When walking through the main station in Zurich, you’d be forgiven if your nose started to crinkle. For the last few weeks, parts of Zurich Main Station have possessed a highly unpleasant smell. Officials from Swiss public transport have now acknowledged the problem and pledged to solve it.

Löwenstrasse underpass in Zurich has an unpleasant odour

For the last few weeks, there has been a continual and penetrating smell in the Löwenstrasse underground section of Zurich Main Station. “It stinks and is really gross. You usually smell something like that in subway stations in warm countries,” one commuter told 20 minuten.

The worst of the smell can be found in the entrances around platforms 31 to 34, with the odour said to get more pungent when the weather is at its hottest. According to 20 minuten, many commuters have now chosen to avoid the underground section whenever possible.

Why does Zurich Main Station smell so bad?

According to Blick, the main reason for the horrible smell in Zurich HB is the new FV Dosto trains used for travel between Swiss cities. In order to process wastewater from toilets on board, the train filters out and safely disposes of solid components, and then sends the water through a bioreactor filter before being disposed of on the rails in the station.

The problem is, the bacteria used to eliminate the smell of the water are no longer strong enough to destroy the entire stench, particularly in periods of high demand such as during rush hour. A combination of weak bacteria and hot weather are the reasons why the smell on the platforms is so bad. 

SBB now working to solve the bad smell in Zurich HB

SBB admitted this back in July, with a spokesperson noting at the time that “SBB employees are busy adding a lot of fresh bacteria to the overloaded bacteria." Now that passenger numbers are up, and the country is regularly visited by heatwaves, the stench is now unbearable in some places. 

On billboards around the station, SBB acknowledges the "unpleasant smell in Löwenstrasse station" and said they had "intensified cleaning" to "fix the cause as soon as possible." Speaking to Blick, SBB spokesperson Martin Meier said that "all surfaces in HB Zurich are cleaned several times a day. Even the track bed gets a wash cycle, and the underground stations Museumstrasse and Löwenstrasse [are washed] several times a week.” Sadly, so far, the smell remains ever-present.