Towards symbiotic urbanism : mitigating the impact of river channelization in the New Territories of Hong Kong

Contemporary urbanization is often characterized by the spatial intertwining of urban and rural functions. Rapid urbanization typically results in transforming peri-urban landscapes from primarily rural to urban-oriented. In this process, channelization has been commonly adopted to control flooding in planned urban development. However, as a stand-alone engineering-driven solution, channelization disrupts the natural equilibrium of the watershed. Notably, this urban-oriented physical transformation of hydrologic systems can aggravate structural changes in ecological regimes, affecting the environmental conditions of the surrounding land and accelerating landscape transformations. Furthermore, it can lead to deleterious societal implications in heavily inhabited areas. Differently, mitigation strategies may produce a socio-spatial response to the progressive deterioration of rural landscapes. Nevertheless, this topic is still addressed by a paucity of research. This study analyzes the impacts of environmental mitigation strategies in channelization on landscape transformation using the case of the Sheung Yue River in the New Territories of Hong Kong. Longitudinal data on the morphological change of the Sheung Yue River and the landscape pattern modifications at the catchment level from 1994 to 2022 interpreted from aerial photographs and high-resolution satellite imagery were analyzed, controlling for external factors. Additionally, in-depth interviews provided crucial knowledge on the societal response to the landscape mutation. The results indicate that integrating environmental mitigation strategies in channelization can reduce the negative impacts of the engineering-driven transformation of the hydrologic systems. The findings highlight the significance of socio-environmental responsive urban development strategies of urban infrastructure mitigation for policy-making in Southeast Asia. The research also discusses the close interconnection of environmental and social factors in urbanization, revealing the potential to consolidate a dynamic equilibrium of hydrologic systems and human habitats for sustainable urban development.