The control system of water management in the large district town Öhringen

Water supply, wastewater treatment and flood protection in just one control system: HST achieved this objective in the district capital of Öhringen, which was experiencing problems with its process control system at the turn of the millennium. The system dating back from 1993 could not be documented from 1.1.2000, the switching moment to the new year. An update of the software was too expensive, and the spare part procurement was only possible for a short time. As a major concern, the controlling function of the entire waterworks could have been at risk if no action had been taken.

Another concern is the problems in the telecontrol of the sewage treatment plant. In an attempt to connect other rainwater overflow basins to the telecontrol system of the sewage treatment plant, the system collapsed completely. What followed was a demand for a sufficient inventory of water supply and wastewater treatment area. It soon became clear that a great solution for the process control technology of both areas and flood protection was expected. During this time, the operators visited numerous municipalities to investigate the range of services offered by various control systems.

Ultimately, SCADA V10 was chosen in Öhringen because the estimated amortization for the control system of water management turned out very positive. For example, the planned installation of measuring equipment in the water supply network has been estimated to reduce pipe network losses to, not only four, but at least eight percent while the average of pipeline losses in the period from 1993 to 2004 was 13.7 percent.

The annual operating costs of the wastewater industry have also been calculated in terms of monitoring savings. After all, regular monitoring is a legal obligation, so any neglect leads to criminal consequences. According to the calculation, if manual monitoring is changed to the control technology, control will be automatic in the future and thus better. And so much in advance: All these expected effects occurred.

The changeover to the control system took place from 2006 to 2010 and was updated in 2017 to the current version SCADA V10. The focus was on the security of the systems. HST worked with redundant systems that synchronize data and reports at both the local level (in the individual plants) and the paramount level (between the individual plants).

Thanks to the control system, the operators are now in a comfortable position to keep the entire overview. Pipe breaks can be installed quickly and in critical conditions, the system immediately sends an alarming message. In addition, the rain overflow basins are controlled by SCADA V10 and the performance of the treatment plant is monitored. In flood protection, safety reports are created and the realtime data of water levels can be viewed online on a city website.