The increased delivery of water, sediment, and nutrients to the Minnesota River from the Le Sueur and nearby watersheds now represents an important water quality problem that the State of Minnesota is addressing.  LeSueur River Integrated Sediment Budget Final Report

Although sediment is a natural constituent of rivers, excess loading to rivers and streams is a leading cause of impairment and biodiversity loss.  Sediment loading increased greatly as a result of vast landscape changes over the past 150 years, yet the dominant source of sediment has shifted from agricultural soil erosion to accelerated erosion of stream banks and bluffs, driven by increased river discharge.  Large Shift in Source of Fine Sediment in the Upper Mississippi River