From Monday 28 August until probably Friday 1 September 2006, Stadtwerke Gießen AG (SWG) will be testing the newly installed chlorine system at the Queckborn waterworks. During this time, SWG will be adding chlorine to the water it pumps from Queckborn. The chlorination affects the water network in the entire city of Giessen with the exception of the districts of Lützellinden, Allendorf and Rödgen as well as parts of Kleinlinden. These districts are not supplied with water from the waterworks in Queckborn. Also affected by the chlorination is the water supply to the Grünberg districts of Queckborn and Harbach as well as the supply area of the Tannenköppel elevated tank of the city of Grünberg.
Customers can continue to use the water as normal
Despite the chlorination, SWG customers can continue to use the water as normal. After all, the Drinking Water Ordinance expressly stipulates chlorine as a disinfectant and prescribes a maximum value of 0.2 mg chlorine dioxide per litre after treatment. SWG will of course adhere to this maximum concentration. "As a result of this test run, our customers may notice a slight odour of chlorine when they turn on the tap," says Peter Keller, Head of Gas and Water Systems Engineering at SWG.
Investment in the safety of the drinking water supply
Peter Keller continues: "With this test, we want to make sure that the chlorine system works perfectly in an emergency, i.e. if the water is contaminated with bacteria or viruses. Of course, we do everything we can to ensure that such an emergency does not occur in the first place. But no water supplier can completely rule out this risk. The approximately 40,000 euros that the new chlorine system cost us are an investment in the safety of the water supply. "
Conversion of the Queckborn waterworks
Over the past few months, Stadtwerke Gießen has completely modernised its waterworks in the Queckborn district of Grünberg. Among other things, a deacidification system was installed. The previous chlorine system was not compatible with this technology. A new system for adding chlorine therefore had to be installed.
And this is how the system works
The new chlorine system works according to the so-called acid-chlorite process. Diluted solutions of sodium chlorite and hydrochloric acid are mixed in a specific ratio. The chlorine dioxide produced during this reaction is dosed into the drinking water in proportion to the water flow rate using dosing pumps. Depending on where contamination is detected, the chlorine dioxide can be fed into the water network at the Queckborn waterworks via one of the three transport pipes: to Giessen, Grünberg-Harbach and Grünberg-Queckborn or to the Grünberg Tannenköppel elevated tank.