SuDS/BMPs/WSUD/SCMs: convergence to a blue-green infrastructure

In the original call for this special issue, we encouraged submissions on the broadest range of SuDS topics, from water quality performance to community engagement, from cost and benefits to adaptability and maintenance. The timing of the papers, from the call to final publication, has seen some change in perspective regarding SuDS, with green infrastructure and nature-based systems becoming prominent (e.g. Pauleit et al. 2019). These terms were included in the review by (Fletcher et al. 2015) and it was concluded that ‘Widespread adoption of green infrastructure is likely to drive stormwater management towards a more distributed and at-source application’ … . of how surface water is managed in the future. Recent literature is increasingly utilising the term ‘blue-green-infrastructure’ (BGI) and although SuDS (sustainable drainage systems) is still a term in use, the broader applicability of BGI is becoming apparent. In view of this, there is a need for improved integration between land use planning (including green open space planning) and water resource management (CRCWSC 2019). Increasingly the multifunctionality that BGI (including SuDS) can bring especially to urban areas is being understood and exploited.

To support the delivery of better places, with effective embedded water management, there is a continuing need to develop the science related to the design, operation and performance of SuDS. The final selection of papers presented here highlights our deepening understanding of the complex scientific processes that underpin SuDS’ design and performance, particularly with respect to water quality processes. This is valuable work that feeds into the development of modelling tools and design rules, and from this provides the quantitative evidence required to build confidence in decisions to implement SuDS in policy and practice.

Looking to the future, though, it is clear that to fully realize the potential for BGI/SuDS as multifunctional components of 21st Century cities, those responsible, not only drainage engineers, will need to adopt a broader perspective, moving beyond scientific understanding and engineering design to tackle a broad range of cross-disciplinary challenges (e.g. Bozovic et al. 2017; Bide and Coleman 2019). This, then, is the challenge for future SuDS research, both to continue with the type of robust scientific investigations presented here, and – at the same time – to join forces with planners, landscape architects and other professional dealing with urban infrastructure (energy, housing, mobility, urban agriculture, atmospheric science, biology et al.), policy makers, economists and social scientists, to address the ongoing barriers to implementation and acceptance as demonstrated by the interdisciplinarity achieved in the very successful Water Sensitive Cities initiative (CRCWSC 2019).