The Attenuation And Recovery Of A City’s Riverside Source’s Water Supply

Water quantity and water quality security are two major problems of water supply safety.This paper deeply studies a region’s water supply attenuation and recovery relying on the director’s project of the groundwater evaluation.Based on the data research and field survey,we deeply analyse the study area’s hydrogeological conditions,construct the concept model of the area,according to the recharge/discharge factor analysis and water balance calculation,we determine the 2001 (early time of water intake) and 2014(recent time of water intake) various types of water supply,water excretion ratio;then we analyse the major control factor which causes the region’s water supply capacity decay.In the light of the factor,this paper puts forward the measures to restore the water supply capacity of the water source and uses the numerical simulation method to quantitatively analyze the water recovery scheme.Finaly through comprehensive comparison,we determine a better recovery scheme.The main results obtained in this research are as follows:(1) Defined the hydrogeological conditions in the study area,including groundwater storage medium、 groundwater’s recharge、runoff and discharge conditions、dynamic changes of groundwater level in different equilibrium stages and parameters of aquifer hydrogeological.(2) Through the analysis of water balance,we obtain the water supply factors and the discharge factors of the groundwater in the study area.Recharge factors include rainfall infiltration recharge、ditch infiltration recharge、irrigation infiltration recharge、upstream aquifer lateral recharge and river replenishment,excretion fators include artificial exploitation of drainage and groundwater evaporation.Then we use the water balance method to calculate the water quantity of each recharge factor and each excretion factor contributes,and according to the data,we judge the main control factors which lead the attenuation of the water supply capacity.(3) In the light of the major control factor,we propose two programmes to recover the capacity of water supply,including increase the thickness of the water intake section and resume the river’s intensify supply capacity.Then we research the degree of recovery of water supply capacity in differernt thickness of water and differernt river stage.(4) For the above two kinds of restoration programme,we make the comparison in the aspect of water quantity recovery degree、engineering cost and water quality,we draw the conclusion that restore the river’s intensify recharge capacity is better and put forward the suggestion for the possible problems in the implementation process of the program.This study not only has practical significance for the safety of drinking water supply in the city,but also has a reference value for the recovery of supply capacity of drinking water which is similar to this riverside source.