In this study, discharge and loadings are empirically related to surveyed direct dollar and energy expenses. An energy I/O national model is coupled with a comprehensive Willamette River dissolved oxygen model. Costs estimated for discharges resulting from different pollution control strategies are then transformed by I/O to total energy costs. Three approaches to environmental control for the Willamette were examined. One was that of current enforcement coupled with present levels of augmentation. Another consisted of less augmentation and increased wastewater treatment. Appropriate tactics involved advanced secondary methods of treatment, regionalization of treatment plants, and yet more stringent effluent requirements for industry. The third approach consisted of increased flow augmentation for water quality control. Corresponding treatment was somewhat relaxed.