Simulation of lake-watershed systems II. Application to Baptiste Lake, Alberta, Canada

A lumped response watershed model is applied to the simulation of lake chemistry and surface levels of Baptiste Lake. The Baptiste Lake watershed is located 130 km north of Edmonton, Alberta, Canada, and has an areal extent of ∼318 km2. The watershed is covered primarily by drift which is underlain by shale in the vicinity of Baptiste Lake and sandstone and shale west of the lake. The simulation model, described in the earlier paper in this series, is utilized to simulate a 6-yr. history of lake level fluctuations to within a mean absolute difference between the measured and calculated lake elevations of less than 0.1 m. Although only a 2-yr. record of lake chemistry was available, the mean difference between actual and simulated lake salinity is ∼7 mg/l. The model illustrates the importance of groundwater discharge to Baptiste Lake. It is estimated that an average of 13% of all annual inflow (varying between 7% and 22% annually) to Baptiste Lake consists of groundwater.