Abstract: Water quality is an extremely important driver for the ecological processes that support life and influence biodiversity. Land use has a major influence on water quality, with some of the highest impact activities often associated with agriculture and waste disposal. During the past year grab and automated water samples were taken upstream (above landfill) and downstream (below the landfill) to characterize the water quality impacts of land use on the South Fork of Catfish Creek, a tributary of the Mississippi River. This stretch of Catfish Creek allows for an investigation of the impacts of land use and runoff as is adjacent to multiple land uses including both landfill and agricultural lands and was monitored during both base flow and rain-induced runoff events. Significant differences between water qualities characteristics were noted between the differing flow conditions. The samples were analyzed for suspended particulate matter (SPM), various phosphorus forms, nitrates, and heavy metals. Hydrographs showed the relation to changes in concentrations of phosphorus, metals, and sediment change with the flow levels during storm runoff events. Both our sampling sites, above and below the landfill, held levels of phosphorus that exceeded the EPA’s recommendation for ecoregion VII, likely a result of high amounts of agricultural land use in the study watershed. However the form of phosphorus varied between the sites during runoff events in that the upstream sites had more sediment bound P than downstream. This likely results from storage in the stream of sediment bound P as the velocity slows down and the sediment falls out of suspension, which holds long term implications on nutrients storage and transport in this system. Metal concentrations studied show that the holding (retention) pond have much lower concentrations of metals than does the stream – both before and after passing the ponds. As the downstream concentrations of these metals in nearly all cases are similar in concentration than the upstream water it seems very apparent that the ponds, or groundwater flow, are not contributing these potential leachate components into the stream during base flow conditions. Our results indicate that the agricultural lands are likely impacting Catfish Creek landfill with respect to nutrient loading, however the landfill is not adversely impacting the South Fork of Catfish Creek with respect to the analyses examined.
Citation:Nie, Eric T., & Hoffman, Adam R. “Monitoring the Impact of the Land Use Characteristics on the Surface Water Quality of a Mississippi River Tributary.” Poster presentation for the Chlapaty Research Fellowship Program, University of Dubuque, 2013.