Waterway monitoring crews have begun their work throughout the state to track the health of the state's rivers, streams and lakes over a 10-year period.
It's the third year in the effort, which is being funded by the Clean Water Legacy Act that generates money through a 3/8-cent sales tax.
Most of the monitoring will focus on Minnesota's 81 major watersheds so the Minnesota Pollution Control Agency can get a complete picture of the conditions within each system.
In the northern half of Minnesota, monitoring crews will work this summer in the Big Fork River, Crow Wing River and the Bois de Sioux/Mustinka River watersheds. In the south, crews are focusing on the Minnesota River near Granite Falls and the Mississippi River near Winona and the Twin Cities.
MPCA officials said crews will also sample 150 sites picked at random to determine the condition of streams statewide.
If the monitoring teams find that a certain waterway is impaired, the MPCA will look at what's causing the problems and find a way to correct them.