Planting Stormwater Solutions: A methodology for siting nature-based solutions for pollution capture, habitat enhancement, and multiple health benefits

Abstract

Urban areas worldwide must manage stormwater to prevent flooding and reduce pollution. Infrastructure has historically been designed and used for the single purpose of managing stormwater, but this gray infrastructure typically has negative consequences and fails to address other challenges faced by urban areas. As an alternative, vegetated Nature-Based Solutions (NBS) such as bioretention facilities, constructed stormwater wetlands, and outfall retrofits may be used to capture and treat stormwater, while also contributing other benefits, such as reducing urban heat-island effects, increasing carbon sequestration, improving air quality, climate adaptation, and access to open space, and enhancing mental and physical health and urban biodiversity. To optimize these benefits, the siting of NBS can be crucial. We developed a spatially explicit analytical methodology, Planting Stormwater Solutions, to prioritize the siting of vegetated NBS to benefit biological diversity, social and public health, and water quality. Using Los Angeles as a case study, we demonstrate where benefits spatially converge or diverge. We found that while some of the greatest opportunities to benefit biodiversity occur along waterways, the greatest social and public health benefits may be realized for NBS installed in and around heavily developed areas. NBS sited in areas with a high density of commercial and industrial land uses may provide the greatest water quality benefits. Use of our analytical methodology may allow decision-makers with limited resources and multiple challenges to make more informed siting decisions for vegetated NBS.