I live in a city with its own special breed of traffic jams – traffic that gets so snarled, it has its own label: stau. Cologne, a city of 1 million people, its geography divided in two by the Rhine River, can sometimes have traffic so backed up that it’s faster to bike across the bridge than to hop into a car.

What’s amazing about this traffic is just how unnecessary it is. With subways and railways that stretch into every crevice of the nearby suburbs and neighboring cities (Duesseldorf and Bonn are less than 30 minutes by train, though I wouldn’t dare call them suburbs of this city for fear of flogging), you can often get door to door faster by train than by car. As home to Europe’s largest train station, too, you can get nearly anywhere on the continent at any time (my New Year’s trip to Paris was cut from 5-1/2 hours by car to 4 hours by the 200 km/hour Thalys train).

Still, people – especially those on the outskirts of the city, are attached to their cars. So starting on January 1, the city of Cologne implemented a new commuting policy to help combat emissions. Though it doesn’t limit the number of cars allowed into the city (a dream of mine since the first time I tried to ride my bike through the city center) and it’s not the same as the toll system London and now Milan have introduced, it does keep the heavy polluters out of the city.

Now, in order to drive into Cologne, you have to have a sticker saying your car is not a polluting vehicle. This is more than just an emissions test… it ranks the levels of emissions that technically road-worthy vehicles produce (I say technically because I’d never consider a 4-wheeler a proper vehicle, but they are allowed out of the woods here, don’t ask me why). Which means autos that pass looser emissions tests in the ‘burbs may not be allowed into the city. Not ever. And those that are on the borderline may not be allowed in on smoggy days. Though in an ideal world, those cars wouldn’t be spitting their smoke out in the suburbs either, I’m happy that my hometown’s doing a bit more to clear the air.

FYI - For all those arguing against a similar policy in the States, in the first week of the pass’s usage, the staus didn’t increase and everyone still got to work on time. Fighting smog this way isn’t as problematic as you might think.