Collaborative governance in urban water area conservation: Strategies for mitigating blue space encroachment

Guangzhou City, Guangdong Province, China. The degradation of urban blue spaces threatens hydrological sustainability. This study investigates how collaborative governance can mitigate blue space encroachment during urban development. We establish an evolutionary game model between local governments and development companies, incorporating public participation as a key external factor. Our analysis reveals four stable equilibrium points governing the region's urban blue spaces. A sustainable equilibrium emerges under specific conditions, where developers adopt reasonable strategies and governments implement positive development and protection measures. We use numerical simulations, grounded in a case study of Guangzhou, to examine how development company decision-making, local government policy interventions, and the intensity of government regulation and public oversight collectively influence the evolutionary game dynamics. Development company behavior is significantly driven by a cost-benefit analysis, while local government behavior is influenced by factors such as political gains, regulatory costs, reputational damage, and administrative accountability. Stronger government regulation and increased public oversight incentivize governments to adopt positive environmental protection strategies, which, in turn, increases the likelihood of reasonable development by development companies. This research introduces the evolutionary game model to the field of blue space development and regulation. Furthermore, it provides the region's policymakers with a theoretical framework for crafting effective blue space policies that can guide urban development towards hydrologically sustainable pathways. • Investigates collaborative governance for blue space conservation in urban landscapes. • Develops an evolutionary game model for local government-developer interactions. • Identifies key factors influencing the dynamic evolution of the game. • Provides a theoretical framework for effective blue space policy formulation.