Land use effects on groundwater recharge in the prairies

Abstract

Land use effects on groundwater recharge in the prairies are poorly understood. Recharge rates are low, driven by snowmelt runoff in the spring. Errors in measurements of water balance components are often greater than the volume of recharge. Land use effects on snowmelt runoff were determined by comparing runoff volumes at two scales: point scale fields and watershed scale with remote sensing. A paired plot study was compared using the water table fluctuation and chloride mass balance methods to estimate groundwater recharge rates for two spring snowmelt events. It was found that cropland fields had greater snowmelt runoff volumes, and thus likely greater groundwater recharge rates. However, given differences in topography and aspect, the water table fluctuation and chloride mass balance techniques were inconclusive with regards to land use effects on groundwater recharge. To increase recharge rates, converting higher topography fields to croplands or installing snow fences along depressions to capture more snow are viable options.