The Pearson Creek Watershed (61 km2) drains both the City of Springfield and more rural, agricultural areas. Water quality of the creek is affected by unknown toxicants potentially responsible for the decline in aquatic life. The purpose of this study is to complete an assessment of pollutant concentrations found within the watershed and to support efforts to develop a Total Maximum Daily Load (TMDL) for Pearson Creek. From November 2007 to December 2008, 15 sampling sites were monitored 2 to 3 times per month during both baseflow and runoff conditions. Analtyes of interest included total nitrogen, total phosphorus, total lead, total cooper, total zinc, Escherichia coli, total coliform, and total suspended solids. Water quality parameters [...]