MicrobialSensors4Water

• Analyzing unchlorinated drinking water quality using multiple microbiological sensors
  Jentina Schuurman, Project leader Water Expertise Centre Vitens
  Vitens has carried out many projects in which the water quality of unchlorinated drinking water is monitored using microbiological sensors. The first sensor was tested back in 2013 and sensors are still being tested. Testing and putting sensors into production does not always go without a struggle. I would like to share Vitens' experiences with installation, testing and the putting into production of sensors and the challenges we still face today.
   
• Severn Trent’s experience with online flow cytometry
  Matthew Ward, Severn Trent
  Severn Trent has deployed online flow cytometry at some our water treatment works providing round the clock monitoring of bacteriological performance at the disinfection stage of the treatment process.
  In this presentation I give an overview of Severn Trent’s application of online flow cytometry, highlighting some of the challenges faced and solutions developed, particularly around remote data acquisition which has given us the ability to collate data from multiple instruments for analysis.
  General observations seen including seasonal changes and the impact of changes in disinfection parameters will be discussed along with examples from specific sites. Finally, I will discuss the next steps and future plans for online flow cytometry at Severn Trent.
   
• The use of flow cytometric fingerprinting in microbial water quality monitoring
  Fien Waegenaar, University of Gent
  Safeguarding microbial water quality remains a challenge for drinking water utilities, and because of population growth and climate change, new issues arise regularly. To overcome these problems, high-resolution online microbial monitoring during treatment and distribution could prove essential. In this presentation, the applications of online flow cytometry and flow cytometric fingerprinting will be discussed. Online flow cytometry is a sensitive, fast and consistent way to evaluate drinking water quality at critical control points. Case studies from pilot-scale and full-scale drinking water distribution networks will be shared to show the added value of phenotypic fingerprinting in the detection of unwanted contaminations and water quality changes.

10.45 - Coffee-break

• Use of high-frequency automated bacteriological monitoring to follow the dynamics of surface water quality
  Sophie Haenn, Eaux de Paris
  Monitoring the micraobiological quality of surface waters is an important issue for many water stakeholders. Indeed, the rapid detection of contamination of these waters is important both for purification treatments but also for other activities around surface waters, such as, for example, recreational or bathing events.
  Fecal contamination, monitored by bacterial indicators (E.,.coli and enterococcus), is a major issue for microbiological quality and their fast detection is essential. Quantitative measurements are essentidl for classification of bathing waters according to the European Directive 2007/6/EC.
  When regulatory monitoring is based on single samples analyzed in the laboratory within 24 to 48 hours, the challenge of detection as fast as possible.
  Online microbiological sensors have appeared on the market. Depending on the technologies used, results from online methods can be obtained between 15 minutes and 9 hours after sampling, allowing a high frequency monitoring. We will present the long-term usage of this type of monitoring in surface water.
   
• Automated quality monitoring – a Swedish perspective on challenges and way forward
  Markus Fröjd, Sweden Water Research
  Sweden is facing large challenges in the coming years related to climate change, an under-funded and under-performing renewal rate of critical infrastructure and increased legal requirements for quality monitoring. These challenges lead to the need for innovative and efficient microbial water quality monitoring solutions. These challenges, combined with organizational challenges unique to our organizations lead to the need for innovative and collaborative solutions to ensure the quality of our drinking water also in the future. In the project Källby water workshop, multiple monitoring solutions have been tested and some have since been included in the daily operations of our utilities – how will we further develop these techniques and their implementation in the future?
   
• Microbiological near-real time monitoring of alpine karstic spring water resources
  Andreas Farnleitner, University Krems & TU Wien, ICC Water & Health Austria, & Lena Campostrini, Medical University of Vienna
  Alpine karstic spring aquifers are one of Austria’s main drinking water resources. Integrated management practices (catchment protection, selective spring water abstraction, treatment/disinfection) have been developed to ensure drinking water supply of highest quality. On-line near-real-time monitoring of (microbiological) spring water quality is one of the essential elements. Chemo-physical parameters, including spectral absorption coefficient at 254 nm and turbidity proved to be very robust on-line parameters to sensitively indicate near-real-time surface influence, including associated microbiological (faecal) contaminants. More recently, the potential application of direct detection of microbial contaminants by near-real-time technology has also become of increasing interest (e.g. on-line enzymatic detection, on-line flow cytometry, fluorescence spectroscopy). Besides giving a general overview on the applied microbiological near-real-time technology in selected springs of the Northern Calcareous Alps, the presentation will provide insights in the recent evaluation of flow cytometry-based long-term series (10+ years) and highly resolved summer periods, supported by event-triggered auto-sampling.

