Economic growth in the nickel mining sector in Southeast Sulawesi Province, Indonesia, has accelerated development and population in Kendari City. The impact of increased immigration, transmigration, and urbanization increases the problem of deforestation to support the construction of people's homes in urban areas will result in damage to the ecosystem of the Wanggu River, Kendari City. This research uses geomorphology, demography, and ecology approaches to identify natural conditions with aerial photographs and satellite images (Google earth) simulated using ArcGis version 10.8. Then, it simulates the potential impact of flooding and pollution of the river environment due to the construction of people's houses around the riverside buffer. The study's findings reveal a discernible correlation between population growth and the heightened risk of ecological degradation within the river environment. The expansion of residential housing exerts significant stress on the river environment, resulting in the degradation of riparian areas and an increase in the river's pollution load. This deterioration in geomorphological, demographic, and ecological conditions within the river system has a direct and adverse impact on the overall health of the river ecosystem. Moreover, the results of the dynamics system simulation unequivocally indicate that river pollution is a persistent concern, with detrimental consequences extending to the mangrove area situated at the mouth of the Wanggu River, notably affecting pollution in Kendari Bay. The improvement of the built river area is useful for improving the landscape function of the river area, preventing erosion, and self-restoration of cities with rivers for ecological restoration, urban planning, and ecological management of urban landscapes in semi-arid areas with high rainfall intensity.