Evaluation Of Groundwater Resources In Dagu River

Qingdao is water shortages in the north of our country. The contradiction is sharpbetween supply and demand of water. Dagu River is one of the areas with abundantwater in Jiaodong area and is the biggest river in Qingdao, playing a very importantrole in easing water shortages. Taking groundwater source in Dagu River as a case,water quality conditions are analyzed and the groundwater flow and solute transportnumerical models are constructed by using survey data and the groundwaternumerical software Visual MODFLOW. Under the condition of present status, thispaper calculates the groundwater exploitable resource and forecasts the trend of thepollution of nitrate variables.On the basis of fully collecting and analyzing relative materials such as geology,hydrogeology and environment of the study area, the paper explains systematicallythe cause and litho logy of the main stratum in the research area, and analyzes the lawof recharge, runoff, drainage and dynamic characteristics of the groundwater. Afterconfirming the range of simulation district and object layer for calculation andgeneralization hydraulic characteristics, vertical and lateral boundary, a groundwatermathematical model is set up. Visual MODFLOW which is based on finite differencemethod is employed to solve the numerical equations. This simulation used the waterlevel observed value of selecting January of2009to January of2011to identify andinspect the model. The fitting effect is all right, and it explains that the determinationof aquifer structure and hydro geological parameter, the model can be used inforecast.Maintaining existing industrial agriculture layout unchanged, the groundwaterexploitable resource is15426.8×10~4m~3in wet year. The groundwater exploitableresource is13077.6×10~4m~3in medium precipitation year. The groundwater exploitable resource is10899.87×10~4m~3in draught year. Based on the prediction ofthe water table between2011and2010, this paper forecasts the change of water tableand forecast the groundwater resource in2020will be more than the maximumallowed water extraction in draught year under designing plan.Water quality conditions are analyzed to determine pollution rules and influencefactors in Dagu river plain, by the use of the study area of30monitoring wells from2007to2009. Analysis shows that the main pollutants in the area for nitrate nitrogen,and the main cause of the contamination is agricultural pollution. Pollution areaconcentrated in Pingdu and Laixi where agriculture relatively developed.