Development of a Wetland Water Balance and the Impact on Groundwater Supply Wells

In cold-climate urban environments such as Guelph, Ontario, the widespread application of road salt for winter safety poses an increasing threat to groundwater quality. Despite the known persistence of chloride in hydrologic systems, critical uncertainties remain regarding its subsurface transport mechanisms—particularly in urban recharge zones where stormwater infrastructure and land use changes intersect. This study, as part of a broader four-phase investigation into the impacts of road salt on urban water systems, focuses on characterizing the hydrological behavior within the Burke Well sewer shed, a critical recharge area for Guelph’s municipal groundwater supply. Using high-resolution LiDAR, climate records, pumping records, field instrumentation, and several physical based models, a hydrologic model was developed to quantify the water balance of this recharge zone. This study aims to simplify the calibration process improving repeatability by accurately estimating critical parameters including an area-weighted evapotranspiration quantity and stream discharge out of the catchment. The calibrated parameters will allow for recharge modeling and forecasting based on pumping records, where the understanding of recharge, ET, lateral flow, and pumping within the catchment zone will inform municipalities on the state of available water in the aquifer and the impact to the groundwater table as demand increases with growing populations.