The German airport that saved Berlin now divides the city

BERLIN, Germany — On a rare sunny afternoon in May, Berliners in short-shorts and bikini tops loll in the grass between the runways at Tempelhof Airfield, the iconic airport that kept the city's isolated western-controlled zone alive when the Soviet authorities blockaded the city in 1948.

On the tarmac, a line of bicyclists zips past a jogger doing laps, while in the center of the otherwise barren, 300-acre field, gardeners water plants.

“It's incredible,” says 31-year-old Katharina Hohmann, smiling and suntanned, with a toddler playing in the grass.

“The people have developed their own things here, so it's very peaceful and very creative.”

Perhaps not for long.

Closed in 2008 after a public referendum calling for it to be kept open failed to attract enough voters, the neglected Nazi-era airfield has spontaneously evolved into one of the world's strangest city parks: flat, treeless and crisscrossed with runways and floodlights.

But on Sunday, the airfield-turned-park faces another fight for its identity, this time in the form of a public referendum to block plans for a public library and real estate development on the site.

In 1948, Tempelhof helped prevent the Allied-controlled portion of Berlin from becoming part of the Soviet empire, facilitating nearly 300,000 supply runs by the American pilots of the legendary airlift called “Operation Vittles.”

While there are few reminders of the airfield's historical importance on the site, it's part of a battle for the future of the city.

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The government's plan would transform Tempelhof from a vast, grassy field into a mixed-use development of apartments, shops, sports fields and a lake.

The Berlin Senate argues that the development will retain some 230 out of 300 acres as open space, and that new apartment buildings are needed to keep pace with an economic boom that’s driving up rental prices across the city.

Opponents of the project, including a citizen's initiative called “100 percent Tempelhof Feld,” are suspicious that the apartments reserved for so-called “middle-income” residents will soon skyrocket in price and the development will speed gentrification of the surrounding neighborhood.

The group gathered 185,000 signatures in order to get the referendum on Sunday's ballot, along with candidates for the European Union parliament elections.

“Affordable housing is not social housing,” says volunteer Nora Salas-Ellanes, who argues that if the government were sincere, it would define its terms more clearly and write them into the development plans.

“[The rental rates are] not ensured, and not guaranteed by law. It's just a saying.”

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A recent poll suggests that Berliners — who largely see gentrification as the main threat to their laidback lifestyles — oppose the government project by a 54 to 39 percent margin. But the city's beloved slacker attitude may be the initiative's biggest obstacle in fighting city hall.

To block the government's plan, the referendum requires not only a majority of votes, but a quorum amounting to 25 percent of eligible voters. The same requirement killed the 2008 referendum to keep the old airport running, as well as a referendum in November that called for the city to buy back its electricity grid in the wake of escalating prices.

“Just because we’re winning,” says Salas-Ellanes, “doesn't mean we will win.”