The recreation situation in the Illinois River Basin is worsening. With population increasing and per capita demand for water recreation activities rising, the combined effect of these two trends is to boost total demand for water-based recreation opportunities at a faster rate than either of the trends producing it. The water resource is relatively fixed in quantity while the quality of the water in the basin is steadily declining as greater and greater demands are made upon the surface water as a dilutant for a growing variety and quantity of municipal and industrial wastes. If major efforts are not forthcoming in the direction of pollution abatement and other water-quality control measures, the outlook for water for recreation in the Illinois River Basin will be (1) a rapidly growing demand for water recreation activities, and (2) a diminution in both the quality and relative quantity of opportunities for basin residents to engage in these activities due to a steady decline in the quality of the water.