Local Programs. The Metropolitan Council Environmental Services (MCES), and its predecessor organizations, have monitored river water quality in the Twin Cities since the 1930s. Monitoring activities have focused on determining the adequacy of wastewater treatment to ensure public safety and the survival of fish and other aquatic life. The MCES routinely samples 27 sites, mostly on the Mississippi and Minnesota Rivers. Additional sites are located on the St. Croix, Vermillion, and Rum rivers. Sampling stations are usually placed upstream and downstream of the MCES-operated treatment facilities.

All sites are sampled continously using automatic sample devices. Analytical measurements are based on a set of water-quality parameters to track compliance with state standards. Additional parameters such as nutrients, biochemical oxygen demand (BOD), and chlorophyll-a, are also analyzed. Data are available from 1976 and are stored internally at the MCES.

Several citizen monitoring programs, such as the River Water Program, engage in water quality monitoring activities in Minnesota. If the data collected by these programs meet scientific protocols, the PCA enters the data into STORET.