Berlin’s sewage farms peaked in 1928: at the time, sewage farms covered an area of 10,000 hectares. However, not all of the 20 sewage farm districts were located within the city limits, also spilling over into the surrounding areas of Berlin. In 1992, the final year of data collection, only five sewage farm districts remained that treated wastewater using this natural process: portions of the Karolinenhöhe, Sputendorf, Großbeeren, Deutsch-Wusterhausen and Wansdorf sewage farm districts. At this stage, a significantly lower volume of wastewater was discharged into the fields than in the 1970s, mainly due to portions being removed from operation.
The sewage farm concept: wastewater seeps away slowly if introduced to large areas. Nutrients and pollutants remain in the upper layers of the soil. Vegetation and rock layers act as natural filters. The filtered water seeps into the groundwater and is thus returned to the cycle.
The construction of sewage treatment plants significantly reduced the area used for sewage farms: in 1992, only about 1,250 hectares of land were still used as sewage farms. Former sewage farms were now used for agriculture purposes or as recreation areas. This is the case for Karolinenhöhe, where some parts have become landscape conservation areas.
Dive into the history of Berlin’s sewage farms on the following pages. The relevant map illustrates the areas and their use.