Failure modes across the life cycle of nature-based stormwater solutions: a systematic review of planning, design, and maintenance challenges

ABSTRACT Nature-based solutions (NBSs) are often considered to be cure-all remedies for mitigating risks arising from climate change, among others. This study explores the failure modes of NBSs in stormwater management, and analyses challenges across the different stages of their life cycles, including planning, design, and operation. The PRISMA methodology was applied to carry out a systematic literature review to identify the main triggers, consequences and potential mitigation measures for different failure modes and challenges, with a view to enhancing the long-term performance of NBSs. Each identified failure mode was classified along the three typological dimensions of severity, origin and preventability, with sub-dimensions for qualitative and quantitative analysis. Based on 76 reviewed studies, it was concluded that preventable and intrinsic failures dominate the early stages (planning and design), whereas induced and extrinsic failures tend to manifest during operation and maintenance. The application of interdisciplinary and catchment-scale thinking in planning reduces the probability and severity of failure in the design and operation stages. Standardised and data-based approaches are needed to mitigate NBS failures throughout the life cycle.