The Referendum “Berlin braucht Tegel” that aims at keeping the Airport Tegel open for operation obviously just managed to collect the necessary number of signatures. Almost 200.000 Berliners singed the petition that would make such a referendum possible.
Originally a law would force Airport Tegel to close once the new Berlin Airport BER would be fully functional. But it becomes more and more obvious that the new Airport will probably be already too small, when it’s finally opened. And currently nobody really knows anyways, when the Airport will actually be opened. It should have first opened in June 2012 – currently it is unclear if the Airport will open in 2018 or not.
Based on the article “Initiative Berlin braucht Tegel – Volksbegehren für Flughafen Tegel hat genug Unterschriften” (tagesspiegel.de)