Identifying significant groundwater recharge areas and modelling surface and subsurface water balance of the Neebing River

Abstract

This study provides a hydrological function assessment of the Neebing River, a stream that starts in a rural context and transitions to an urban environment that has historically been prone to flooding. Hydrological function assessments have been widely used across the globe, but there is limited information on many rivers in northern Ontario's watersheds. Previous hydrological function assessments provide a basis upon which to develop models based on thematic mapping, surface water and groundwater interactions and isotope sampling to enable the mapping of significant groundwater recharge areas (SGRA) in the Neebing watershed. Infiltration rates were modelled based on available topographic, soil and land use data sets. Statistical analyses of climatological and hydrological variables were used to examine surface-subsurface water interactions on a seasonal and annual scale. Stable isotope sampling was used to investigate groundwater-surface water interactions in some detail. Results of the study show that the Neebing River is highly dependent on the contribution of groundwater to streamflow, especially during dry periods and during the winter. The flow dependency on groundwater highlights the relationship between the Neebing River and the SGRAs within its watershed. The present study advances knowledge of the hydrological function of the Neebing River and provides baseline data for future studies of the impacts of climate change and urbanization on this watershed.