The evaluation of an artificial infiltration and groundwater recharge project in the well field in Roznov pod Radhostem (Czech Republic)

Abstract

The article analyses the permeability of ground surface in order to implement artificial surface infiltration and groundwater recharge by means of surface spraying near the well field, from where groundwater is pumped using a collection gallery in the fluvial gravel terrace. The artificial groundwater recharge project was implemented in order to deal with the periods of drought and related lack of water to be pumped from the fluvial terrace. The area of interest was divided into quasi-homogeneous blocks of surface permeability. Surface spraying was applied in the permeable quasi-homogeneous block. The other low permeable quasi-homogeneous blocks were unsuitable for the application of spraying and groundwater recharge. In the research, two methods were applied to evaluate the ground surface permeability. The first method was in-situ measurements of surface permeability using a two-cylinder infiltrometer in a regular network of points near the collection gallery (drainage channel). The second method was used to evaluate the ground permeability based on soil grain-size curves, where the soil samples were drawn from the same network of points as in the first method. It showed that the majority of the area of interest is sufficiently permeable for the puposes of artificial groundwater recharge, except for three polygons, where the soils were low permeable and where ponds used to occur in the past. Based on the study, surface spraying using water from nearby ponds was applied via an irrigation system, which resulted in increased groundwater levels. In the future, artificial infiltration and groundwater recharge may be applied in analogous geological conditions.