The Landeswasserversorgung has always strived towards meeting the increasing demands for water by expanding the collection pool systems in good time. The development of water delivery made it possible to identify at an early stage when the ground water source in the Donauried would no longer be able to meet the growing demands of the consumers by itself.
In 1929 the Landeswasserversorgung showed great foresight in purchasing a large karst source, the Buchbrunnenquelle, in the Egau valley near Dischingen in the eastern Swabian Alps. The flow of the Buchbrunnenquelle is between 600 and 1400 litres per second and forms the main tributary of the small Egau River, rising near Neresheim.
In 1952, after comprehensive exploratory measures, the Landeswasserversorgung decided to use the Buchbrunnenquelle as the supply of drinking water to the public. On the basis of a state contract between Baden-Württemberg and Bavaria, the right of extraction was set at up to 800 litres per second, depending on Egau water flow conditions. In 1957, the Egau Waterworks started operations after a construction period of four years.
By nature, the karst spring water from the Buchbrunnenquelle is of very high quality. Only after long-lasting heavy precipitation and during the periods of snow melting does mineral clouding of the spring water occur.
With the construction of the A7 motorway through the water protection area, the treatment plants in the Egau Waterworks had to be enlarged as a preventative safety measure between 1982 and 1984. So as to be able to provide Landeswasserversorgung customers with softer drinking water, a decarbonising system was built onto the Egau Waterworks between 1993 and 1995 after the positive experiences made in Langenau Waterworks. The system softens the karst spring water down from its natural hardness of 18.5°dH (due to the surrounding geological conditions) to around 13.5°dH.
Process diagram of the Egau Waterworks treatment plant
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