Potential recreation benefits that may accrue to the region from various alternative rates of improvement of the waters of the Delaware River were examined, defined, and measured. The area of immediate concern includes 11 counties on both sides of the river. While a number of factors were identified as they affect the four recreational activities under consideration (swimming, boating, fishing, and picknicking), only a few were found to be relatively important. These are income, leisure time, proximity of facilities, and age. Each of these were projected and the resulting changes were related to the extent of participation in the recreation activities. An increase in rate of participation was projected.