Swimming baths, Rheinmünster

Schell shower panels and Water Management System help maintain drinking water hygiene

After contamination with Legionella was discovered in the female and male showers during a routine inspection in early 2020, the swimming baths in the Greffern district of Rheinmünster had to close. This was a loss for the town that Mayor Helmut Pautler simply refused to accept. Accordingly, he made every effort to ensure that this popular facility could be retained – not least because the closure had put a stop to school swimming courses.

Project data

Opened: 1976

Swimming pool with 29 °C water temperature, various courses, infrared cabins

Most recent renovations: 2020

SCHELL products: Water Management System SWS, LINUS DP-C-T shower panel, BE-K wired bus extender

The main issue to be tackled by this renovation was the mixing station for shower water: housed in the basement, this was original to the building when it opened in 1976. To date, this mixing station has been responsible for heating both potable and non-potable water for the showers in the baths and the adjacent sports hall to 40 °C, and then pumping it upwards: an ideal breeding ground for Legionella.

The old mixed water installation was removed and has been replaced by a new and more advanced system that produces hot water at 60 °C. Water is no longer routed to the showers using a mixed water line but instead via two separate drinking water mains for cold and hot water. The old concealed shower fittings have been replaced by 17 of Schell’s LINUS DP-C-T electronic exposed shower panels. These enhance the overall visual appeal of the shower area while improving comfort for users and offering easy maintenance via the service flap. A key feature of the Schell LINUS DP-C-T shower panels was also the main reason for choosing this product: thanks to the integrated thermostat, hot and cold water is now mixed to an agreeable temperature in the shower panel itself. This short route from heating to actual usage by visitors to the baths hugely reduces the risk of Legionella.

Automated support for maintaining the installation’s specified normal operation

Since the swimming baths were reopened in autumn 2020, all showers are now flushed automatically, which simulates specified normal operation while ensuring the regular, full and documented exchange of water in the installation. A second solenoid valve in the shower panel also offers the option of conducting a thermal disinfection with hot water at 70 °C, to kill off any potential bacterial contamination. The central control and documentation (logging) of stagnation flushes and thermal disinfections is handled by the Schell SWS Water Management System. In this case, project developers decided to use the system’s wired variant: bus cabling was run between the individual sanitary facilities and each of the 17 shower panels was connected up. Data can now be read off at any time and parameters can be adjusted accordingly. At the heart of the system is the SWS Server with its intelligent software, responsible for handling the centralised adjustment of fitting parameters, stagnation flushes, thermal disinfection runs, and all analysis and record-keeping. All flush times have been configured as specified by the planning engineers, with multiple shower panels consolidated into flush groups. Thanks to SWS, the individual piping sections and shower fittings can now be flushed automatically at a high volume flow rate, which decisively reduces the risk of biofilm formation and Legionella growth in piping, making technician callouts to the facility less likely and simplifying maintenance planning.

“All project work has been completed to ensure that it does not need to be tackled again during the medium-term general renovation of the baths,” emphasises Mayor Pautler. For Pautler, durability is therefore an important goal, since renovations to the potable and non-potable water installations here in Rheinmünster are just the first step. All of the technical systems, together with parts of the building envelope, have still to be renovated here at the baths. When this happens, the existing Water Management System SWS can then be upgraded to facilitate the networking of other electronic Schell fittings (using either wired or wireless connections) – on wash basins, WCs and urinals. Only Schell currently offers this option of combining wired and wireless units in a single water management system.