Sustainable Flood Risk and Stormwater Management in Blue‐Green Cities; an Interdisciplinary Case Study in Portland, Oregon

Emily C. O’Donnell,Faith Ka Shun Chan,Colin R. Thorne,J. Alan Yeakley

doi:10.1111/1752-1688.12854

Abstract

AbstractBlue‐Green Infrastructure (BGI) is recognized as a viable strategy to manage stormwater and flood risk, and its multifunctionality may further enrich society through the provision of multiple cobenefits that extend far beyond the hydrosphere. Portland, Oregon, is an internationally renowned leader in the implementation of BGI and showcases many best practice examples. Nonetheless, a range of interdisciplinary barriers and uncertainties continue to cloud decision making and impede wider implementation of BGI. In this paper, we synthesize research conducted by the “Clean Water for All” (CWfA) research project and demonstrate that interdisciplinary evaluation of the benefits of Portland’s BGI, focusing on green street bioswales and the East Lents Floodplain Restoration Project, is essential to address biophysical and sociopolitical barriers. Effective interdisciplinary approaches require sustained interaction and collaboration to integrate disciplinary expertise toward a common problem‐solving purpose, and strong leadership from researchers adapt at spanning disciplinary boundaries. While the disciplinary differences in methodologies were embraced in the CWfA project, and pivotal to providing evidence of the disparate benefits of multifunctional BGI, cross‐disciplinary engagement, knowledge coproduction, and data exchanges during the research process were of paramount importance to reduce the potential for fragmentation and ensure research remained integrated.

Highlights

Municipalities across the United States (U.S.) are increasingly using Green Infrastructure (GI) as a cost-effective measure to manage stormwater and improve water quality (McPhillips and Matsler 2018; Shandas et al 2020)
Designing and delivering effective flood risk and stormwater management strategies is more than a purely engineering challenge; addressing the scientific aspects in isolation can rarely achieve the desired societal results owing to the complexity of interactions between natural and societal components of stormwater management (Morss et al 2005)
Blue-Green Infrastructure (BGI) is recognized as a viable strategy to manage stormwater and flood risk, and its multifunctionality may further enrich society through the provision of multiple cobenefits that extend beyond the hydrosphere, including urban regeneration, climate change adaptation, recreation and public amenity, health and well-being, open space improvements, and enhanced biodiversity

Summary

INTRODUCTION

Municipalities across the United States (U.S.) are increasingly using Green Infrastructure (GI) as a cost-effective measure to manage stormwater and improve water quality (McPhillips and Matsler 2018; Shandas et al 2020). This, in line with findings reported under Theme 2 regarding the minimal maintenance required to maintain functionality of the East Lents floodplain, suggests that BGI assets in Portland have the potential to effectively manage stormwater and improve water quality, without significant investment in complex maintenance regimes This negates some of the sociopolitical uncertainty surrounding costs of maintaining BGI (identified under Theme 1). Less visible, cobenefits, such as carbon sequestration (as part of climate change adaptation objectives), air quality improvement, and noise reduction, are less widely understood, suggesting that the multifunctionality of BGI is not routinely acknowledged This may be due to challenges in identifying and quantifying the range of BGI benefits that extend beyond water and flood risk management, which requires an interdisciplinary team to fully address. There are limitation to this approach and uncertainties associated with the scale of analysis

Limitations

Findings

CONCLUSIONS