Numerical Simulation Study On Deyang Jingnan Wetland Park Artificial Groundwater Recharge

The research is based on the Urban Wetland Park,the construction of the Ecological River Wetland Park-the artificial recharge system of groundwater.After the completion of the project,the water environment in Deyang can be improved,the leisure place is provided for the citizens,and the micro polluted river water can be improved into the groundwater source with ecological and economic value,and it becomes the important water supply source of the city.The purpose of this study is to understand the actual operation of the project,grasp the changes in the groundwater flow field after the project operation,determine the dynamic characteristics of the groundwater flow and groundwater in the study area,and the dynamic balance of groundwater exploitation,and provide the technical experience and suggestion for the follow-up demonstration project.Based on the artificial recharge system of ecological river-Wetland Park-groundwater,natural infiltration test of infiltration pool,field pumping test,and the basic data of engineering geology and hydrogeological conditions in the study area,the hydrogeological concept model and mathematical model of the study area are constructed.A groundwater numerical simulation model is established by using groundwater simulation software Visual MODFLOW.Through the fitting recognition of the water level process line of the observation hole,the hydrogeological parameters are corrected and the water balance in the study area is analyzed.It shows that the established model can meet the requirements of precision,and can truly reflect the dynamic characteristics of the groundwater flow,and rely on the built model to predict the trend of the groundwater level variation in the simulated area and the recovery of the water in the mining water.The ratio provides reliable parameters for the recirculation prediction model.The following results are obtained in this paper.(1)Practice has proved that based on the Urban Wetland Park,the Ecological River Wetland Park water supply system is running well and the design is reasonable.The operation of the project can achieve the purpose of dealing with micro polluted river water,meeting the needs of water supply and replenishment of groundwater.(2)The study area is mainly distributed in the thrusting and alluvial strata of the Quaternary.The upper part of aquifer is mainly sandy soil or clayey sand,the lower part is gravel gravel layer,and the infiltration condition is better.There is a strong hydraulic connection between surface water and diving.According to the analysis of the water source conditions in the region,it is suggested that the artificial recharge of groundwater,sufficient water source,geological and hydrogeological conditions is superior in the study area,and it is suitable for the construction of artificial recharge of groundwater.(3)The dynamic change trend of groundwater level under the condition of mining and recharge is predicted by the identified model.The overall change trend of the groundwater level in the simulation process is gradually rising.After 1 years,the flow field gradually tends to be stable,and a local ground is formed between the infiltration pool,the mining well and the mian Yuan river.The water flow system,the groundwater is in a positive equilibrium.(4)Simulation calculation shows that the proportion of reclaimed water in mining water will change with time.And the proportion of groundwater returned to groundwater will be stable when it reaches 80%.The exchange of groundwater between the river and the study area is dynamically balanced.