Challenge
Nine waterworks ensure the supply of drinking water in Berlin. The Berlin drinking water comes from urban groundwater sources that formed in rock more than 10,000 years old. Ideal geological conditions, extensive protected water areas and a strict precautionary principle ensure the highest water quality. From about 650 wells with a minimum depth of 30 and a maximum depth of 174 metres, the Berlin groundwater is first pumped to one of the nine waterworks of the Berliner Wasserbetriebe. There, the water is treated and then stored in pure water tanks. Berlin households, industry and commerce need a daily average of approx. 535,000 cubic metres of fresh drinking water. Up to 1.1 million cubic meters per day, which is almost double the amount, can be provided.
The water supply of the city of Berlin is monitored and controlled from the control rooms of the three leading waterworks Friedrichshagen, Tegel, and Beelitzhof. High production capacity, the coordinated interaction of the waterworks and their central management eliminate supply bottlenecks. The waterworks Beelitzhof is one of three focus waterworks. It works in conjunction with the plants in the southwestern part of the city. The waterworks is located on the Wannsee. It includes 80 wells that extend along the banks of the river Havel. The waterworks feeds approximately 35 million cubic metres of drinking water annually into the Berlin network.
Under normal circumstances, the water requires no post-treatment. However, in very rare cases the water must be disinfected.
Solution
The installation of a chlorine gas dosing system was a clear choice for the water works. Berlin Wasserbetriebe has been using Wallace & Tiernan® systems for decades and as a long-term service customer they trust the safe, trouble-free operation of the systems and plants. The chlorine solution is made of chlorine gas in a chlorine plant and is routed to the dosing points through dispensing lines, which are partially buried in the ground and partially installed in the building. The 2013 installed chlorine plant is housed in two rooms: the chlorine dosing equipment and the control cabinet are located in the chlorine dosing room; the required chlorine gas is stored in the chlorine room. The latter is monitored by a chlorine gas detector.
Results
Chlorine for disinfection is added only in case of an emergency. The concentration is so low that the disinfectant dissipates on its way to the consumer and is thus no longer perceptible. The control and regulation of the entire system is carried out via a central control cabinet with an embedded process control system. High quality drinking water is always guaranteed.