Drought Scenario Analysis Using RiverWare: A Case Study in Urumqi River Basin, China

In this study, we applied RiverWare modeling approach to evaluate the management decisions on surface water andgroundwater diversions in the agricultural watershed of the Urumqi River Basin of Xinjiang in Northwestern China. Arule-based daily time step RiverWare model was developed to simulate the hydrologic effects of different watermanagement alternatives considering irrigation and drainage systems, crop water use, and diversion rules at the diversiondams within the basin. Daily data period from 2005 to 2009 was used to calibrate the model and 2010-2012 was used tovalidate the model. A calibrated daily RiverWare model was then used to evaluate the management decisions underdifferent drought scenarios that generated by using the snowmelt runoff model (SRM) that developed to simulate inflowfrom upstream of Yingxiongqiao gaging station. Two drought scenarios (reduced precipitation and increased temperature)analysis were performed, and the corresponding hydrological variables were compared to the baseline scenario. The resultsindicated that the model adequately reproduced the historical inflows for the Wulabo Reservoir. The scenario analysisresults suggest that the reduced precipitation led to increased groundwater pumping for irrigation both in the spring andsummer. The increased temperature induces a significant increase in surface runoff in the basin and leads to increased cropwater demand within the irrigation district, and however does not necessarily reduce the groundwater pumpage. Wateroperation policies from RiverWare provide guidelines for conjunctive use of groundwater and surface water resourceswithin the basin under different water supply scenarios in the future.

Keywords:

RiverWare Model , Drought Scenario Analysis , Surface Water , Groundwater , Snowmelt Runoff Model (SRM) , Scenarios