Estimating the spatial distribution of artificial groundwater recharge using multiple tracers

Abstract

Stable isotopes of water, organic micropollutants and hydrochemistry data are powerful tools for identifying different water types in areas where knowledge of the spatial distribution of different groundwater is critical for water resource management. An important question is how the assessments change if only one or a subset of these tracers is used. In this study, we estimate spatial artificial infiltration along an infiltration system with stage-discharge relationships and classify different water types based on the mentioned hydrochemistry data for a drinking water production area in Switzerland. Managed aquifer recharge via surface water that feeds into the aquifer creates a hydraulic barrier between contaminated groundwater and drinking water wells. We systematically compare the information from the aforementioned tracers and illustrate differences in distribution and mixing ratios. Despite uncertainties in the mixing ratios, we found that the overall spatial distribution of artificial infiltration is very similar for all the tracers. The highest infiltration occurred in the eastern part of the infiltration system, whereas infiltration in the western part was the lowest. More balanced infiltration within the infiltration system could cause the elevated groundwater mound to be distributed more evenly, preventing the natural inflow of contaminated groundwater. Dedicated to Professor Peter Fritz on the occasion of his 80th birthday.

Pathline Density Distributions in a Null‐Space Monte Carlo Approach to Assess Groundwater Pathways

“…At our study site, the results suggest that the pumped water is most likely artificially‐infiltrated groundwater originating from the channel and ponds of the infiltration system, which is consistent with previous field studies (e.g., Moeck et al ; Moeck et al ). Only the central part of the pumping well gallery might be extracting regional groundwater.…”

“…Subsequently, a water mass balance was carried out for each section between each pair of measurement points, where the inflow rate was subtracted from the outflow rate. Infiltration was assumed nil where the outflow equaled the inflow, whereas infiltration from the channel into the aquifer was implied for negative mass balances (Moeck et al ). Based on this calculation, it could be concluded that a large proportion of the infiltration occurs close to the eastern injection point, with only about 25% of the injected water reaching the west end of the channels (Moeck et al ).…”

“…Subsequently, a water mass balance was carried out for each section between each pair of measurement points, where the inflow rate was subtracted from the outflow rate. Infiltration was assumed nil where the outflow equaled the inflow, whereas infiltration from the channel into the aquifer was implied for negative mass balances (Moeck et al 2017b of the injected water reaching the west end of the channels (Moeck et al 2017b). Artificial recharge at the study site is mainly used to minimize the risk of drinking water contamination (due to the proximity of the well field to landfills and industrial sites) and to increase water availability.…”

Potential Benefits of Managed Aquifer Recharge MAR on the Island of Gotland, Sweden

“…The municipality can analyze the results and compare with areas that are not used today but where the presented method shows good potential for MAR. There will be need for validation with numerical modelling and field tests to increase the strength and substance of the results, as shown in, e.g., [15][16][17][18][19].…”

Verteilung anthropogen eingetragener Stoffe im Grundwasser: Ein Fallbeispiel aus der Nordschweiz

“…Der Hauptmuschelkalk besteht aus gut gebankten, meist grauen Kalken und zeigt zusammen mit dem Trigonodus-Dolomit oft starke Auslaugungserscheinungen. Gemeinsam mit der Dolomitzone (Anhydritgruppe) stellt der Obere Muschelkalk den wichtigsten Felsgrundwasserleiter im Untersuchungsgebiet dar und ist von regionaler Bedeutung (Moeck et al 2017b). Die hydraulische Leitfähigkeit liegt bei 1,3*10 -4 ms -1 , kann jedoch räumlich zwischen 1*10 -3 ms -1 und 2*10 -6 ms -1 variieren.…”