This issue of Vitens Innoveert highlights a number of projects that have been carried out within the context of the Safe & Healthy Drinking Water theme in recent years. They are not the be-all and end-all, however, as various other interesting research projects are set to be launched in the near future. For example, the TRACER project is to be succeeded by MICROWSEQ, while ambitious follow-ups to the DOSSIER and BroNchiTis projects are also scheduled. Furthermore, a new project aimed at the development of a mobile laboratory is to follow. And last but not least, an exploratory project on customer interaction is pending.

MICROWSEQ
In the TRACER project, we investigated the possibilities of applying new measurement and monitoring techniques, such as next-generation sequencing, to detect microbial contamination. As a follow-up, we have launched the MICROWSEQ project in collaboration with Deltares. The aim of this new project is to improve the risk assessment of microbial safety of groundwater extractions. To this end, we are to further investigate the microbiological vulnerability of four groundwater extraction sites.

PatRoon
The BroNchiTis project has shown that we can detect many unknown chemical substances in water samples using techniques such as non-target screening. However, it is difficult to determine which substances these are exactly. Moreover, it is simply not feasible to identify each and every substance. The DOSSIER project studied the smart techniques available with which to select the most relevant substances. DOSSIER’s findings revealed that additional prioritisation methods are required to swiftly and efficiently determine which chemicals certainly need to be identified. Such additional methods are to be sought within the context of the ambitious PatRoon project, which is partly driven by the water sector survey carried out by the KWR Watercycle Research Institute. Attention will also be paid to software tools that could be used for the identification of unknown substances. The Vitens laboratory is to make its own in-kind contribution to the PatRoon project in the form of training.

MoDriLab
In recent years, we have carried out substantial research into the added value of online sensors for the distribution and production of drinking water. We tested various sensors that provide insight into both abnormalities in drinking water and the processes that take place during distribution. In launching the MoDriLab project, we aim to develop a mobile laboratory equipped with various sensors. The laboratory should be capable of taking online measurements, with a view to issuing a statement regarding water quality as swiftly as possible, for example in the event of a calamity.

Customer
The projects described in this magazine are primarily aimed at measuring and monitoring water quality. Besides these areas of interest, the Safe & Healthy Drinking Water theme also focuses on customer interaction. However, plans are now in place to launch a research project into the role and perception of customers in initiatives concerning sustainability and drinking water quality. This will include projects that focus on the reuse of water.

 All these scheduled projects bear witness to the fact that we intend to continue to research, develop and innovate within the context of the Safe & Healthy Drinking Water theme during the years ahead. We are keen to further improve our approach to innovation in the coming years, to ensure that new projects are even more effective. If you want to stay abreast of current projects covered by the Safe & Healthy Drinking Water theme of the Innovation & Research Agenda, please visit the theme page. 

Inspired? For further information or a partnership, please contact us through merijn.schriks@vitens.nl

 *This is an article from the magazine Vitens Innovates – Theme Safe and healthy drinking water.  

That is what hydrologist Martin de Jonge claims. The quality of Vitens’ groundwater wells is central to his work. His duties include devising monitoring strategies and analysing measurement data to identify trends. Martin has been coordinating the BroNchiTiS* research project since 2018. The project uses innovative techniques to identify any chemical substances that could potentially threaten Vitens’ groundwater wells.

“Groundwater is Vitens’ primary source for the production of drinking water,” says Martin. “The quality of this groundwater is currently so favourable, that we can use it to produce high-quality drinking water by performing just a few stages of purification. At the same time, however, we are aware that the quality is under threat. We therefore continuously monitor the water quality around our water catchment areas. We currently analyse water samples for the presence of around 800 target substances: undesirable chemical substances that we know may be present in the groundwater.”

“As part of the BroNchiTiS project, we have examined twelve sites close to extraction wells on a much broader scale. These are sites where problem substances are released from rubbish dumps, agricultural plots, urban areas, roads and polluted surface water. Non-target screening has enabled us to map the multitude of chemical substances in water samples taken there. The idea behind it is simple: if we know which substances are headed towards our wells, then we can anticipate them.”

