Open Access Thesis
Nutrient pollution of water--Cedar River Watershed (Minn. and Iowa); Water--Pollution--Cedar River Watershed (Minn. and Iowa)--Measurement; Nonpoint source pollution--Cedar River Watershed (Minn. and Iowa);
A study was done on four tributaries to the Cedar River to determine nutrient concentrations, loads, and the contribution of each watershed per unit area. The Cedar River watershed is primarily agricultural land and extends from southern Minnesota to southeastern Iowa. Past studies have indicated that this watershed is a major contributor of nitrate to the Gulf of Mexico via the Mississippi River. This eutrophication is the cause of the hypoxic Gulf. From April 13, 2010-September 21, 2010 samples were taken from four tributaries of the Cedar River. Discharge data were taken from USGS gaging stations along with a method developed on ungaged sites. Samples were analyzed for parameters influenced by agriculture such as total dissolved solids, total suspended sediments, nitrate, and chloride. Average concentrations, total loads, and pounds per acre (lbs/acre) contributions of each parameter were calculated for each subwatershed during the approximately 6 month period of study. The tributary with the highest average nitrate concentration was the West Fork Cedar River with 33.22 ppm. However the Upper Cedar contributed the most nitrate load with 31,994 tons. When all of these factors from each pollutant are taken into consideration it appears that the Upper Cedar River had the most impairment followed by the Shell Rock River, West Fork Cedar River, and finally the Winnebago River.
Year of Submission
Master of Science
Environmental Science Program
1 PDF file (ix, 77 pages)
2014 - Jacob Donaghy
Donaghy, Jacob, "Calculating nutrient loads from four tributaries of the Cedar River in Iowa" (2014). Theses and Dissertations @ UNI. 37.