The report provides theoretical and field experience in water chemistry for graduate students and basic information applicable to Oklahoma and the Southwest, the small Lake Thunderbird watershed was studied and analyzed as an integral system. After background information was established for the 256 sq mi watershed, including the hydrogeologic conditions, a simulation model was set up. Results from the first 250 days of model operation indicate that a column-fed laboratory model can function in a manner similar to the lake in monitoring chemical quality and will thus allow the model study to be maintained for a relatively long time. The model studies show that the chemical quality of the water, under steady state conditions, is similar to that of the lake. The model responds to manipulation of various environmental control factors such as impoundment behavior. It was concluded that a laboratory simulation of an impoundment system as a study and predictive tool is possible and can be applied to other small watersheds in the Southwest. (Author)