Report on the Investigations of the Pollution of the Minnesota River from Above New Ulm to the Junction with the Mississippi River at Mendota

This 1934 report tells of the effects of pollution on the Minnesota River for a period prior to the installation of many of the waste water treatment plants. During this period the majority of sewage and industrial wastes were being discharged directly into the river system with no form of treatment. Accurate means of analysis were not available so most of the data provided is in the form of visual observations. It was determined that the section of the Minnesota River tested was unsafe for human or livestock contact. This was due inpart to the high levels of pathenogenic bacteria in the system. Also, fish kills were common and the scientists attributed these occurrences to low dissolved oxygen (due to high BOD) and toxic industrial discharges. The Board of Health determined that it would be necessary to provide waste water treatment for all municipalities and industries along the Minnesota River.