The effect was evaluated of adding varying amounts of low-nutrient flushing water to one area of Moses Lake, a 6,500-acre highly eutrophic lake in eastern Washington. Cluster analysis of plankton data identified 6 sample groups and species groups. Temporal and spatial variations in community types and standing crops appear to be related to detention time, nitrate content, and available light. The effect of low-nutrient dilution water on lake plankton growth response indicated growth at 90% and 86% lake water. Dye studies, diurnal plankton sampling, and field observations indicate that southerly winds have a great effect on moving algae upstream into upper Parker Horn. Water movements in the lake could be simulated in a distorted Froude law hydraulic model. Removal of algae and nutrients by flushing procedures in Parker Horn and the lower lake would likely be more effective at night. Moses Lake behaves both biologically and hydraulically as though it were divided into several partially isolated regions. A tentative mathematical model has been set up for simulating the productivity and distribution of algae. Flushing Parker Horn with large slugs of low nutrient water may not be effective because of wind action transporting algae and their entrained nutrients back into the Horn together with nutrient regeneration from sediments. (WRSIC-abstract)

Includes bibliographical references (leaves 109, leaf 179-181). Microfiche.