’ve probably already seen it in our weekly look back at air traffic. The Zwanenburgbaan Runway was deployed for a few hours due to works on the Polderbaan. Or, the Buitenveldertbaan Runway was used because of brief maintenance on the Kaagbaan Runway. But what do these works entail?
The runways at Schiphol are subject to intensive use. Especially the Kaagbaan and Polderbaan, which are almost always available as they are preferential runways. Regular maintenance is required to keep the runways in good condition. Every year, each runway undergoes maintenance for around one week or a week and a half and is therefore unavailable for air traffic. We refer to that as standard maintenance, and there’s an annual plan for that. One runway per year undergoes major maintenance, which means that it isn’t available for between 6 to 7 weeks or between 10 to 16 weeks. Major maintenance often has longer-term consequences for runway use. As a result, our neighbours experience sometimes more or sometimes less noise nuisance.
In addition to standard and major maintenance, we carry out brief maintenance activities every eight weeks. These include checking and repairing the asphalt, replacing runway lighting, removing rubber left behind by aircraft tyres, fixing minor damage, mowing the grass and removing weeds. We do this kind of short-term maintenance six to seven times per year on each runway. And there are other works that need to be done to keep the runways in use, such as construction projects for a new taxiway, rainwater drainage and work on technical systems in the machine room.
Runways are not available when they are undergoing short-term maintenance and works. This can result in anomalous runway use and therefore noise nuisance. That’s why these works preferably take place when there are no aircraft due to take off from or land on the runway. For the Aalsmeerbaan, Buitenveldertbaan, Schiphol-Oostbaan and Zwanenburgbaan runways, that often means outside of peak times or at night. Planning this is quite a puzzle, especially when it comes to the preferential runways – the Kaagbaan and Polderbaan – that are almost always in use. We then have to choose a moment when fewer aircraft are scheduled on these runways, so that we only have to move a few flights to other runways. Moreover, the nature and duration of the works determine whether they can take place during the day or at night.
As you can imagine, we cannot wait long before carrying out emergency works. It is therefore possible that a runway is not available for several hours. Before we start works on a runway, we first look at whether weather conditions and air traffic volumes allow us to deploy another runway. If postponing works would be better for local residents - and if the nature of the work permits - we postpone the works. Deploying a different runway may sometimes lead to noise nuisance in the area. That’s why we try to complete the works as quickly and efficiently as possible.
You can find two noise-reducing measures that apply to short-term maintenance on the preferential runways on minderhinderschiphol.nl (in Dutch only). One is a measure to limit take-offs from the Kaagbaan Runway towards the north-east at night when there are maintenance works going on (Beperken nachtelijke starts Kaagbaan in noordoostelijke richting bij baanonderhoud). The other is a measure to limit take-offs towards the south from the Zwanenburgbaan Runway when there are short-term maintenance works going on (Beperken nachtelijke starts Zwanenburgbaan in zuidelijke richting bij kort baanonderhoud). There is also a measure aimed at improving the planning and strategy of runway maintenance and works, with which we try to limit the overall impact of maintenance as much as possible (Verbeteren planning en strategie baanonderhoud en werkzaamheden).