Assessing the effectiveness of green infrastructure in urban areas - for mitigation of climate change-induced extreme events in South Africa: a case study of the Johannesburg CBD

Abstract

The rationale of this research study is to examine the effectiveness of green infrastructure in urban areas for mitigation of climate change, with specific interest in this case study being the Johannesburg Central Business District. The study asserts that green infrastructure should be implemented as a measure to mitigate the effects of the urban heat island effect and urban flooding. The study formulates evidence from municipal authorities, private sector specialists, and local community members to understand the local context and institutional processes influencing the adoption of green infrastructure. The study reveals that the urban heat island effect and flood risk are crucial threats to Johannesburg’s urban environment, and that there are vulnerable populations that are disproportionately affected. Through assessing the effectiveness of green infrastructure, such as green vegetation-covered roofs, bioswales, wetlands, permeable pavements, and urban trees, the study demonstrates green infrastructure’s ability to provide holistic benefits spanning from urban temperature regulation to stormwater management, to social equity improvement. Furthermore, the study presents notable barriers such as institutional silos, fiscal constraints, and regulatory gaps to the adoption of green infrastructure in the city of Johannesburg. The study concludes with recommendations for integrated policy strategies, clear custodianship, and community engagement in the development of a climate-resilient urban environment in Johannesburg, thus informing future research and broader discussions on urban resilience and climate adaptation in the Global South.