Evaluating the impact of percolated reclaimed water from river-channel reservoir on groundwater using tracers in Beijing, Northern China

Abstract As an increasingly important aspect of water management, historical dry river-channels, ponds or lakes are operated for the storage reclaimed as a landscape with need reuse water. However, percolated may have adverse effect on groundwater quality. The aims this work to evaluate potential using various constituents characteristics tracers water, clarify hydrochemical process recharge, and estimate degree which infiltrated has mixed native groundwater. Results obtained by comparing analysis between season wet presented based multivariate statistics analysis, correlation elements, stable isotopes. impact was clustered together higher Cl, K NH 4 –N concentrations, lower Ca concentrations more enriched heavy isotopes unprecedentedly 3D-biplot; types change from Ca–Mg–HCO 3 –Cl, via Ca–Na–Mg–HCO –Cl Na–Ca–Mg–Cl–HCO increasing into groundwater; most useful evaluation fate mixing chloride ion oxygen-18 is accurate than quantify recharge source water; two-end-member model calculate discharged groundwater, proportion in up 94% near unlined riverbed 43% far it. These results demonstrate combined application traditional assess especially 3D-biplot determine spatial quality changes defined different factors.