Martin continues: “We not only took traditional water samples, but also used what are known as passive samplers for the purposes of the study. These are filters that we suspend in surface water or monitoring wells for six to twelve weeks. The majority of chemical substances attach themselves to these filters, and in high concentrations, too, as they are left in place for a considerable length of time. The number of substances that we found is literally vast. In fact, some 75,000 different substances were collected from the passive samplers. About 20,000 of these were also present in the traditional samples.”

“While the power to distinguish is quite fantastic, it also makes for a great deal of work”

“The power to distinguish is quite fantastic, of course, although it also makes for a great deal of work” After all, you don’t yet know which substances they are, and identifying them is a complicated and time-consuming process. We have nevertheless identified around 100 new substances, including various medicines. Our success in identifying these substances can be largely attributed to the fact that they are already contained in good databases. The identification of industrial pollutants is far more difficult in this respect, as many are simply not contained in open source databases.”

“Knowledge of the substances that pose a threat to our wells is vital to Vitens. Given that the basic premise is to avoid additional stages of treatment wherever possible, we first examine the option of implementing preventive measures. To this end, we largely engage in dialogue with those directly involved. Based on the substances that we find at our wells in the vicinity of landfills, we approach the competent authority to tighten the requirements for a remediation plan, for example. And if undesirable substances are found in the effluent from a wastewater treatment plant, then we contact the water board responsible.”

“The thing I like most about this project is its multidisciplinary cooperation.”

“The thing I like most about the BroNchiTiS project is its multidisciplinary cooperation.” In order to solve the research puzzle, one has to combine the professional knowledge of various experts. As a hydrologist, for example, I have to consider the best means of acquiring the appropriate water based on residence times, when it comes to taking samples from a monitoring well. The laboratory then serves as a substance detective in analysing as many substances as possible, while the data specialist applies his statistical tools to recognise patterns among the thousands of substances.”

* BroNchiTiS is a Dutch acronym for the source-oriented application of NTS techniques, which also hints that the consequences of pollutants can literally takes one’s breath away

Inspired? For further information or a partnership, please contact us through martin.dejonge@vitens.nl.

Non-target screening (NTS) potentially enables Vitens to detect thousands of unknown chemicals in water samples. It is impractical to identify all these substances, however. Vitens has therefore been carrying out joint research with Deltares and VU University Amsterdam into smart techniques with which to select the most relevant substances.

Launched in 2018, the research project is known as DOSSIER. This is a Dutch acronym for Detection of Unknown Substances in Raw Water Extracts. It concerns unknown chemical substances that Vitens detects using NTS analysis technology. The strength of this technology is its considerable power to distinguish: NTS enabled Vitens researchers to detect no fewer than 5,000 chemical substances in a single water sample. While this is valuable, it is also a huge challenge on the other hand. After all, the identification of an unknown chemical is a complicated and time-consuming process. It is therefore important to set priorities. The DOSSIER project examined possible means of doing so.

“We detected some 5,000 chemical substances in a single water sample!”

Liquid chromatography is a separation technique based on the chemical properties of substances. As part of DOSSIER, we examined the possibilities of utilising these chemical properties. During the separation process, we collected fractions of the chemical substances. We then proceeded to establish whether the chemical substances in such a fraction have an effect in what are known as bioassays.

By identifying only the chemicals from fractions that have a negative effect in the bioassays, we should (theoretically) be able to reduce the number of chemicals to be identified. By subsequently focusing on the chemicals present in higher concentrations in the same fraction, we can further reduce the number of chemicals to be identified, thus rendering the identification process more manageable.

“If a very low concentration of a chemical is present in the water, we might not detect its unique fingerprint.”

If a very low concentration of a chemical is present in a water sample, there is a chance that we might fail to detect its unique fingerprint. We have therefore also been investigating techniques that increase the concentration of chemicals in our samples. We carried out tests with three different passive samplers to this end. These are filters to which chemical substances can attach themselves. We suspended the filters in surface water, groundwater or monitoring wells for six to twelve weeks. Then we analysed them. The analysis findings showed that the concentrations of chemical substances on the filters were much higher than in traditional water samples.

Despite the availability of workable methods of prioritisation and concentration, the identification of new chemical substances is bound to remain difficult for years to come. The main reason is the lack of suitable, public libraries with databases containing the fingerprints of new chemicals. Identification is further complicated by the fact that, after use, chemicals such as pesticides form decomposition products whose fingerprints are generally unknown. Apart from this, additional prioritisation methods are required to swiftly and efficiently determine which chemicals certainly need to be identified.

