Having worked with various (waste-)water utilities and seen how their operators and engineers deal with their (generally high) workload, I think it is safe to say that, for a lot of them, routine sensor maintenance is not at the top of the list of the most favourite tasks. Once sensors have been installed, they are expected to do what they are supposed to do, preferably with as little hassle as possible. When they do, maintenance is a bit of a chore, but when they don’t, it can turn into a frustrating, time-consuming nightmare. Nobody volunteers for that task.

As a result, sensors in operation do not always receive the attention they deserve. And when they are not cared for properly, the quality of the monitoring data suffers. Which results in even less motivation to look after a sensor. If it doesn’t provide reliable information anyway, why bother at all?

And this is where your best friend comes in. Friends help each other, and support you when you need them most. When it comes to keeping sensors operational and ensuring they deliver reliable and actionable data, your local water laboratory really is the best friend you can imagine. Here’s why.

Sensors and analysers can be incredibly fiddly equipment sometimes, especially the more complex types of analysers such as e.g. online biomonitors. When working on a rather complex sensor system at a water utility, I once asked a treatment engineer if he could find me a new pump. He told me he was a pump expert and could get me anything I needed. Until I told him I needed it to pump about 100 ml of liquid per hour. “That’s not a pump”, he said. Where he came from, pumps easily pumped a million times that amount. Different worlds…

Laboratory staff is used to handling such delicate equipment. They do it every day with instruments that are even more complex (and more expensive) than the average sensor or analyser. This kind of experience should not be underestimated, as it can really mean the difference between a functioning sensor and a useless piece of electronics. So, you can rest assured that your equipment will be in good hands with your friends.

Every now and then, you need to establish whether your sensors are still operating within a certain bandwidth of accuracy. A calibration procedure helps to adjust sensors showing drift, but this can be a laborious task. Water laboratories have lots of equipment themselves and are routinely skilled at performing calibrations of all sorts, so it really is no bother at all to calibrate your sensors, too. Happy to help.

The benefits of data-driven analyses include a better understanding of treatment performance and more informed decision-making for (process) optimisation. Using low-quality, unrepresentative data as input can produce bad decisions as output, following the garbage-in-garbage-out principle. Transparency regarding the quality of data is essential for generating trust and confidence in data-driven decisions, however big or small. Quality control procedures offer a wide range of tools to gain insight into the quality of monitoring data collected by sensor technologies, such as e.g. round-robin tests. Sensor systems can be tested by comparing them to an independent (e.g. laboratory) measurement to determine if the results are similar. Your friends at the water laboratory often work according to ISO 17025 standards and are thus intimately familiar with all imaginable quality control procedures for water quality testing. This means they are in an excellent position to support and implement quality control procedures which ensure the accuracy and reliability of the data collected by sensors. So that you can be sure to take the right decisions on the basis of representative data.

Keeping track of all monitoring requirements related to routine programmes and ad-hoc projects in a rapidly changing environment is not an easy task. With the introduction of risk-based monitoring schemes in the European Drinking Water Directive, establishing a fit-for-purpose and coherent water quality monitoring programme has become even more of a challenge than it used to be. Fixed lists of compliance parameters stipulated by European or national legislation are replaced by utility-specific monitoring programmes based on the outcomes of recurring risk assessments and risk management procedures. Parameters and monitoring frequencies change over time, and compliance checking is no longer limited to monitoring at the tap.

Water quality monitoring is not a matter of either laboratory analysis or sensor measurements. For each water quality challenge, it is important to find the most appropriate monitoring solution. If the dynamics are fast (seconds or minutes), sensors are preferred when available. When online sensors are not viable, e.g. for certain parameters such as pesticides or other micropollutants, laboratory data can be the analytical solution of choice.

Your friends at the water laboratory visit your utility regularly to take samples. While they are already there, they can just as easily clean and calibrate your sensors. They know their way around, and do not need supervision. This means you can focus on your own tasks, while they focus on theirs.

Well, of course, there are. Friends want you to be happy and successful, and will do whatever they can to help you achieve your goals. But yes, you will have occasional fights over matters such as who does what and why things have or haven’t been done a particular way. That’s ok. That’s what friends do. Real friends will sometimes tell each other things they do not wish to hear, but this allows both to grow and flourish. As always, communication is key. Difficulties and misunderstandings can be overcome by means of open communication. Flexibility is essential on both sides to arrive at a mutually beneficial and pleasant collaboration, based on shared goals and responsibilities.

Now, you may wonder a little whether your friends at the water laboratory are fully skilled and experienced enough to deal with all things to do with sensors. After all, they come from an analytical background, and sensor technologies could potentially form a threat to their way of life if their deployment leads to a reduction in sampling and analysis. Why would your friends involve themselves with technologies potentially damaging to their own business model? Here is where we at Sensileau come in.