Introduction


In tomorrow’s smart cities, not only the resource efficient movement of goods and people will be of highest importance. Amongst the most important areas will also be the monitoring of water quality. In a smart city every resident will have real-time access to parameters like indoor air quality, fastest commute route including locations of shared electrical vehicles. It is s::can’s strong belief that the quality of each and every tap water supply will be amongst the most important parameters.
In Belgium, the pipe::scan and the micro::station are used to monitor the drinking water network. Up to 10 parameters are measured simultaneously and s::can’s event detection system helps to safeguard the water at all times.
Challenge
Farys|TMVW is a Belgian drinking water company supplying drinking water to the coast area which is produced in the central part of the country. For this, water is transported in large pipes over more than 100 km. To ensure high water quality, Farys|TMVW decided to install online water quality sensors. These online sensors should ideally be capable of measuring a wide range of relevant quality parameters complementary to the legal routines. Maintenance should be limited, and in places where less space is available, an in-pipe solution was required.


s::can’s solution
The s::can micro::station and the pipe::scan are the ideal products as they measure multiple parameters simultaneously and require little maintenance. The pipe::scan is installed inpipe, the micro::station can be installed next to a conventional sampling line.
The pipe::scan is a sensor system for monitoring drinking water quality in pipes under pressure. It measures up to 10 parameters in one device: TOC, DOC, UV254, Turbidity, Color, Chlorine, pH/redox, Conductivity, Temperature and Pressure. The water quality data can be sent to any central database via almost any protocol. The possibility for the pipe::scan to support several probes, makes it a perfect alternative for a micro::station for inpipe applications.
The fully modular micro::station combines several s::can instruments to a compact and versatile system. The s::can micro::station is designed for online monitoring of water quality parameters in clean media, such as drinking water. The components are factory assembled with all required flow cells, mounting fittings and pipework on a compact panel.
Benefits
One of the greatest benefits of the s::can products is the event detection system that gets the most out of the acquired data by learning to recognize how water quality changes dynamically over time. When an abnormal change occurs, an alarm signal is sent to the SCADA system to warn the operators.


Figure 1 shows the effect of maintenance works on water quality: A reservoir was filled from an alternative production plant. The water from that production plant has a higher conductivity (around 850 μS/cm) than the water produced in the production plant usually filling the reservoir (around 450-500 μS/cm). The switch occurred at 01:00 A.M. on 21/12 and the change in the conductivity is clearly visible in the line graphs of the data measured by the s::can condu::lyser.
The changes in the water quality described in Figure 1 were quickly picked up by the ana::tool software and a pattern alarm was triggered 3 hours and 30 minutes after switching. Pattern alarms are connected to the SCADA system to warn the engineers of water quality changes. During this period the water quality complied with the Flemish and European drinking water standards at all times.


Furthermore, the simultaneous online measurements of UV254, TOC, DOC and free chlorine are useful to steer chlorine dosage and to mitigate the formation of disinfection by-products. In combination with online microbiological monitoring by Farys|TMVW the s::can data offers valuable insights in the behaviour of the drinking water quality during distribution.