‘Water villages’ on the River Mulde: Wasewitz, Canitz, Kollau
Drinking water from the river Mulde
The production of drinking water from the Mulde (Slavic: Milda = the rich in water) between Eilenburg and Wurzen has a long tradition. Since 1912, water has been extracted from ice-age gravel aquifer as bank filtrate at the Canitz waterworks and processed into drinking water. The Thallwitz waterworks followed in 1943. Together with the Naunhofer waterworks, these facilities provide the majority of drinking water to the more than 720,000 inhabitants of Leipzig and the surrounding area.
Groundwater protection for the best drinking water
Around 1900, the city of Leipzig commissioned the engineer Adolf Thiem to search for water to supply the city. He found it in the local Mulde floodplain. In 1907, long before the two waterworks in Canitz and Thallwitz went into operation, Leipzig City Council acquired the necessary protected area for the water catchments, including the local farms: the farmers became tenants of their former farms. Since 1994, these areas have been managed ecologically by Wassergut Canitz GmbH to protect the water resources, thus avoiding harmful inputs into the soil and costly water treatment. The ‘water villages’ Canitz, Wasewitz and Kollau thus play an important part in protecting the groundwater in the water protection area with its filter well systems.
Mulde gravel superfilter
Before precipitation and Mulde river water reaches the glacial gravel-sand aquifer in the subsoil, it passes through various layers of soil that filter out pollutants and release minerals into the water. In Canitz and Thallwitz, the water must pass through fine alluvial deposits and up to 25 metre thick gravel beds. Due to its purity, this groundwater has been in demand as drinking water for more than a hundred years.
The geological history of the Mulde
Deposits of a ‘Ur-Mulde‘ can be traced back to the Tertiary period almost 35 million years ago. However, it was only around 350,000 years ago during the Pleistocene (Ice Age) that the current Mulde riverbed was formed. Before the Saale glaciation, the river, coming from Colditz, turned north-west along the inland ice front towards Naunhof. It was only around 130,000 years ago that the Mulde breached the barrier of the glacial moraines near Grimma and has been flowing northwards towards the Elbe ever since. The old Mulde riverbed in the direction of Leipzig or the Weisse Elster is now occupied by the Parthe river.
Water on our planet Earth
Almost three quarters of the Earth is covered by water. As a result our planet appears blue when viewed from space. Most of the fresh water that is vital for us humans is trapped as ice in the glaciers and polar ice caps. Only the smallest part is found in groundwater, lakes and rivers or in the air. If the earth were the size of a basketball, all the fresh water would fit into a grain of puffed rice. The cycle of evaporation and precipitation ensures that water is not lost from the earth. On average, around 70 cubic metres of water per second flow down the Mulde towards the Elbe and the North Sea.
Captions
- Canitz with the waterworks in the Mulde floodplain and the Hohburg porphyry mountains in the background.
- Principle of water extraction as bank filtrate.
- Canitz waterworks with ecological management of the water protection areas.
- Adolf Thiem (1836-1908): Developed the first Leipzig groundwater map in 1878 as a hydraulic engineer.
- The ‘water villages’ Kollau, Wasewitz and Canitz in the Mulde floodplain.
- Quality monitoring of the extracted water volumes.
- Layering and age of the rock strata in the Mulde area near Wasewitz.
- The course of the Mulde at the Oelschütz ‘Loreley’: Gravel sands of the Mulde (left) over porphyry rock (right).
- The Mulde River channels from the Late Tertiary to the present day; simplified according to geological research results by L. Eissmann.
- Our blue planet Earth.
Imprint
Concept and texts: In cooperation with Leipziger Wasserwerke; photos/schematics: Leipziger Wasserwerke, Archiv Geopark Porphyrland e.V., Colourbox, wiki commons, J. Rascher; geological section and maps: GEOmontan GmbH Freiberg after Leipziger Wasserwerke, Büro Schneider & Partner Bielefeld, L. Eissmann 1969/97, GK50dig 2005, Landesvermessung Sachsen; design: Lars Hoschkara, DESIGN & MULTIMEDIA (Wermsdorf)