Inspired? For further information or a partnership, please contact us through merijn.schriks@vitens.nl.

 *This is an article from the magazine Vitens Innovates – Theme Safe and healthy drinking water.

The timely detection of microbial contamination is an important aspect of Vitens’ duties. As part of the TRACER* project, the water company is therefore investigating whether the innovative analysis technique known as next-generation sequencing (NGS) is suitable for this purpose. An interview with Anneke Roosma, Geo Bakker and Adrie Atsma follows.

“We’ve split the project into two subprojects,” drinking water quality advisor Anneke Roosma explains. “In both cases, we are jointly investigating whether NGS might offer greater insight into biological water quality than our customary techniques, in collaboration with knowledge institute Deltares and the University of Wageningen. Furthermore, we hope the project will clarify both the opportunities that NGS offers and its limitations.”

Geo Bakker, process technology expert, adds: “NGS is a new technology that enables us to map the genetic code of microorganisms in a water sample. Until now, we used culture techniques to determine the presence of bacteria that affect drinking water quality. We filter the bacteria from a water sample, then transfer them to a specific culture medium on which only certain bacteria grow. If the bacteria eventually show up on the culture medium, then we know that this type of bacteria was also present in the water sample.”

“We hope the project will clarify both the opportunities that NGS offers and its limitations.”

Faecal bacteria
“There are a number of drawbacks to the use of culture techniques,” explains Adrie Atsma, Project Manager at the Vitens laboratory. “First of all, there are only a few bacteria that we can cultivate properly. In addition, growing a culture takes time: it is not clear whether the bacteria are present until one to two days down the line. We expect that molecular technologies will prove not only quicker, but also capable of identifying many more microorganisms in a water sample.”

Adrie vervolgt: “Binnen het eerste deelproject onderzoeken we of het mogelijk is om met NGS sporen van menselijke of dierlijke ontlasting aan te tonen. Voor het vaststellen van dit soort fecale verontreinigingen gebruiken we tot nu toe de ‘poepbacteriën’ E. coli en enterococcen als indicator. We onderzoeken nu of er alternatieven voor deze indicatoren zijn. Daarvoor brengen we met NGS in kaart welke micro-organismen in een fecaal verontreinigd watermonster zitten en welke in een schoon watermonster. Beide monsters zijn afkomstig van dezelfde locatie. We nemen een monster dat fecaal verontreinigd is en een monster nadat de betreffende leiding is gereinigd. Door de genetische codes van deze twee monsters te vergelijken kunnen we hopelijk zien welke bacteriën naast E. coli en enterococcen kenmerkend zijn voor een fecale verontreiniging en welke daarvan geschikt zijn als alternatieve indicator. Als we dat weten kunnen we voor deze indicatoren PCR-tests ontwikkelen. Daarmee kunnen we in circa vier uur een fecale verontreiniging aantonen, wat veel sneller is dan met een kweek.”

Groot onderscheidend vermogen
“The initial results show that we can detect a multitude of microorganisms using NGS,” says Anneke. “This considerable power to distinguish is a positive sign. It implies that we may ultimately be able to trace faecal contamination to a specific source in the future. For example, faecal contamination originating from cattle has a different ‘fingerprint’ to that of human faeces. At the same time, the power to distinguish poses a considerable challenge. The majority of microorganisms detected remain unidentified. The identification of all microorganisms would prove a colossal task. We therefore need to develop smart ways of establishing which organisms are of significance to us and which not.”

Surface water extraction
The second subproject involves Vitens’ use of NGS to investigate whether microbial contamination in surface water can permeate groundwater sources by means of infiltration. For the purposes of the project, the researchers are examining four so-called surface water extraction sites. Two of these, Engelse Werk and Vechterweerd, involve bank infiltration. At the remaining two, Epe and Schalterberg, Vitens infiltrates surface water during part of the year to supplement the groundwater that is extracted for the production of drinking water.

