Photo Gallery: From Open Sewer to Nature Oasis 11/16/2012
  In order to keep the sewage flowing, the main pipe has to have a downward...
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In order to keep the sewage flowing, the main pipe has to have a downward slope of 1.5 per mill, meaning it drops 1.5 meters for every kilometer in length. In order to make this possible, the slurry stream needs pumping stations. Plans call for building three of these colossal water elevators.