Feasibility Analysis Of Inter-basin Water Transfer Of Dalian City Considering Climate Change

Inter-basin water transfer project transport the surplus water from water-rich areas to water-deficient areas, thus, the regional water shortage problem could be alleviated in some way. Affected by climate change, water resources in the water-rich areas may be reduced. At the same time, water consumption increased in most cities. Under those two disadvantages, it is hard to certain the water-rich area could continue transport water to other places. Dalian City belongs to the area where seriously lack of water, local water resources plus the water transformed from Dahuofang Reservoir can basically meet recent water demand. But along with economic and social sustainable development, Dalian City will continue to face the water shortage crisis forwardly. Dalian city has always been exploring solutions to solve water problem. Inter-basin water transfer project is one of the main solutions, the water supply guarantee rate of H Reservoir and Dahuofang Reservoir is the main basis to judge the feasibility of this solution. Therefore, this paper focus on the effect of climate change to water resourcese, and based on the SWAT forecast result of the Biliuhe Reservoir and H Reservoir estimated the the forward water supply capacity of Dalian City, H Reservoir and Dahuofang Reservoir. At the same time, considering the effect of socio-economic development, respectively based on GM(0,N) and statistical analysis method forecasted the water demand of Dalian City and water diversion area. And then based on the result of water supply and demand balance analysis about Dalian City and water diversion area, from the perspective of water supply guarantee rate, finished the analysis about the feasibility of the forward inter-basin water transfer project in Dalian City. The main research contents and results are as follows:(1) The SWAT hydrological model of H basin and Biliuhe Basin had been built based on several kinds of data, including DEM, land use, soil and meteorology. Then the two SWAT models were been calibrated and validated by using historical hydrological data. Next. the efficiency of these two models had been evaluated by Nash-Sutcliffe (NS) and the correlation coefficient (R2). The results showed that the SWAT models of H basin and Biliuhe Basin are good enough to forecast. Based on the calibrated SWAT models, the inflow of H Reservoir and Biliuhe Reservoir are been forecasted with the predicting outcomes of HadGEM2-AO model. The forecasting results show that the forward inflow of H Reservoir could be 121.71?137.48 m3/s, the forward inflow of Biliuhe Reservoir could be 16.10-17.41m3/s.(2) Based on GM(0,N) built the the water demand forecasting comparative models with two slightly different sets of data, the study result quantitatively explains that choosing the data series which represent better could improve the forecast accuracy. And then considering the effects of socio-economic development, predicting the water demand in urban areas of Dalian City in 2030 could be 14.06-16.24 billion cubic meters.(3) Refer to the runoff forecasting result of Biliuhe Reservoir and status of water resources in Dalian City, estimated the the forward water supply capacity of conventional water about Dalian City could be 12.19-13.19 million cubic metres. Combining the forecast result of the water demand in urban areas of Dalian City, predicting the long-term water shortage of conventional water in Dalian City under RCP4.5 and RCP8.5 respectively would be 0.87-3.05 million cubic metres and 1.87-4.05 million cubic metres. On the other hand, predicting the local water demand of H Reservoir and Dahuofang Reservoir could be 29.23 million cubic metres by statistical analysis method. Taking the runoff forecasting result of H Reservoir for reference, estimated the the forward water supply capacity of water diversion area could be 30.00-36.98 million cubic metres. The result of water supply and demand balance analysis about water diversion area shows that the water diversion area can meet local forward water demand. Expect that, under RCP4.5 scene it still could surplus 0.77 million cubic metres, and under RCP4.5 scene it still could surplus 7.75 million cubic metres. According to the situation of water shortage in receiving area and water redundancy in water transfer area, and comparing the possibility of the two climate scene, ultimately come to the conclusion:the water transfer project could be carried out when just considering the water supply guarantee rate.