Unveiling impacts and optimal strategies of water-saving system for integrated water resources management in a water-scarce watershed

In this study, impacts and optimal strategies of water-saving system are identified through developing a novel stochastic bi-level programming-based water saving and trading simulation model for water resources regulation (SB-WSTM). The link between socio-economic and water resources under uncertain conditions, as well as participation of government water-saving subsidy and water-saving facilities (i.e., sprinkler irrigation, micro-irrigation, low-pressure pipe irrigation) are elaborated. The SB-WSTM is then applied to Dagu River watershed in China with water-scarce characteristics for demonstrating its efficiency. The responses of the water resources system to water-saving facilities and subsidies are disclosed quantitively. Micro-irrigation facility construction is recommended to cope with extremely dry condition; 50% of subsidy rate combined with 70% of efficient irrigation area is the optimal water-saving scheme based on multi-criterion analysis and should be recommended. Recognizing the effect of water saving, generating efficient water allocation patterns, and taking water-saving strategies are key adaptation means for water system sustainable utilization.