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The current MPCA TMDL Impaired waters list currently includes several reaches within the Minnesota River Watershed that are impaired for turbidity, with target completion dates ranging from 2010 to 2020. 

One of the major goals of a turbidity/sediment TMDL is to define major sediment loading sources within the stream reach or watershed.  Determining loading pollutant source allocations is often a contentious topic within a TMDL study due to a number of factors, such as natural background sources, land use, and variability within the watersheds itself.  Various methods have been used to address these issues; however, geomorphic techniques are rising to the surface. 

The MPCA now recommends using geomorphic assessment methods on impaired reaches and watersheds. However, many project managers are not familiar with the geomorphic methods recommended to make an accurate assessment.  This training will cover various geomorphic assessment methods that will help more accurately determine sources, channel stability, and loading contributions.  Using the established matrices and methods will lend credibility to our basin’s TMDL findings and may help establish a more uniform method of TMDL development. This training took place in December of 2008.