Urban water quality

As a result of climate change, the weather is becoming drier, wetter, and warmer. This affects the quality of urban surface water. The impact differs from one area or location to the next. This knowledge dossier helps water management bodies and municipalities to gain a better picture of the potential effects of climate change and of adaptation measures on water quality. It also contains an overview of measures to combat a negative impact on water quality.

How does climate change affect ecological water quality?

Climate change affects the ecological quality of urban surface water in several ways. The water quality can change, as climate change is causing physical or chemical changes in the water itself. For example, salinisation raises the salt concentration. Climate change may also affect the concentration of oxygen, nutrients, and micro pollutants in the water. In addition, climate change affects everything living in the water, such as fish, water plants, algae, and midges.

How does climate change impact the functional water quality?

Changes in the quality of urban surface water ensuing from climate change will impact the functional uses of such surface water: the functional water quality. For example, climate change leads to an increase in the occurrence of blue-green algae, which may affect the possibilities for fishing and swimming in surface water.

How vulnerable is a water system to climate change?

Do you, in your capacity as a water management body, wish to gain insight into the vulnerability of a particular water system to climate change? This knowledge dossier comprises two helpful tools.

What renders a water system vulnerable to climate change?

Vulnerability to the effects of climate change differs from one water system to the next. Why? Every system has different characteristics, which are affected by several factors. The characteristics of a water system are categorised into six indicators. The factors affecting the indicators are referred to as “control variables”.

How do adaptation measures affect water quality?

Adaptation measures help us to climate proof the environment, in order to enable us to cope with increasing drought, precipitation, and heat. However, some adaptation measures may have a negative effect on water quality. To prevent this, it is important to be aware of the effects that may occur.

How can negative effects on water quality be counteracted?

Counteracting any negative effects of climate change or of adaptation measures on water quality may require the implementation of measures. This knowledge dossier contains a table of such “water quality measures”, along with their impact on control variables.

Knowledge dossier based on research

The background information to this knowledge dossier is found in the following research reports (in Dutch): Indicators and limiting values for urban water quality (2023), Control variables and action perspective (2022), and Impact of climate change on urban water quality (2021) The 2022 and 2023 studies were conducted by a consortium of the National Institute for Public Health and the Environment (RIVM), Royal HaskoningDHV, Deltares, Arcadis, TAUW, and Climate Adaptation Services. This consortium worked the results of these reports into an interactive knowledge document and a tool with limiting values. The 2021 study was conducted by the National Institute for Public Health and the Environment (RIVM), Deltares, Arcadis, and Wageningen Environmental Research (WENR). The studies were commissioned by the National Water and Climate Knowledge and Innovation Programme (NKWK).

Go directly to the knowledge document

Would you like to go straight to information on the impact of climate change and adaptation measures on water quality? Then view the knowledge document. This interactive guide shows how climate change and adaptation measures can affect the sensitivity of a water system.