The impact of bad sensors on the water industry and possible alternatives

Advanced monitoring of water quality in order to perform a real-time hazard analysis prior to Water Treatment Works (WTW) is more important nowadays, both to give warning of contamination and also to avoid downtime of the WTW. Downtimes could be a major contributor to risk. Any serious accident will cause a significant loss in customer and investor confidence. In this paper, two treatment plants (case studies) were examined. One was a groundwater WTW and the other a river WTW. The results showed that good correlations existed between the controlling parameters measured at the river WTW, but not at the Groundwater Treatment Works (GWTW), where there was a lack of good correlation between warning parameters. Results emphasised the value of backup monitoring and self-adjusting automation processes that are needed to counteract the rise in power costs. The study showed that a relationship between the different types of sensors and/or measured parameters can be deduced in order to cross-check the sensors performance and be used as a guide to when maintenance is really needed. Operating hierarchal procedures within the WTWs could also be used to cut costs, by improving condition monitoring. Both of the case studies highlighted the need for new non-invasive/remote sensors and some new investment in information technology infrastructure.

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