Minnesota DNR Fisheries has a number of long term monitoring locations throughout the state. In the Waterville area, two lakes are part of the Sustaining Lakes in a Changing Environment (SLICE) program funded through the Legislative-Citizen Commission on Natural Resources.
Madison is a SLICE lake representative of large deep lakes in the western prairie and cornbelt plains ecoregion. Madison has a unique riverine fish community and history. Eurasian watermilfoil became established in Madison after SLICE monitoring began, giving researchers a glimpse into the changes that take place as the plant has become well established.
St. Olaf is a SLICE lake representative of small deep lakes in the western prairie and cornbelt plains ecoregion. St. Olaf has a special regulation on northern pike. Largemouth bass, black crappie, white crappie, and bluegills are the primary gamefish managed on St. Olaf Lake.