Water quality impacts of shifting the shoreline discharge of a major (3.5m3/s) domestic wastewater treatment faclity (METRO) on polluted, eutrophic Onondaga Lake, NY, to a deep-water location are evaluated with three mechanistic water quality models. Transport and mixing inputs for the simulations are specified from the output of a separate hydrothermal model (Owens and Effler 1996). Model simulations indicate, that by trapping enriched effluent in the lower layers, summertime concentrations of total phosphorus (TP) and total ammonia (T-NH3) would decrease in the upper mixed layer (0 to 4.5 m depth interval). Further reductions in the concentrations of those constituents would be realized by reducing sediment release, through maintenance of oxia in the hypolimnion. However, the decreases that could be achieved with the prevailing METRO effluent characteristics would not result in substantial reductions in phytoplankton growth nor prevent violation of the T-NH3standard. An extremely high degree of nitrification would be needed at METRO, particularly during the late fall to early spring interval (e.g., T-NH3, concentrations < 3.6 mgN/L in effluent), to avoid violation of the T-NH3standard. Oxygen concentrations in the existing METRO effluent would have to be maintained at approximately 70 mg/L to ensure the hypolimnion remains oxic. To provide oxygen concentrations ≥5 mg/L in the hypolimnion, oxygen concentrations of = 130 mg/L would have to be maintained in METRO's effluent.