Can We Really Have It All?—Designing Multifunctionality with Sustainable Urban Drainage System Elements

Abstract

Multifunctionality is seen as one of the key benefits delivered by sustainable urban drainage systems (SUDS). It has been promoted by both scientific research and practical guidelines. However, interrelations between different benefits are vaguely defined, thus highlighting a lack of knowledge on ways they could be promoted in the actual design process. In this research, multifunctionality has been studied with the help of scenario analysis. Three stormwater scenarios involving different range of SUDS elements have been designed for the case area of Kirstinpuisto in the city of Turku, Finland. Thereafter, the alternative design scenarios have been assessed with four criteria related to multifunctionality (water quantity, water quality, amenity, and biodiversity). The results showed that multifunctionality could be analyzed in the design phase itself, and thus provided knowingly. However, assessing amenity and biodiversity values is more complex and in addition, we still lack proper methods. As the four criteria have mutual interconnections, multifunctionality should be considered during the landscape architectural design, or else we could likely lose some benefits related to multifunctionality. This reinforces emerging understanding that an interdisciplinary approach is needed to combine ecological comprehension together with the system thinking into SUDS design, locating them not as individual elements or as a part of the treatment train, but in connection with wider social ecological framework of urban landscape.

It Is Not Easy Being Green: Recognizing Unintended Consequences of Green Stormwater Infrastructure

“…The actual functions of GSI (whether physical, chemical, biological, or social) are more significant than the mere perception of having installed GSI, and therefore steps must be taken to ensure that the actual functions are the desired functions. Not only that, but all of these functions are fundamentally interconnected and must be considered simultaneously in order to effectively meet goals [27].…”

“…Similarly, there is an emerging body of research on the shortcomings and limitations of GSI [24][25][26][27], and we now know that "green" is not the same as "infallible." For example, rain gardens have become a common, if not popular, GSI methodology used in many stormwater management plans.…”

Community Involvement in the Implementation of Sustainable Urban Drainage Systems (SUDSs): The Case of Bon Pastor, Barcelona

“…Interestingly, the term used to refer to SUDSs by managers and government actors was "SUDS" (interviews #1, #2, #3, and #4), but in the interviews with the AVV and the community, these two referred to SUDS as the "landscaping/gardening project" (interviews #5, #6, #7, #8, #9, and #10). As stated previously by Lähde, Khadka, Tahvonen, and Kokkonen [29], the multifunctionality of SUDSs is frequently reduced to the benefits it brings as urban green space. Both the AVV and community directly intervened in the design of parks and sidewalks, and therefore perceived it as a holistic urban design that provided extra benefits.…”

“…As highlighted in the previous section, the main objective of flood risk management used to be to keep water out of the city, so that it caused the minimum harm possible. In contrast with conventional drainage prioritizing quantity over water quality, SUDSs aim to create multi-functional systems, achieving an equal balance of water quantity, water quality, and biodiversity [9,24,27,29,30]. These three areas take into account the effects of climate change against which new resource management actions and climate mitigation and adaptation actions need to be developed.…”

“…The main benefits of applying these systems are twofold. First, they provide quality and quantity control of runoff water and, second, they offer other environmental and positive impacts [12,29,30,32]. However, since SUDS convey a more holistic and sustainable way of managing stormwater, their benefits extend not only to hydrological, environmental, and social aspects but also to landscape, urban, and economic issues [11,12,32].…”