A Study On Water Source Allocation For Coping With Drought In Jinghuiqu Irrigation District

Water is a kind of fundamental natural resource and strategic economic resource. Watersecurity been listed as the top of the five most important worldwide issues about sustainabledevelopment. Strengthening the management of water resources, realizing the sustainableutilization of water resources and guaranteeing the sustainable development of socialeconomy have become a global consensus and are the strategic goals that are widelypromoted worldwide.Drought has become more frequent in recent years. As one of the most seriousmeteorological disaster, drought has had had a serious impact on social economy and people’slife, especially on agricultural production. In arid and semiarid areas of north China, shortageand low utilization of water resources lead to poor ability to deal with regional drought, andserious hindered to the development of regional agriculture. As a result of the lack ofscientific and reasonable management, long-term unreasonable exploitation and utilization ofwater resources seriously affect the sustainable utilization of water resources, and cause aseries of ecological and environmental problems.The Jinghuiqu irrigation district is located in Guanzhong Basin.Ant it has a long andglorious history of irrigation The irrigation district uses groundwater for irrigation since the1980’s, And it is a typical well-canal combined irrigated area. The shortage and theunreasonable utilization of water resources lead overexploitation of groundwater and rapidlydecline of the groundwater table. Moreover, some ecological environment problems haveappreaed in some areas. It will inevitably affect the sustainable development of the irrigationregion and the sustainable utilization of water resources if the situation continues. At the sametime, the Guanzhong region where the Jinghui irrigation region lies often occurs droughtevents. According to the results of previous studies, the Guanzhong region will have a trendof aridification. The problem that how to deal with the situation that continuous droughtevents occur in the future is what we must face.On the basis of the collected information, the results of previous studies and fieldsurveys, this report analyses the current problems of the Jinghui irrigation region, establishesa two-dimensional transient simulation of the groundwater flow, and corrections and tests the model. Then under the current condition of water resource, the groundwater table of theirrigation district in2030is predicted by the model. Finally, water resources are allocatedafter running the Dongzhuang reservoir. And this will ensure regional groundwater table canrecover the reasonable level and stay steady.In this way, the ability of copying with sustaineddrought will be improved. After studying, the conclusions are as follows::(1) Based on historical data analysis results, runoff of Jing River, water diversion andrainfall of the irrigation district will decline. This means that water shortage in irrigationdistrict will be more serious. If the way of water resource utilization continues, groundwaterwill still be over exploited which causing groundwater table to continue to decline.(2)It can conclude from the equilibrium analysis of the groundwater of the irrigation areathat the main supply source of groundwater comes from rainfall, agricultural irrigation andcanal seepage; the main discharge way is artificial exploitation which accounts for more than80%of the total excretion. Groundwater of the irrigation district is in serious negativeequilibrium.(3) Using the model to predict the groundwater level. The results show that groundwaterdepth in the most of the irrigation district in2030is above20m and groundwater tablecontinues to decline.(4)After building and running the Dongzhuang reservoir in2030, water-supply of thereservoir can meet the demand of agricultural irrigation. Therefore, we can take the Qushoureservoir and the Dongzhuang reservoir as the water sources in the irrigation district, and thenallocate the irrigation water. The allocation stage of water source is divided into recoverystage and stable stage. At recovery stage, water allocation according to the gross waterrequirement of crop growth. And according to the geomorphic conditions and embeddeddepth of groundwater, the irrigation district is partitioned. The results showed thatgroundwater table of the irrigation district could return to a reasonable level by2042, thegroundwater depth mostly is5-10m, and minority more than15m. At stable stage, throughthe controlling the use of surface water and groundwater the stability of groundwater table inthe irrigation district can be kept.