The Study On Artificial Groundwater Recharge Mode In Demonstration Area Of Hutuo River Gao Cheng City

Due to the excessive extraction of groundwater, groundwater resources of North China Plain are facing shortages and the ecological environment deterioration, therefore how to plan and utilize of water resources reasonably and increase the storage of groundwater become the focus of the study. Using artificial groundwater recharge can recharge the surface water into the aquifer. For quantitative study of artificial recharge of groundwater, the paper took a demonstration area where along the riverside of the Hutuo River as our study area. We established the groundwater recharge model in alluvial-pluvial fan of Hutuo River, based on the model we analysis the recharge effects and the efficiency.This paper analyses the feasibility of artificial recharge of groundwater from three parts: Groundwater storage conditions, the recharge water conditions and the method of groundwater recharge. According to the comprehensive analysis of the engineering and environment restrictions on water level, a limit water level of artificial recharge is determined. By using of MAPGIS spatial overlay technology the storage space in the upper alluvial-pluvial fan of Hutuo River is calculated, it shows that the total storage space is 74.54×108m3.On the basis of full analysis of the hydro geological conditions, groundwater flow characteristics and source sink, groundwater numerical simulation model from 2002 to 2009 in study area was constructed, making use of GMS combine with MODFLOW2005 to solve the model. Groundwater budget of study area were analyzed, this 8 years regional balance instructions the mean groundwater recharge is 7.1×108m3/a, and the mean ground discharge is 10.47×108m3/a, the storage of study area for many years is negative values.Consider the different recharge water and the different artificial recharge mode, two groundwater recharge numerical models have established based on the analysis of the artificial recharge mode of the typical demonstration area. Compared with no artificial recharge after recharge by river, the unconfined aquifer water level increased by an average of 1.83 m in entire study area at the end of 2020, the groundwater balance increased1.32×108m3/a. Using shared node Local Grid Refinement(LGR) technology refined the grid of typical demonstration area. Compared with no artificial recharge, the unconfined aquifer water level increased by an average of 1.87 m in refinement area at the end of 2020, the groundwater balance increased from-2595.98×104m3/a to-1737.13×104m3/a. The predicted results shows that the current situation of water level prolonged decline will control effectively in combination with artificial groundwater recharge. The analysis of effective water storage rate indicated that the permeability and closeness of the study area are all right, and as time increases, the effective water storage rate tend to decrease.Recharge efficiency was analyzed at different wet and dry periods. By using of artificial groundwater recharge techniques, the balance of recharge and extraction in extreme wet years, wet years, median water years, partial dry years and dry years were 4.44×108m3,-4.30×108m3,-6.62×108m3,-8.76×108m3 and-9.32×108m3.The above analysis shows that artificial recharge retard the rate of water consumption and bring larger recharge benefits.