12.00 - Wrap-up morning session

12.15 - Lunch

• Comparison, validation, challenges and usage of online microbial sensors in recreational and drinking water
  Nikki Van Bel, KWR
  The current standard for microbiological (drinking) water quality is still primarily based on culture methods, which can take 24 (E. coli) up to 72 (Heterotrophic Plate Count) hours before a result is available. Also the frequency of measurements is low (e.g. daily or weekly). As a consequence, microbiological disturbances are only known after days and information on dynamics of the water system is missed.
  In the past decade rapid microbiological methods have been developed for automated online monitoring on site (sensors), all of them giving a result within minutes to hours. However, experience with sensors is limited making interpretation of the results and implementation of sensors challenging. In general sensors correlated well to laboratory methods, but this differed per water type, sensor and water treatment. Online tests with sensors at drinking water production sites showed that sensors can be used to measure several microbiological processes in the drinking water distribution system and production plant. However, applying and validation of sensors comes with many challenges and until now user experiences vary strongly. These aspects need attention to allow implementation of microbiological sensors.
   
• Autonomous monitoring of harmful algae in engineered and natural water systems
  Ameet Pinto, Georgia Institute of Technology
  The frequency and severity of harmful algal blooms (HABs) and their impact on natural and engineered water systems is being exacerbated by ongoing and legacy nutrient pollution coupled with climate change. Our ability to manage HABs and their impacts is critical depended on rapid and accurate monitoring of surface waters. Chlorophyll measurements and remote sensing may provide estimates of photosynthetic biomass, they do not provide any taxonomic resolution which is often critical from a decision-making perspective. Techniques and tools for taxonomic identification are either time consuming and/or require expensive instrumentation or specialized expertise and thus are not deployable at scale. To address this gap in the HAB monitoring landscape, we developed an autonomous low-cost microscope capable of capturing images of microalgae and classifying them. This system can group microalgae based on their phenotypic features and identify specific taxa, providing a high-resolution solution at a much lower cost.
   
• Do we really need online monitoring?
  Frederik Hammes, Eawag
  Online microbial monitoring technologies and applications for drinking water have developed tremendously during the last two decades, offering exciting research opportunities but also substantial challenges. My presentation will reflect on our development of online flow cytometry monitoring, from a basic idea to commercial applications. I will show different examples where online monitoring was critical in revealing dynamic processes and events in drinking water treatment and distribution systems, which were previously largely unnoticed with conventional monitoring. I will also discuss the integration/combination of online flow cytometry with other online sensors, and the potential value as a monitoring part of early-warning-systems. Finally, I will reflect critically on the use of online monitoring, differentiating between research and fixed applications, considering costs, operation, expertise, and the inevitable creation of data graveyards through over-analysis.

14.30 - Coffee-break

• Establishing a community of practise for the use of microbial sensors in water monitoring
  Corina Carpentier, Sensileau
  Microbial sensors are an advanced type of online water quality monitoring instrumentation, and considered an indicator of a water utility reaching a level of “maturity” regarding the application of online monitoring technologies. A survey conducted by Burnet et al. in 2018-2019 revealed a strong motivation of utilities to engage in testing and/or implementing microbial sensors, although several barriers to successful implementation were identified. With an ever increasing pressure on water supplies due to factors such as climate change, geo-political instability and demographic developments, collaboration between researchers, sensor developers and endusers is essential to overcome these barriers and find the best possible solutions to effectively monitor microbial water quality.
  Therefore, this interactive session aims to determine the interest and added value of establishing a Community of Practice focused on the application of online microbial sensors in the water industry, bringing together all stakeholders involved in research, development, implementation and operation of microbial sensors.
   
• Open discussion
  The event will end with an interactive session during which opinions will be shared and discussed among the audience, reflecting on the topics addressed during the day.

16.30 - End