Spatial and temporal variations in water quality and biological conditions were investigated in the lower 77 miles of Kentucky Reservoir in a series of monthly surveys conducted from February to September 1982. Factors investigated included dissolved oxygen and nutrient dynamics, algal community structure and standing crop, primary productivity, limiting nutrients, and water chemistry. Significant longitudinal and seasonal variations were observed for most parameters. Only minimal variations were observed with depth. Although thermal stratification was not observed, weak dissolved oxygen stratification did occasionally develop. Reservoir hydrodynamics appears to have pronounced effects on water chemistry and algal productivity.