Groundwater and surface water interactions in the Jock River watershed, Ottawa, Ontario were investigated during the 2015 growing season using end-member mixing analysis (EMMA). The Jock River sample sites were integrated into a spatially distributed single linear mixing model. Spatial and temporal variations amongst the dominant sources of baseflow were observed in the Jock River watershed. Baseflow generation across the Jock River watershed showed a dynamic relationship between the sources contributing to baseflow and antecedent moisture conditions. The wetland end-member was the dominant source of baseflow in the upper watershed and showed little temporal variation in end-member contributions throughout the growing season. Strong linear correlations between the average proportion of the wetland end-member and natural features (forest, wetland and organic deposits) were observed. Results highlight the importance of different landscape components contributing to baseflow across the watershed, specifically the importance of wetlands at mitigating high and low flow conditions.