The Regional Nature of Lake Water Quality Across Minnesota: An Analysis for Improving Resource Management

The diversity and number of lakes in Minnesota may be better understood by the use of regional characterizations of lake and watershed information. Recent efforts have utilized the ecoregion approach to define seven regions across Minnesota, four of which contain 98 percent of our lake resources. Typical land use patterns vary regionally as do take water quality patterns. Understanding these patterns will assist lake managers to develop realistic goals and minimize false expectations. Regional assessments facilitate the definition of reasonable goals, expressed in terms of: average summer nutrient concentrations, probability of nuisance conditions ( e.g., estimates of algal bloom frequency), and probability of Secchi transparency ranges for lake resource management-for protective as well as restorative purposes. User perceptions of water quality also may be used to define swimmable conditions to assist in goal setting by lake resource managers.