It is fairly common in many parts of the world to see rabbits hopping about the grassy areas of an airport while passenger jets taxi nearby but Chicago O’Hare has taken this to the next level entirely by encouraging a wide range of ruminants to keep the airport’s grass in check. In fact, a cardboard cut-out of one of O’Hare’s llama population became the star of this week’s Airports Going Green conference in the city.

In August 2014 the Chicago Department of Aviation (CDA) re-introduced its grazing herd, comprising goats, sheep, llamas and burros from the nearby Settlers Pond animal rescue centre, to start working on up to 120 acres of land on several sites on O'Hare property. All the sites are located in areas away from or separated from the airfield by security fencing. The sites include hilly areas along streams and roads overcrowded with dense scrub vegetation that's difficult to maintain with traditional landscaping equipment.

“With nearly 8,000 acres of property, O'Hare has a very diverse landscape that includes areas that can become overgrown, particularly during the later summer months….,” says the airport. “This year the CDA has expanded its partnership with USDA Wildlife biologists at O'Hare, who work at O'Hare year-round. The staff will quantify the results and benefits of the grazing herd on airport property. In addition, the CDA has added a new partnership with the 4HYouth Program at the University of Illinois Extension in St. Charles, Illinois, to involve students in the care of such rescue animals at Settlers Pond.”

The grazing herd programme is part of the CDA’s Sustainable Airport Manual (SAM) strategy. A more recent example of SAM initiatives is the November 2014 agreement with a private company to develop a 4,000-square-foot fueling station and travel center featuring a range of alternative fuels and food options on City-owned vacant land near O’Hare. The travel centre will offer compressed natural gas (CNG), biodiesel and fast-charge charging stations for electric vehicles, as well as conventional gasoline. The project is expected to create 73 construction jobs and 30 permanent positions. The CDA will receive a base rent of $100,000 for the land and 5 percent of gross sales.

According to the CDA: “The travel center will be built and operated by PMG Airport Developers [www.pmgairport.com], builder and operator of cutting-edge travel plazas at airports across the country, and Clean Energy Fuels, the nation’s leading provider of CNG, LNG and Redeem renewable natural gas (RNG) for transportation, with nearly 500 stations. The target opening date for the travel center at O’Hare is early 2016.”

In addition to environmental benefits, alternative fuels like CNG can deliver economic benefits. CNG costs up to $1.50 less per gallon than gasoline or diesel. In addition, natural gas engines can be up to 50% quieter than traditional diesel engines.

The Chicago Sustainable Airports Manual has gained fame amongst the North American airports community, with Chicago hosting an annual Airports Going Green conference at which airports from across the continent – and the world – share best practice tips on airport and airfield sustainability.