Understanding the contribution of nitrate-rich groundwater to surface water is critical in agricultural watersheds, particularly where streams are baseflow-dominated. This study investigates the spatial and temporal variability of nitrate discharging to Alder Creek, a small agricultural stream in southern Ontario, Canada. A 100 m gaining stream reach was identified based on previous temperature mapping and instrumented with 24 mini-piezometers and 8 shallow monitoring wells installed within the upper 50 cm below the stream bed. As part of the current work, groundwater samples were collected across seven sampling campaigns spanning 18 months to investigate the spatial and temporal patterns in nitrate discharge to Alder Creek. Results show that groundwater nitrate concentrations were spatially heterogeneous but remained relatively temporally consistent across sampling events at individual locations. Groundwater conditions were predominantly oxic, with trace iron and manganese signatures suggesting limited denitrification potential. These findings appear to highlight the potential dominance of spatial heterogeneity over temporal variability in nitrate delivery from groundwater to Alder Creek. Spatial patterns in nitrate concentrations and fluxes appear to reflect localized preferential pathways at isolated discharge points along the gaining portion of the studied reach. This study emphasizes the importance of fine-scale monitoring in characterizing groundwater discharge patterns to streams in agricultural catchments. Initial results suggest that the groundwater nitrate concentration distributions appear to remain relatively consistent over time. Ongoing work is exploring nitrate mass fluxes entering and exiting the study reach, and groundwater discharge patterns via isotopic and age-dating tracers and geophysics.