MANKATO (AP) - Homeowners in south-central Minnesota are trying to improve the clarity of lakes in their agricultural region, which have high levels of phosphorus.

Department of Natural Resources Waterville area fisheries supervisor Craig Soupir says that elevated trophic state indexes, a measure of general water quality, are commonplace in southern Minnesota.

There is no catch-all plan to address water quality in the state's lakes because each one requires a specific approach tailored to its characteristics.

Lake Crystal resident Mike Roll formed the Crystal Waters Project, a collaboration between farmers, lakefront homeowners and other stakeholders interested in protecting the lake. In 2015, the group helped eliminate 97,000 pounds of carp, an invasive species contributing to poor water quality. They also recently led a shore restoration project.