ryanpanos: How Amsterdam’s Airport Is Fighting Noise…

How Amsterdam’s Airport Is Fighting Noise Pollution With Land Art | Via
Amsterdam’s Schiphol Airport, located just 9 km southwest of the city, is the third busiest airport in Europe and one of the busiest in the world. In an average year, more than 63 million passengers pass through Schiphol in as many as 479,000 flights to and from various international destinations. That’s an average of about 1,300 flights every day, or nearly a flight every minute. In other words, Schiphol is very busy and very loud. When the Dutch military first built a landing strip here in 1916, they chose the site because it was a polder —a broad and flat lowland that used to be the bed of a vast lake. Over the decades the flat expanse of the Haarlemmermeer polder became one of the most densely populated areas of the country, and the noise produced by the airport became an annoying problem for the residents. For years, residents complained about the incessant rumbling din produced every time an aircraft took off. This type of noise, called ground-level noise, propagates across the flat and featureless Haarlemmermeer landscape that has nothing in between—no hills, no valleys— to disrupt the path of the sound waves. When the airport opened its longest runway in 2003, residents could hear the din more than 28 km away. To tackle the noise problem, the airport brought in an unlikely candidate—an architecture firm called H+N+S Landscape Architects and artist Paul De Kort. The idea to engage a landscape artist to solve a technical problem was born out of an accident. In 2008, after a failed attempt to control noise, the Schiphol Airport officials discovered that after the arable land between the runway and the surrounding settlements were ploughed, the noise dropped. So Paul De Kort dug a series of hedges and ditches on the southwest of the airport, just past the edge of the runway. The distance between the ridges are roughly equivalent to the wavelength of the airport noise, which is about 36 feet. There are 150 perfectly straight and symmetrical furrows with six foot high ridges between them. These simple ridges have reduced noise levels by more than half.