Regenerating Sponge City to Sponge Watershed through an Innovative Framework for Urban Water Resilience

In recent years, cities universal are advocating 'resilience' in terms of water-related challenges. Accompanied by the development of sponge city construction, several emerging stormwater management practices are prevailing worldwide. This paper proposes a regenerative argument for sponge city construction from the urban scale towards the watershed scale by strengthening the urban water resilience and sustainability. An innovative framework is established to address urban water issues and human livability via 20 conventional and advanced indicators and the interrelations between the modules of water resilience, water resource, water treatment, water ecology, waterscape, and water management. Six representative cities from the sponge city construction pilot in South China have been selected, and the compatibility and divergence between their guidelines and the sponge watershed framework are revealed through pair analyses and parameter calculation. The diverse perspectives behind the scores have been discussed carefully, and the successful experiences of excellent cities are systematically summarized and promoted. The analyses and findings in this research have significant methodological implications for shifting the sponge city practice towards linking urban development with watershed ecological conservation. The proposed framework and strategies provide a reference for an integrated solution of watershed health and wellbeing in the next generation sponge city practice.