Upper Cannon River Watershed Geomorphology and Hydrology: A Report to MNDNR Fisheries

The upper Cannon River watershed (within the Minnesota Department of Natural Resources' region 4) comprises a 941 square mile drainage area through the Western Corn Belt Plains and North Central Hardwood Forest ecoregions. In 2011, the Cannon River watershed was subject to the Minnesota Pollution Control Agency's (MPCA) Intensive Watershed Monitoring (IWM) process where water quality and biological communities were evaluated to assess watershed health. In 2014, Minnesota Department of Natural Resources (MNDNR) Ecological and Water Resources (EWR) staff conducted geomorphological surveys in the upper Cannon River watershed. In addition to geomorphology surveys, available hydrology data were analyzed to monitor trends in precipitation and runoff. Sites surveyed upstream of Waterville, MN showed relatively good stability due to extensive water storage, undisturbed buffer strips, low slope, and relatively natural sinuosity. One channelized site was surveyed to show effects of channelization in the upper watershed. One site surveyed downstream of Faribault showed instability and high sediment supply due to cumulative impacts from the Straight River watershed and increased non-natural land uses. Though flow gage sites were not available in the upper Cannon River, a site on the Straight River in Faribault and Cannon River in Welch were used for discharge analyses. Hydrology analyses showed that flows are increasing at these locations which has had an impact on river stability.