Sustainable urban drainage systems (SuDS) or nature-based solutions (NBSs) are widely implemented to collect, store and infiltrate stormwater. The buildup of pollutants is expected in NBSs, and Dutch guidelines advise monitoring the topsoil of bio-swales every 5 years. In the Netherlands, almost every municipality has implemented bio-swales. Some municipalities have over 300 bio-swales, and monitoring all their NBSs is challenging due to cost and capacity. In this study, 20 locations where bio-swales with ages ranging between 10 and 20 years old were selected for a field investigation to answer the following question: is the soil quality of bio-swales after 10 years still acceptable? Portable XRF instruments were used to detect potential toxic elements (PTEs) for in situ measurements. The results showed that for copper (Cu), zinc (Zn) and lead (Pb), 30%, 40% and 25% of the locations show values above the threshold and 5%, 20% and 0% above the intervention threshold, meaning immediate action should be taken. The results are of importance for stakeholders in (inter)national cities that implement, maintain, and monitor NBS. Knowledge of stormwater and soil quality related to long-term health risks from NBS enables urban planners to implement the mostappropriate stormwater management strategies. With these research results, the Dutch guidelines for design, construction, and maintenance can be updated, and stakeholders are reminded that the monitoring of green infrastructure should be planned and executed every 5 years.
In dit boekje vindt u leuke tips, mogelijkheden en tricks om te bewegen. Er staan verschillende oefeningen en trainingen in. Ook vindt u hierin een instructie voor video-bellen om in contact te kunnen blijven met uw dierbaren.Dit boekje is ontwikkeld in samenwerking met studenten van de Minor Designing User Research in het kader van de studie en behoefte-onderzoek voor BAAT. Dit project is gesponsord vanuit Zaaigeld Urban Vitality (Hogeschool van Amsterdam)
As the field of climate adaptation has entered an implementation and acceleration phase, measures for urban water and heat management are rapidly spreading in cities across the globe. Especially nature-based solutions have seen a recent rise in implementation to fight flooding, heat, drought, and biodiversity loss. Despite decades of experience, there is still a lot unknown about the long-term functioning of these measures and how this relates to design, development, and maintenance decisions. To this end, this chapter explores the relations between characteristics and performances of urban nature-based solutions, based on empirical research conducted in over 50 swales throughout the Netherlands between 2021 and 2022. The research combined various fieldwork methods such as full-scale infiltration tests to assess the hydraulic functionality and heavy metal accumulation tests by using an XRF-scanner, as well as neighborhood surveys to assess local perceptions of these swales and their functions. This chapter describes and illustrates these approaches for mapping and assessing the performance of swales, followed by a reflection on their suitability for linking design choices and performance indicators. Based on national guidelines, these indicators help to establish minimal performance quotas to evaluate and compare the performance of swales. While most of the researched swales met national criteria for hydraulic performance, almost a third of investigated swales exceeded norms for heavy metal accumulation. By building up a national database of swales and data derived through measurements, we attempt to find patterns among successes and failures in swale design through cross-case comparison, but conclude that these heavily rely on local circumstances and context-depending design choices. Expanding on mapping, assessment, and evaluation approaches can lead to a better understanding of these context-depending chances and risks for developing nature-based solutions.
