Modernizing flood protection: higher availability at lower cost

The Dutch water authorities in Rivierenland are responsible for the water balance in 38 municipalities with a total of around 950,000 inhabitants.

The pumping station in Nijmegen controls the water level in the rivers, so that citizens in Ooijpolder and Düffelt as well as the Lower Rhine polder areas are constantly protected from flooding.

The rising population and the resulting advance in urbanization lead to constant growth in urban infrastructures. When handling natural resources such as water, it is therefore no longer enough to simply consider local requirements and events. Consequently, cross-border water regulation is required in order to protect cities and communities from flood water and flooding.

As part of a project by the International Water Association, a total of 165 weirs and 135 channel pumping stations will be converted to modern technologies. This also affects the landmark pumping station in Nijmegen, which is operated by the local Rivierenland water authority. As part of a collaboration project between the Netherlands and Germany, the relay technology used to date here was replaced by a modern automation solution from Phoenix Contact.

A centrally installed RFC 470 PN 3TX controller now manages up to three large pumps. It reads out the frequency converter via PROFINET, so that the units can be constantly monitored. PROFINET IL PN BK DI8 DO4 2TX bus couplers, distributed across the system, permit various sensors and actuators to be connected via digital and analog signals. Simple diagnostic options assist employees in the event of a malfunction when troubleshooting, which increases the availability of the pumping station.

Employees must also be able to intervene in the process at any time during operation. To this end, a touch panel is installed in the control cabinet door. Here, all measurement and operating data is displayed clearly, and can be manually altered if required. Due to the high cost of a SCADA system, those in charge opted for the web-based visualization software, WebVisit. It communicates with the central controller via Ethernet and displays current information on the panel via web pages. As such, employees can call up current values of all pumping stations and weirs, via a secure VPN tunnel. This means a quick reaction is possible in the event of a malfunction. A standard was developed for the web page design as well as for the programming of the controllers and documentation. Engineering costs are reduced due to this simplification.

To constantly monitor remote systems, the most important measurement and operating data is now transmitted to the control center via the remote control protocol IEC 60870-5-104 in a failsafe and reliable manner. The central controller installed in the pumping station processes the control commands triggered by the control room and sends the current operating data back via the VPN connection. Should data transmission be interrupted, all information is issued with a time stamp and is stored in the memory of the RFC 470 PN 3TX. Once communication is restored, the controller transmits the data in the correct order to the control room.