Monitoring and research

We continuously conduct research into water quality. This allows us to gain a thorough understanding of the ecological system in our area and take better measures in places where water quality is poor. The most important results are published in the annual monitoring report.

Water system analyses

In recent years, we have conducted extensive water system analyses. The main report, entitled ' ' (Hollands Noorderkwartier Water System Analysis), provides more information about the various components, such as history, land use, the water system, and ecology. Hollands Noorderkwartier is divided into 51 areas, all of which are described in seven sub-reports: Boezemwateren, Polders Texel, Wieringerland, West-Friesland, Kennemerland, Laag-Holland and the Duingebieden. These reports also discuss the current water quality, bottlenecks and possible measures for each area.

Water quality monitoring

The current water quality is determined on the basis of measurements that we carry out every year. For the Water Framework Directive (WFD), we monitor ecological and chemical targets throughout our management area. For the ecological targets, we check the water for the presence of algae, aquatic plants, small aquatic animals, and fish. We also look at other characteristics of the water, such as phosphate and nitrogen content, oxygen concentration, salinity, acidity, and transparency. The chemical WFD objectives relate to 45 hazardous and toxic substances (priority substances) and 77 so-called 'specific pollutants'. During monitoring, we investigate whether these substances are present in surface water and, if so, whether they comply with the legal standard.

In addition, there is separate monitoring of crop protection products at locations in the neighbourhood various types of crops, such as bulbs and arable farming, but also in urban and nature areas. This monitoring is for our own insights and enforcement, but also partly for the National Monitoring Network for Crop Protection Products and the Pesticide Atlas.

All data we collect for both types of monitoring can be found on the Aquadesk website , which is accessible to everyone after free registration.

Swimming water

Together with the Waterproef Foundation laboratory, we ensure that the 31 official swimming locations in our waters are sampled monthly for swimming water parameters. These includeblue-green algae, which can be toxic, and various bacteria, including E. coli. We also measure transparency, temperature, pH, etc. All these factors influence the quality of the swimming water.

The official swimming locations can be recognized by large blue signs at the outdoor swimming area and can also be found on the website www.zwemwater.nl. Here, measurements are recorded and the results of the measurements are published. For more information, see the Swimming Water page.

Monitoring nature-friendly banks

By the end of 2027, all surface water in the Netherlands must comply with the objectives of the WFD. The construction of nature-friendly banks (NFBs) is one of the measures we use as water managers to improve water quality. The question now is: how much does the construction of NVO contribute to achieving these objectives? In order to monitor the effects on aquatic animals (macrofauna) and plants (macrophytes), the NVO monitoring network was set up in 2014, comprising 40 NVO spread across our management area.

Compared to the baseline measurement, the latest measurement year at the same location paints a very positive picture. At more than 90% of the NWOs, the number of plant species and the number of aquatic animals (macrofauna taxa) found has increased. Even though not all NWOs meet the water quality objectives of the WFD, the construction of NWOs does contribute to a higher score at most locations. So far, the construction of the NVOs has had a greater effect on the increase in the number of species than on the WFD score. Monitoring shows that the construction of NVOs contributes positively to biodiversity in any case (see article or detailed report).

Urban water ecosystem assessments

In addition to regular monitoring, we conduct an annual Ecoscan urban water assessment in one or more municipalities. This involves examining and assessing all water within the built-up area and all primary waterways outside the built-up area in terms of Ecology, Banks, Ecology, Water, and Experience. An Ecoscan is an assessment of waterways using Stowa's ecological assessment system for urban waters. We make a vegetation survey for each waterway and note the degree of coverage, vegetation structure, and morphological and hydrological characteristics. Each route is assessed on a five-point scale, from good to poor, for the characteristics of Experience, Ecology Bank, and Ecology Water. If you would like to know more about Ecoscans for urban water, please contact us.

Research

Knowledge is of great importance to a regional water manager. In today's rapidly changing world, despite the widespread and easy dissemination of knowledge, it is still very important to have the right and up-to-date knowledge at your disposal, to be able to understand it and apply it. That is why we have been committed to applied research for many years. In the field of water quality, this relates, for example, to new measurement techniques (see below), greenhouse gas emissions, passive sampling, and impact analysis of, for example, aquathermal energy. The arrival of (invasive) exotic species and a good approach for when these species cause problems are also closely monitored; see, for example, the page on crayfish. 

eDNA

We monitor surface waters to gain insight into the ecological status of a water body and to identify areas for improvement. In recent years, several promising new monitoring methods using environmental DNA (eDNA) have been developed. We are closely following these new developments and are involved in various pilot projects and research projects, such as TKI DNA Diatom Biosensor and eDNA food web analyses for system understanding and status assessment.

Aquathermal energy

Water authorities can contribute to the energy transition by making surface water and wastewater available for heat extraction. This involves the use of proven techniques such as heat exchangers, heat transport, and thermal energy storage (TES). A relatively new development is the link with the water systems managed by water authorities. This creates a need for new frameworks and preconditions within which extraction can take place. Research is being conducted in partnerships into the effects of heat extraction from different types of water. The effect of temperature changes on ecological factors plays a particularly important role in this. In the case of smaller waterways, the necessary flow may also impose preconditions on the possibilities for extraction. The research should lead to clear frameworks for the application of aquathermal energy. For more information, see the Aquathermal Energy page.