Abstract
The brief history of management and rehabilitation of eutrophic lakes and reservoirs in North America has gone in 4 directions: (1) solving the limiting nutrient controversy; (2) testing in-lake and watershed rehabilitation methods; (3) examining the roles of biology in determining lake trophic state; and (4) involving lake users and owners in lake research and management. Two major outcomes have been reached: (1) a great increase in understanding of eutrophication, its impacts on humans, and its solutions; and (2) major developments in understanding lake and reservoir ecology through a holistic rather than reductionist research model. Diversion and/or control of point and nonpoint sources of nutrients, silt, and organic matter, including internal nutrient recycling, were shown as necessary to lake improvement, but eutrophication problems often continue or return because social, political, and economic forces can thwart treatment effectiveness and longevity. An example is the “American Diet” that drives agricultural pollution of freshwater. The lake management and rehabilitation process should incorporate social scientists into its paradigm so that we can learn how to encourage humans to make choices and have behaviors better suited to successful longterm lake protection and management.