Green stormwater infrastructure (GSI) measures provide a wide range of benefits beyond simply dealing with stormwater. In the United Kingdom such measures are termed sustainable drainage systems (SuDS). There are a number of tools and procedures for assessing the benefits provided, some of which give a monetized bottom line. A U.K. project led by the Construction Industry Research and Information Association (CIRIA) has reviewed the available knowledge and techniques for valuing GSI and other benefits, and from this developed a new freely available valuation tool, known as the Benefits of SuDS Tool (BeST). This has been further developed to include spatial and temporal planning for the incremental implementation of a portfolio of SuDS over time and in extent. The tool is now being used in various countries for scenario planning to assist decision makers to explore future options and their relative robustness and flexibility over time. Case studies are presented from the United Kingdom and the Netherlands to illustrate the use of the tool and methods developed.

Urban water systems face severe challenges such as urbanisation, population growth and climate change. Traditional technical solutions, i.e., pipe-based, grey infrastructure, have a single purpose and are proven to be unsustainable compared to multi-purpose nature-based solutions. Green Infrastructure encompasses on-site stormwater management practices, which, in contrast to the centralised grey infrastructure, are often decentralised. Technologies such as green roofs, walls, trees, infiltration trenches, wetlands, rainwater harvesting and permeable pavements exhibit multi-functionality. They are capable of reducing stormwater runoff, retaining stormwater in the landscape, preserving the natural water balance, enhancing local climate resilience and also delivering ecological, social and community services. Creating multi-functional, multiple-benefit systems, however, also warrants multidisciplinary approaches involving landscape architects, urban planners, engineers and more to successfully create a balance between cities and nature. This Special Issue aims to bridge this multidisciplinary research gap by collecting recent challenges and opportunities from on-site systems up to the watershed scale.

Water-Sensitive Urban Design (WSUD) offers an approach for alternative spatial organisation of cities and infrastructures fit to address urban and climatic challenges. However, its relevance in all contexts is questioned and transferability concerns arise when mainstreamed. Instead of considering water sensitivity as guiding concept for the ultimate state of an urban environment, this article argues that water sensitivity is a context- and culture-specific variable, dictated and confined by other site variables. As such, WSUD implies an interaction between water sensitivity as context and concept, in which context shapes concept and concept provides focus on how to address context. Sensitivity therefore refers to the thoughtfulness of reading a context, highlighting to what extent site-specific urban conditions can be identified to be considered water-sensitive. This understanding enables local urban designers and water managers to appropriate and engage in WSUD fit for the cultural, socio-economic, and physical context.

In rapidly growing urban contexts, water plays a pivotal role in the transitions the urban environment goes through to sustain the quality of life of its population. Spatial planning and design are essential for the facilitation and manifestation of such transitions. Focusing on Bhuj, a rapidly growing Indian city in a hot arid desert climate, its crucial yet changing sensitivity to urban water flows over time is assessed. The concept of water sensitivity is coined as a goal to pursue by the Water-Sensitive Urban Design approach. In India, however, much of the urban design and development processes are of an unplanned and informal nature, seemingly inhibiting the water sensitivity of urban transitions. Reviewing spatial planning paradigms and their manifestation in space in Bhuj over time, however, brings to light a pre-existing water sensitivity. Yet it also shows a shift from the supply security-oriented ingenious watershed expansion to catastrophe-steered and urban expansion-driven water system negligence. Review and discussion of past and present urban water transitions and management points out drivers, barriers, and their interrelationships, to enable and advance water-sensitive urban development tied to local history, traditional knowledge, and context specificities.