#WorldWaterDay – “We cannot afford to wait”

At KWR, we have long ago adopted an approach based on scientific excellence with bridging science to practice, but not in isolation. We chose to share our knowledge also through our extensive international networks of Watershare, Global Water Research Coalition, Water Europe, Aqua Research Collaboration, to name but a few.

Water treatment

Climate change has an important influence on the availability and quality of sources of drinking water, i.e. groundwater and surface water. The quality of sources is mainly influenced by increasing salinisation, decrease and increase of river discharges in summer and winter respectively, more extreme temperatures and increased precipitation resulting in sewer overflows into surface water. Directly this will mean that the water temperature will rise, more salts and especially chloride will enter the water, the oxygen content will decrease which affects biological processes and concentrations of micropollutants will increase. The water quality will deteriorate, which will have important consequences for water treatment plants that will have to absorb this deterioration in order to continue to supply impeccable drinking water.

Water treatment plants must be able to cope with higher temperatures and higher concentrations of salts (especially chloride), organic substances and micropollutants. Different water treatment plants are used by water companies, and can be divided into different processes such as membrane filtration, oxidative, adsorption and biological processes. A very robust water treatment process is, for example, reverse osmosis, which is a membrane filtration process in which almost all substances are filtered out of the water to a high degree, including undesirable salts, organic substances and micro-pollutants. This process is perfectly capable of withstanding the challenges of climate change.

At KWR we investigate the possibilities and challenges of this process, such as

• the removal of micro-pollutions and nanoparticles,
• the use of new reverse osmosis membranes based on nanotechnology,
• the application of reverse osmosis with minimal pretreatment, en
• handling residual flows (concentrate flows) from the reverse osmosis process.

Water reuse

Enough freshwater: for all users and uses. Available groundwater sources are increasingly under pressure due to the regional coexistence of land use functions that are critical to groundwater levels or compete for available water. Groundwater resources are overexploited worldwide. Enough fresh water for all actors is also becoming an increasingly big challenge in countries like the Netherlands. In response, efforts are underway, at both regional and national levels, to achieve self-provision in freshwater and to exploit freshwater sources as efficiently as possible. This requires venturing off the beaten paths in our thinking. Moreover, instead of seeking solutions to the problem of freshwater availability independently, sectors should connect and work more with each other. We increasingly look to the use of treated residual water as an important part of the solution to improving the balance between water demand and water supply. After all, every drop that is reused, rather than being quickly discharged from an area via surface water, doesn’t need to be abstracted from the groundwater. If it is of the right quality, the residual water can be used for instance for groundwater recharge, irrigation and in industrial processes. However, responsible water reuse is key and requires an interdisciplinary approach (see illustration below).

The reuse of water is becoming an increasingly central focus of attention. Water reuse presents companies important opportunities to reduce their dependence on the available water sources.

Governance capacity

Water scarcity and reuse of treated wastewater, water pollution or adequate treatment are one of the essential challenges in meeting SDG6 clean water and sanitation for all. Beyond the technical know-how that KWR can provide, these challenges cannot be addressed by a single organisation but require different organisations that work together. As the Organisation of Economic Cooperation and Development states if we want to address the global water challenges we have to strengthen water institutions in providing cohesive, long-term and adaptive strategies for water service delivery. As such KWR has developed the Governance Capacity Analysis, which is a diagnostic tool to identify capacity-development priorities. Through a widely accredited and standardized methodology that is based on policy documents, interviews with key stakeholders and peer-feedback, we are able to pinpoint key actions. This is typically a process of joint fact-finding. As such we are able to advise cities in a specific and proactive manner. At the same time, through more than 40 assessments across the globe and our recent work in Africa, we have obtained unique empirical-based insights into the key social conditions for achieving the adequate capacity to address key water challenges. In particular, the ability to monitor, evaluate and learn across stakeholders as well as the capacity to implement existing policies is consistently observed in high performing cities.

The governance capacity of the city of Amsterdam: the bluer, the better. the main barriers that are the focus of follow-up steps and solution pathways can be seen at a glance.

The mirror of society

Sewage is not only a valuable resource for water, nutrients and energy, but also a source of information. The composition of domestic wastewater that is collected from our cities reflects our society. Domestic sewage contains residues of personal care products, pharmaceuticals, drugs of abuse and many other compounds that are used in our ‘upstairs’ society. Domestic sewage can also reflect our health, screening of antimicrobial resistance in wastewater reflects the circulation of antimicrobial resistance in people at hospitals and in homes. When the epidemic of the new coronavirus emerged in China and travelled to Europe, KWR was looking for options to contribute.  Could we support the water sector and society as a whole in some way?

KWR researchers Gertjan Medema, Leo Heijnen and Goffe Elsinga monitored the reports that came out of China and Europe and information emerged that the virus is also shed in faeces of COVID-19 patients. We had seen this before with a similar virus, during the SARS outbreak in 2003, where KWR was asked to join a WHO team to investigate the risk of spread of SARS virus via water and sanitation. SARS never reached the Netherlands, but the new SARS-Coronavirus-2 did.

So the question is: is this new virus present in sewage? And if yes, is there a risk to sewage workers? And, could we use sewage surveillance to monitor the spread of the virus in our country? We combined our knowledge on virus transmission via water systems, our methods for virus isolation and detection in water with our knowledge on sewage surveillance. In doing so we developed a method for detection of the new coronavirus in sewage. We took samples of the domestic wastewater of 7 cities and our main airport. Our goal is to see if we can detect the virus in sewage and can support the battle against this new virus with information collected from our sewage systems.

Wastewater as mirror of society: sewage surveillance of the new coronavirus?