The projected impacts of smart decline on urban runoff contamination levels

Abstract

There has been mounting interest about how the repurposing of vacant land (VL) through green infrastructure (the most common smart decline strategy) can reduce stormwater runoff and improve runoff quality, especially in legacy cities characterized by excessive industrial land uses and VL amounts. This research examines the long-term impacts of smart decline on both stormwater amounts and pollutants loads through integrating land use prediction models with green infrastructure performance models. Using the City of St. Louis, Missouri, USA as the study area, we simulate 2025 land use change using the Conversion of Land Use and its Effects (CLUE-S) and Markov Chain urban land use prediction models and assess these change’s probable impacts on urban contamination levels under different smart decline scenarios using the Long-Term Hydrologic Impact Assessment (L-THIA) performance model. The four different scenarios are: (1) a baseline scenario, (2) a 10% vacant land re-greening (VLRG) scenario, (3) a 20% VLRG scenario, and (4) a 30% VLRG scenario. The results of this study illustrate that smart decline VLRG strategies can have both direct and indirect impacts on urban stormwater runoff and their inherent contamination levels. Direct impacts on urban contamination include the reduction of stormwater runoff and non-point source (NPS) pollutants. In the 30% VLRG scenario, the annual runoff volume decreases by 11%, both physical, chemical, and bacterial pollutants are reduced by an average of 19%, compared to the baseline scenario. Indirect impacts include reduction of the possibility of illegal dumping on VL through mitigation and prevention of future vacancies.

Adapting to Climate Change: Leveraging Systems-Focused Multidisciplinary Research to Promote Resilience

“…Using a case study with different scenarios of green infrastructure, the group reported significant reductions in storm water runoff and pollutants compared with the baseline [ 122 ]. Similarly, using historical flood data and changes in green infrastructure over time, they were able to identify an optimal strategy involving protecting larger green spaces near flood prone areas to reduce the costs associated with flood damage [ 123 ].…”

Resilience of human settlements to climate change needs the convergence of urban planning and urban climate science

“…Cities create their own climate, such as the urban heat island, and have localized pollution, adding environmental stress to the atmosphere, exacerbating the warming effect seen on a regional scale. With the increasing intensity and frequency of urban flooding incidents caused by hurricanes or storms, legacy cities with many brownfields, vacant lands, and outdated infrastructure will also need to deal with growing risks of flood-related contamination (Nair et al, 2019;Zhu & Newman, 2021). The urban disaster caused by an increasing number of extreme weather episodes is an international challenge and a significant source of fatalities, property loss, social disruption and inequality.…”

Towards formulating a methodology for the integrated management of vacant areas to enable the development of Egyptian cities

“…p, 526.) (32) Some studies have demonstrated that consolidation of future vacant areas functions by modeling urban forecasting and the use of green infrastructure by re-greening vacant plots can lead to Reduced urban pollution, address natural disasters in places of floods, and also in old cities that contain large industrial land uses by incorporating land use (Zhu & Newman (2021)…”