Optimizing nature-based solutions by combining social equity,
hydro-environmental efficiency, and economic costs through a novel Gini
coefficient
Abstract
A robust multi-functional decision support system for widespread
planning of nature-based solutions (NBSs) must incorporate components of
social equity. NBS systems advance social well-being through enhanced
levels of greenspace, which have been shown to improve physical health
(e.g., heart disease, diabetes), mental health (e.g., post-traumatic
stress disorder, depression), and socio-economics (e.g., property
values, aesthetics, recreation). However, current optimization
frameworks for NBSs rely on stormwater quantity abatement and, to a
lesser extent, economic costs and environmental pollutant mitigation.
Therefore, the objective of this study is to explore how strategic
management strategies associated with NBS planning may be improved,
while considering the tripartite interactions between hydrological,
environmental, and societal conditions. Here, a large-scale NBS
watershed was calibrated to local conditions using standard
hydro-environmental modeling (i.e., EPA’s SWMM) and optimized on the
basis of stormwater abatement, pollutant load reduction, and economic
efficiency. The spatial allocation of possible NBS features was
integrated with properties of social equity through a novel framework
involving the Area Deprivation Index (ADI) and a composite Gini
coefficient. By embedding social equity into the fabric of the NBS
planning process, we provide an opportunity for improving social justice
and spurring further community buy-in toward a balanced system. This
study demonstrates how the optimal spatial placement of NBSs is
location-dependent according to both the physical and human properties
of the watershed.