Park's hilly grooves bounce jet noise skyward

Getting Around: Netherlands could serve as model in easing O'Hare problem

Could the serious jet noise problem over the Chicago area be mitigated by redesigning some forest preserves and parks to replicate plowed farm fields, maybe with public art and other amenities blended in too?

Seemingly stranger ideas have proved successful to address problems at O'Hare International Airport, such as using goats, donkeys and other grazing animals on the airfield to reduce nesting spots for large birds that pose a danger to airplane engines.

Outside Amsterdam's Schiphol Airport, which is the fourth-busiest airport in Europe, rows of noise-deflecting hills about 10 feet high have been built to abate ground-level noise and vibration from jets in nearby communities under air corridors that line up with the airport's longest runway.

The wedge-shaped hills, spread over about 80 acres, were strategically placed using satellite-based navigation tools. They sit at right angles to the direction of the jet noise, bouncing much of it into the sky, the design team explained, instead of letting the noise travel for miles along lowlands that are as flat as terrain in the U.S. Midwest.

"It is possible to make living around airports more comfortable, and we are very interested in exporting our idea to other places,'' landscape architect Lodewijk van Nieuwenhuijze said Friday during a phone interview from the Netherlands.

The Buitenschot Land Art Park was created by van Nieuwenhuijze's firm, H+N+S Landscape Architects, and landscape artist Paul de Kort, based on the observation that areas got quieter after fields were plowed with deep trenches and the earth was piled up — something that farmers worldwide have known for centuries.

The park was completed last fall at a cost of about $4 million, using robotic excavating equipment that forms hilly grooves similar to a plowed farmers field.

De Kort, in addition to helping design the landscape of hills and ditches, introduced pieces of land art that include a "listening mirror." A visitor to the park who stands near the center of the large parabolic mirror can hear passing planes clearly, and the noise dissipates as the individual walks toward the edges of the mirror, van Nieuwenhuijze said.

The novel use of open space to create a high-tech buffer zone that redirects plane noise upward is not a cookie-cutter solution that can be applied to every situation, and van Nieuwenhuijze said his team's design is intended primarily for areas where planes overhead are climbing, with their engines running at high power, just after takeoff.

Yet the innovative project represents the latest effort by the Schiphol Airport Authority to be a good neighbor while growing the airport's business as a passenger and cargo hub. Schiphol is a "noise-restricted airport.'' That means, for example, that aircraft with older engines, classified as stage 2, are banned. In addition, the airlines pay surcharges, based on the noise category of each aircraft, over and above the regular landing fees. And 20 percent higher takeoff and landing fees are in effect between 11 p.m. and 6 a.m. daily.

"In this way we are encouraging certain air traffic to come to Amsterdam Airport Schiphol and discouraging other air traffic,'' the airport authority states on its website.

The policies could potentially serve as a model for O'Hare to resolve the contentious public debate in Chicago and the suburbs over what to do about the changing footprint of jet noise as more new runways come online.

The Chicago Department of Aviation's current master lease agreement with the airlines serving O'Hare expires in 2018. The renewal process offers the opportunity for the city to negotiate a tougher contract that includes provisions addressing future jet noise effects on city and suburban residents for almost the next two decades.

Regulations that have been in effect for almost 30 years at John Wayne Airport in Southern California, and elsewhere in the U.S., demonstrate that cities and states have the legal and moral authority to insist on noise relief and compensation for violations, some experts said, adding that perhaps more elected officials just need to show a commitment to use the powers.

"The process of renewing a master lease is an opportune time to try to up the ante on noise mitigation,'' said Joseph Schwieterman, a transportation expert at DePaul University.

"Airlines plan their fleets several years in advance, so airports can phase in higher standards gradually in ways compatible with the needs of airlines,'' said Schwieterman, a former analyst at United Airlines.

But Schwieterman said it's "a tricky issue,'' because the results are based largely on negotiating skill.

"Chicago has very little ability to simply impose new rules on flight noise since that would pre-empt federal law,'' which is designed to limit the ability of communities to impose stringent standards at the expense of the system as a whole, he said.

Near Schiphol, the hilly ridges at the Buitenschot Land Art Park are roughly the length of large-wavelength, low-frequency long-range rumbles. The park's acoustical design dampens the drone from planes, cutting jet noise pollution by a small but notable amount of 2 to 3 decibels since the park opened last fall, according to officials with the Schiphol airport authority and neighboring towns.

Plans call for building more noise-dispersing parks near Schiphol, located in one of the most populated areas of the Netherlands. A larger park would be needed to attain a more significant reduction of 10 decibels, officials said. The airport handles an average of 1,200 flights a day, less than half the daily total at O'Hare.