THREE-DIMENSIONAL MODELLING OF LAKE ONTARIO HYDRODYNAMICS NEAR PORT HOPE AND IN THE UPPER ST LAWRENCE RIVER

ii The Ontario Clean Water Act (2006) mandated that eight and two municipal drinking water intakes in the Cataraqui Region Conservation Authority (CRCA) and the Ganaraska River Source Protection Agency (GRSPA) jurisdictions respectively, be protected from contaminants released into the surrounding waters through the delineation of Intake Protection Zones (IPZs). Toward these objectives, the Estuary and Lake Computer Model (ELCOM) was applied to simulate the hydrodynamics and contaminant transport in the eastern Lake Ontario and upper St. Lawrence River. Model hydrodynamics were comprehensively validated against field data collected during April-October, 2006. The flow was found to be predominantly wind induced in the southwestern lacustrine portion of the domain and hydraulically driven in the northeastern riverine portion with storm events resulting in river flow reversals. The modeled surface currents were applied to delineate IPZs surrounding the drinking water intakes. Passive tracers were simulated as surrogates for combined sewer outflows, tributary flows, municipal/wastewater and industrial discharges identified by CRCA as threats to drinking water intakes. Wind was found t