| dc.description.abstract | Increasing pressure from anthropogenic sources in combination with more sensitive measurement techniques has led to an increase in the number of emerging contaminants detected in surface or drinking water. Emerging contaminants are chemical substances or pathogenic microorganisms that pose a new threat to public health through the exposure to drinking water. Since it is practically impossible to monitor all emerging contaminants, prioritization methods help to make a well-founded choice which contaminants require the most attention.
This study examined the added value of integrating climate change criteria in a prioritization method for emerging risks to drinking water quality, since there is scientific consensus that climate change has a negative effect on the quality of surface water and therefore also on drinking water quality. To formulate the climate change criteria, the Multi-Criteria Decision Analysis (MCDA) technique provided an assessment framework to combine objective technical information with subjective interpretations of experts. The MCDA framework aims to minimize the chance of bias by following a transparent and systematic approach.
A literature review on worldwide scientific literature in combination with a Dutch climate scenario showed the most dominant effects of climate change on surface water quality in the Netherlands. Thereafter, a final set of seven criteria was drawn up in consultation with drinking water experts. These criteria are related to three climate variables, namely air temperature, precipitation and drought.
A selection of fifteen chemical and twelve microbial contaminants was ranked using the formulated criteria. Evaluation of this ranking suggested an increased exposure potential of certain contaminants due to climate change, and also that not all contaminants are affected to the same extent. Mainly pathogens that are able to grow in nutrient-poor conditions with high water temperatures and contaminants that are able to be transported to the river system by runoff, resuspension or combined sewer overflow become more important. The results implicated that the integration of climate change in a prioritization method for emerging risks to Dutch drinking water quality does have added value. The integration can support futureproof policy and promote proactive identification of emerging contaminants of potential high concern. | |
