Impact of construction and demolition waste on wetlands

Due to rapid urbanization and population growth in recent years, the global construction sector has expanded significantly, accompanied by serious environmental challenges. One of the most pressing issues is the generation of construction and demolition waste (CDW), which is heterogeneous, widespread and voluminous. This article critically examines the effects of CDW on wetland ecosystems focusing on Diepsloot and Tembisa in Johannesburg and Ekurhuleni Municipalities. Using a mixed-method approach that combines semi-structured interviews and remote sensing techniques, the study demonstrates how CDW disrupts the physical and ecological functions of wetlands. The findings confirm that CDW causes physical alteration of wetland landscapes, disrupting water flow, sedimentation patterns and natural hydrological processes essential for wetland functioning. The accumulation of CDW in wetlands results in water pollution, degrades water quality and contributes to biodiversity loss through habitat destruction and disruption of species’ breeding patterns. Furthermore, obstruction of natural drainage systems exacerbates flooding and further destabilizes these ecosystems. The article underscores the urgent need for improved waste management practices and stronger regulatory enforcement to mitigate the harmful impacts of CDW. Without meaningful reforms, continued wetland degradation threatens critical ecosystem services, including water purification, flood regulation and habitat provision.