Hydropedological investigations with ground-penetrating radar (GPR): Estimating water-table depths and local ground-water flow pattern in areas of coarse-textured soils

In coarse-textured soils, ground-penetrating radar (GPR) can provide continuous, high-resolution records that chart the depth to water tables. The use of this information can increase confidence in hydropedological site assessments and reduce the number of wells needed for water-table depth and ground-water flow determinations. Ground-penetrating radar was used to map spatial and temporal variations in water-table depths and ground-water flow patterns within an unconfined aquifer located beneath an eolian landscape in northwestern Indiana. Compared with the data collected at a limited number of wells, the greater number of observations with GPR provided more comprehensive site coverage and mapped more intricate local ground-water flow patterns. Over a 2-year period, GPR revealed systematic temporal and spatial variations in water-table depths and local ground-water flow patterns.