University of Arkansas, Fayetteville Division of Agriculture


Within a stream, changes in flow rate and local environment can affect the total organic content (TOC) concentrations in the stream water and TOC delivery downstream to water supply reservoirs. Disinfection by-products (DBPs) result from various chemical reactions between chlorine, bromine, and organic carbon in raw water during the drinking water treatment process; DBPs are potential carcinogens and are regulated by the U.S. Environmental Protection Agency. In this project, we measured the TOC concentrations in two streams in the Beaver Lake Watershed: Town Branch and Brush Creek. We then compared TOC concentrations between the two streams and to that observed in streams draining in forested areas to determine if differences in mean concentrations might be related to the streams’ catchment. Finally, using instantaneous discharge at the time of sampling, we determined if TOC concentrations were significantly correlated to the volumetric flow of a stream. The data suggest that there is a positive linear relationship between the TOC concentration and the flow rate of a stream. While TOC concentrations did not vary between sites, TOC flux and yield were significantly different between the two streams.