The Roetgen Drinking Water Treatment Plant

The Roetgen drinking water treatment plant is operated by the Wassergewinnungs- und -aufbereitungsgesellschaft Nordeifel mbH (WAG) and can treat a maximum of 6,000 m³ of drinking water per hour, making it one of the largest ultrafiltration plants in the world. In total, 28 million m³ of water are treated every year. The Roetgen drinking water treatment plant was built in 1953 and extended in 1971 with a two-stage, open rapid filtration. In 1995 the decision was taken to expand the Roetgen drinking water treatment plant in order to ensure that high quality drinking water could be produced at any time. The new plant uses membrane filtration techniques and also includes the existing plant components. The plant was ready to be put into operation in December 2005.

The untreated water is taken solely from the dams in the Northern Eifel. The Roetgen drinking water treatment plant can collect untreated water from a total of three dams connected by pipelines and tunnels.

After setting the pH value and adding the flocculent aluminium sulphate, the water is fed through to the membrane plant. Ultrafiltration membranes with a pore size of 0.02 µm are used. In total, a membrane surface of approx. 70,000 m² has been installed in the plant. An equally high water quality can be guaranteed at all times, especially with regards to hygiene and even starting from poor untreated water conditions.

After passing through the membrane stage, the pH value is raised by adding sodium hydroxide, before the water is fed to an open rapid filter with a filtering surface of 1,170 m². A limestone filtering material is applied in this filtering stage, which is used to retain iron and manganese and harden the drinking water. The treatment process is completed by adding chlorine dioxide to disinfect the drinking water.

The Woffelsbach wastewater treatment plant

The Woffelsbach wastewater treatment plant is operated by the public water authority Eifel-Rur (WVER) and is located next to the Rursee Lake. The innovative membrane bioreactor was ready to be put in operation in 2005 and has proved to fulfil the specific conditions at this location. These are, for example, the limited amount of space and the high quality demand upon the treated water. The effluent is discharged in the Rursee Lake, which is used for recreational activities.

Another characteristic of the Woffelsbach wastewater treatment plant is that the wastewater from one of the sites in the catchment area is transported through a pressurised pipeline, which runs on the lake bed of the Rursee Lake.

The plant is configured to treat the wastewater from 6,200 PE and the daily wastewater inflow amounts to 1,860 m³/d. The mechanical and biological treated wastewater is dispensed to six separate filtration compartments. Each of them is equipped with seven membrane modules. The total membrane area is 13,440 m². The flat sheet Kubota membranes have a pore size of 0.4 µm. The suspension of activated sludge and water is separated by the filtration process. The purified water is largely free from suspended solids and pathogen bacteria.