Management models for total phosphorus (TP), various nitrogen (N) species, and dissolved oxygen (DO), for polluted culturally eutrophic Onondaga Lake are developed from models presented and tested earlier in this issue (Doerr et al. 1996a, Canale et al. 1996, Gelda and Auer 1996). The management models are applied to test a wide range of remediation alternatives, corresponding to a wide range of reductions in pollutant loading. The analysis focuses primarily on the effluent (3.5 m3/s(80 MGD)) received from an adjoining domestic wastewater plant (METRO), though a reasonable upper bound of reductions in tributary TP load also is considered. The decreases in lake TP and total ammonia (T-NH3) concentrations that could be achieved by partial diversion of METRO, increased treatment at METRO, and reductions in tributary loading, would not be adequate to meet the established in-lake TP goal of 20 μg/L (as a summer average in the upper waters), the T-NH3standard for the lake (0.77 mgN/L for the upper waters in summer), nor the DO standard for the lake's upper waters (daily average ≥5 mg/L). Diversion of the entire METRO discharge around the lake is found to be necessary to meet the T-NH3standard, to approach or meet the TP concentration goal, and to avoid violation of the DO standard in the upper waters during fall. Reductions in the prevailing tributary TP load, of as much as 30%, may be necessary to reach the TP goal.