Urban stormwater retention capacity of nature-based solutions at different climatic conditions

• Published in: Nature-based solutions 2022-12, Vol.2, p.100038, Article 100038
• Main Authors: Kõiv-Vainik, Margit, Kill, Keit, Espenberg, Mikk, Uuemaa, Evelyn, Teemusk, Alar, Maddison, Martin, Palta, Monica M., Török, Liliana, Mander, Ülo, Scholz, Miklas, Kasak, Kuno
• Format: Article
• Language: English
• Subjects: Bioretention system; Constructed wetland; Filter strip; Green infrastructure; Green roof; Permeable pavement; Vegetated swale
• ISSN: 2772-4115; 2772-4115
• DOI: 10.1016/j.nbsj.2022.100038

•Nature-based solutions for stormwater management help to adapt to climate change and reduce water pollution and flooding risks, lower high cost of damage control and prevent risks on human health and wellbeing.•Despite a vast amount of data available from application and research, there is a lack of decisive information on stormwater retention capacity of nature-based solutions created for sustainable stormwater management. The available data show large variability in performance across climatic conditions. It is therefore hard to set widely applicable guidelines for NBS implementation.•The further development of NBSs to support urban stormwater retention should be informed by and developed concurrently with the adaptation strategies to cope with climate change, especially with increasing frequency of extreme precipitation events that lead to high volumes of stormwater runoff. Climate change and the continuing increase in human population creates a growing need to tackle urban stormwater problems. One promising mitigation option is by using nature-based solutions (NBS) – especially sustainable urban stormwater management technologies that are key elements of NBS action. We used a synthesis approach to compile available information about urban stormwater retention capacity of the most common sustainable urban drainage systems (SUDS) in different climatic conditions. Those SUDS targeting stormwater management through water retention and removal solutions (mainly by infiltration, overland flow and evapotranspiration), were addressed in this study. Selected SUDS were green roofs, bioretention systems (i.e. rain gardens), buffer and filter strips, vegetated swales, constructed wetlands, and water-pervious pavements. We found that despite a vast amount of data available from real-life applications and research results, there is a lack of decisive information about stormwater retention and removal capacity of selected SUDS. The available data show large variability in performance across different climatic conditions. It is therefore a challenge to set conclusive widely applicable guidelines for SUDS implementation based on available water retention data. Adequate data were available only to evaluate the water retention capacity of green roofs (average 56±20%) and we provide a comprehensive review on this function. However, as with other SUDS, still the same problem of high variability in the performance (min 11% and max 99% of retention) remains. This limits our