Ecohydrology

Source protection and groundwater management

An effective and reliable drinking water provision requires that sufficient groundwater of constantly good quality be available. However, the quality of groundwater and surface water is under growing pressure. Currently, nitrate, pesticides, old soil pollution and emerging contaminants already present bottlenecks for many groundwater abstraction operations. Groundwater monitoring networks indicate that these bottlenecks persist for the time being. The steady development of (new) emerging contaminants, climate change and demographic growth raise added concerns about the future of groundwater quality. Moreover, the increased demand for space for the energy transition and climate adaptation threatens to deplete alternative production sites. Groundwater protection offers various tools and solutions to prevent undesirable influences on groundwater quality, and to make function combinations possible with drinking water. KWR conducts policy-support research to substantively underpin groundwater protection and to address bottlenecks. We also develop modern protection methods that rely on the synergy of functions (such as nature, water conservation and low-emission agriculture), or new forms of risk management that are based for example on intervention rather than prevention. Lastly, we also develop practically implementable risk assessment methods, such as REFLECT and TRANSATOMIC and various tracer techniques.

Arnaut van Loon Expert Source protection and groundwater management

Freshwater Resources Management

The long term freshwater provision is under pressure. Besides the flooding caused by heavy rainfall, our country is also increasingly confronted with drought damage to agriculture and nature. Furthermore, pressure on the supplies of water for other applications, such as the production of drinking water, is growing. In response to these problems, KWR works on developing knowledge and solutions to safeguard the future freshwater provision, soil and (ground)water quality, and nature (biodiversity). We carry out research on (ground)water management in which different sources of water (precipitation, surface water, groundwater, but also alternative sources, such as treated residual water) are used efficiently and responsibly, and groundwater is actively replenished. An example of a programme in which we pursue these objectives is WiCE  – Zuinig met Zoet, which configures circular, adaptive and cross-sectoral measures for a robust freshwater provision. Within the Lumbricus knowledge and research programme, we collaborate intensively with twenty partners on a climate-robust soil and water system on the high sandy ground regions in the East and South of the Netherlands. Concretely, this involves the development of innovative drainage/infiltration systems aimed at both maximising water retention and actively recharging the groundwater, constantly anticipating future climate developments. We also work in pilots on the reuse of treated residual water for the provision of freshwater. By not discharging residual water unused, and applying it instead in fighting drought, we can mitigate water shortages. This research brings together a variety of disciplines within KWR to jointly quantify the opportunities and risks involved in the reuse of effluent. An application example is provided by the Bavaria Brewery which, working with farmers and water managers, makes use of its treated residual water (effluent) to lessen water shortages in agriculture. In addition, together with the Water Factory, we explore the possibilities of using extensively treated residual water in other sectors, with the aim of decreasingthe pressure on groundwater sources.

Ruud Bartholomeus Expert Freshwater Resources Management

Ecological management and restoration

Nature and biodiversity are under considerable pressure because of intensive land use, large-scale pollution and climate change.  In order to take targeted actions in nature management, restoration and development, a good understanding is required of the interaction between water management, hydrochemistry and geochemistry, and of the functioning of ecosystems. This is why KWR develops knowledge about effective management and restoration measures in a wide range of ecosystems. We do this on the basis of empirical research, monitoring and modelling, working in close collaboration with management practice. We examine the impact of water management interventions, changes in water quality and local management measures. Using hydro-ecological system analysis, we solve complex questions about the functioning of nature areas and about the restoration possibilities and function combinations with other forms of land use. We also study the impact of climate change and atmospheric nitrogen deposition in ecosystems. Furthermore, we analyse the effectiveness of measures taken in nature areas to reduce the negative ecosystem impacts of high nitrogen deposition.

Camiel Aggenbach Expert Ecological management and restoration

Urban Ecohydrology

Both flooding and heat stress present a growing problem in urban environments worldwide. Rainfall is becoming more frequent and heavier, while the increased compaction of urban areas leads to a reduction of water-infiltrating surfaces. The result is more surface discharge of the water and over-burdened rainwater and/or surface water discharge systems. Climate change increases the probability of heat waves and of accompanying heat stress, generating harmful consequences for public health and labour productivity, as well as increased energy consumption for cooling. At the same time, the rapid discharge during dry periods means that there is little water available for evaporation in urban green spaces, and that groundwater levels can drop significantly. This has potentially negative consequences for buildings and infrastructure. KWR offers solutions to these problems through research into urban green spaces. This involves a focus on planning cities differently, with a focus on capturing and retaining precipitation surpluses, and making this water later available during periods of shortage. But space in cities is scarce. This means that tailored approaches are called for, in which smart water technology is combined with urban green spaces and, where possible, efficient use is made of the subsurface. One example are the innovative blue-green roofs like those in the  Smartroof 2.0 project, in which roofs are being developed that provide optimal evaporation – and thus cooling. Another application involves the innovative sports pitches in the CitySports project, for which artificial grass has been developed that can retain water, making it available for evaporation. Our research also explores the possible use of green zones for the pre-treatment of stormwater runoff before its infiltration. Deeper aquifers can be used in this context for the infiltration, storage and extraction of stormwater, thereby reducing flooding and improving the water provision in the city.

Gijsbert Cirkel Expert Urban Ecohydrology