The water quality investigation of the Cedar Bayou diversion has been based on mathematical modeling of the area to determine the effects of the diversion on hydraulics and water quality under a variety of conditions. The models employed in the study are numerical solutions to the two-dimensional equations of motion and mass balance implemented on a digital computer. Although these models were operated for the entire bay system, results only from the area east of the ship channel and north of Red Fish Reef are displayed in this report, as this is the principal region of interest. This area is indicated on the location map by the coarse shading. It should be reemphasized that the results for this region are obtained by the operation of the one nautical mile models for the entire bay system.