Anneke Roosma: “For this study, we take samples of the surface water, as well as from a groundwater extraction well and the drinking water that it is used to produce. We then apply NGS analysis to establish any significant difference in the microbiological composition of the three water samples. We have already analysed our first series of water samples. Analysis of the second series is currently in progress. We have already established that some of the microorganisms contained in the surface water samples are not present in the groundwater (see Figure 2). Furthermore, we have detected various types of microorganism in the drinking water that are not present in the groundwater. Our aim in carrying out this study is to gain broader insight into the microbiological reliability of the water we extract.”

Inspired? For further information or a partnership, please contact us through merijn.schriks@vitens.nl.

 *This is an article from the magazine Vitens Innovates – Safe en gezond drinkwater

This is the firm belief of both Monique Musch, Vitens’ Laboratory Manager, and Merijn Schriks, ambassador of the ‘Safe & Healthy Drinking Water’ research theme. Throughout the next few years, Vitens therefore intends to invest heavily in new measuring and analysis methods, such as next- generation sequencing (NGS) and non-target screening (NTS), in which field further research is to be carried out in keeping with Vitens’ Innovation & Research Agenda.

“In various areas, we at Vitens are privileged to be able to use clean, deep groundwater reserves for our drinking water production,” says Merijn. “This could change, however, if we are obliged to switch to alternative sources such as surface water more often in the coming years. Innovative analysis techniques are becoming increasingly important when using these kinds of sources. After all, the risk of undesirable substances being present in shallow groundwater or surface water is much greater than in deep groundwater.”

“Innovative analysis techniques are becoming increasingly important.”

Forerunner
“The great thing about the Vitens Innovation & Research Agenda is that it enables us to get acquainted and gain experience with all manner of new techniques while carrying out research projects,” explains Monique. “For example, laboratory staff who applied NGS and NTS as part of both the TRACER and BroNchiTiS projects discovered that these techniques hold a great deal of potential for Vitens. Particularly if one wishes to remain a forerunner, as we do, then one obviously needs to do a lot more than simply drawing such conclusions. You really have to start applying new techniques yourself, while also educating and training employees, and jointly discovering in practice with other parties the opportunities that these techniques offer and how you might best apply them.”

“The great thing about the Innovation & Research Agenda is that it enables us to both get acquainted and gain experience.”

Complete overview
Merijn: “NGS and NTS are both screening techniques that enable one to map all the microorganisms or chemical substances contained in a water sample. Such a complete overview of contaminants is vital, given that a water company like ours has to continually check whether we are still screening for the appropriate substances. Perfluorinated compounds are a prime example in this regard. Only recently did we become aware of the risk of these substances in the environment, thereby realising that we need to start monitoring their presence in our water samples. In concrete terms, this implies that we are going to develop a specific analysis method for perfluorinated compounds, while water samples will also be analysed as standard for their presence.”

“Only recently did we become aware of the risk of perfluorinated compounds, which prompted us to start analysing water as standard for their presence.”

“The application of NTS during the BroNchiTiS project enabled us to detect several new chemical substances in the vicinity of our groundwater wells,” Merijn continues. “These substances could eventually pose a threat to local drinking water production. We are therefore also looking into the possibilities available to remove such undesirable substances.”

Higher level

Monique: “It would be marvellous if we could incorporate such research into the Vitens Innovation & Research Agenda. This agenda is focused on the longer term, of course, and one needs to avoid the pitfall of executing all sorts of ad hoc projects. However, this does not detract from the fact that it is also important to be able to switch quickly, for example if there are clear interfaces between different themes.”

“The Innovation & Research Agenda ensures that there is a structural focus on powerful innovation.”

Merijn adds: “The Innovation & Research Agenda ensures that Vitens maintains a structural focus on powerful innovation, while reminding us to continually question whether things could actually be carried out in a smarter and more efficient manner.” This is a positive development. At the same time, I feel there is still room for improvement. Research is sometimes still fragmented. Furthermore, we do not always follow innovation processes from start to finish, partly because project staff are also very busy performing their daily duties. I therefore hope that we will succeed in raising our approach to innovation to an even higher level in the years that lie ahead.”

Inspired? For further information or a partnership, please contact us through merijn.schriks@vitens.nl of monique.musch@vitens.nl

 *This is an article from the magazine Vitens Innovates – Theme Safe and healthy drinking water