Making Lake Constance Visibly Cleaner
Eriskirch is located directly on Lake Constance, Europe’s largest drinking water reservoir. In the 1970’s this unique natural resource was threatened by eutrophication due to acute phosphate contamination. The problem was immediately addressed by a number of remedial measures, the key one of which was the Eriskirch clarification plant.
As Harald Schäfer, Environmental Minister for the German state of Baden-Württemberg at the time, explained:
"With the start-up of this first flocculation-filtration unit on the shores of Lake Constance, the Wastewater Association of the Lower Schussen Valley demonstrates their firm commitment to keeping environmental water clean.” Meeting all expectations, the plant’s seven DIN 19605-conformant EVERZIT® N multilayer filter units dramatically reduced phosphate concentrations to trace levels of only 0.1 - 0.2 mg / L. The resultant improvement in water quality in the mouth of the Schussen river, i.e. where it flows into Lake Constance, was noticeable to the naked eye.
Used as the upper layer in these multilayer filter beds, EVERZIT® N increases treatment capacity and reduces operating costs by providing specific benefits:
|Capacity of Filtration:||approx. 1800 m³/h|
|Number of filters:||7 open dual media filters|
|Total surface:||155 m²|
|Filtration velocity:||approx. 12 m/h|
|Filter material||Height||Grain size|
|EVERZIT® N:||850 mm||1.4 - 2.5 mm|
|Quartz sand:||650 mm||0.71 - 1.25 mm|
|Quartz gravel:||150 mm||2.5 - 5.6 mm|