Security System of Water Quality for Groundwater Recharge with Infiltration Basin and Reclaimed Water

It is significant to ensure safe aquifer recharge using reclaimed water that meets the safety requirement for the sake of recovering aquifer depletion, relieving the conflict between water demand and supply, and controlling the serious environmental pollution in China. To improve the water quality of artificial recharge of groundwater using reclaimed water, we develop a security system of water quality for groundwater recharge with infiltration basin and reclaimed water and key technologies based on a series of experiments and theoretic analysis including the recharge site selection and investigation, higher-efficiency and low-cost wastewater treatment technologies, mathematical models of soil-aquifer system and the design of recharge and pumping schemes, monitoring and controlling system of water quality, safety assessment, regulations and standards, and so on. These key factors are interactive and interdependent. The pilot project in Zhengzhou demonstrates the feasibility of the security system of water quality for groundwater recharge with infiltration basin and reclaimed water, with a two-year operation showing that the water quality of the reclaimed water by the waste water treatment system satisfies the surface recharge requirement in the standard of (GB/T 19772-2005) and is better than that of the original groundwater at the site, and groundwater quality after recharge basically reaches grade III of groundwater quality (GB/T 14818-1993). It is suggested to integrate the use of reclaimed water and artificial recharge of groundwater with the utilization of water resources and environmental protection planning, to make and issue relative laws, regulations and standards, and to establish permission regulation on artificial aquifer recharge as soon as possible so as to promote artificial aquifer recharge using reclaimed water.