Click on “Download PDF” for the PDF version or on the title for the HTML version. If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options. A Tool for Sediment TMDL Development on Oostanaula CreekPublished by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.org Citation: Pp. 111-116 in Total Maximum Daily Load (TMDL) Environmental Regulations: Proceedings of the March 11-13, 2002 Conference, (Fort Worth, Texas, USA) 701P0102.(doi:10.13031/2013.7537)Authors: J. W. Herr, C. W. Chen, R. A. Goldstein, and J. N. Brogdon Keywords: TMDL case studies, TMDL development and process, field and watershed scale modeling The Watershed Analysis Risk Management Framework (WARMF), a decision support system for TMDL calculation and the watershed approach, was applied to Oostanaula Creek in east Tennessee. Digital elevation data was imported into WARMF, which delineated the 179 km 2 of the watershed into 53 land catchments and 53 river segments. The TVA GIS database provided inputs for land use, animal management, buffer strips, and other watershed characteristics. Meteorological data from 1984 to 2000 from the Athens station was used to drive the model, which simulates surface runoff, groundwater accretion and nonpoint source loads from land catchments. Surface erosion from land catchments and settling, scouring, and bank erosion were considered. Hydrologic calibration was made with USGS gaging data. For water quality, the existing suspended sediment data was collected mostly on dry days. A supplemental sampling program was instigated to collect suspended sediment data during storms with stage sampling bottles. The model was successfully calibrated to match the low base flow concentrations and the high concentrations of the year 2000 storms. The target criterion to support the Fish and Aquatic Life designated use was a 4 day average concentration not to exceed 80 mg/l of suspended sediment 99.8% of the time. There was no point source load of sediment. The nonpoint load from the land was 12,500 kg/d. Bank and bed erosion contributed 31,100 kg/d. The model predicted that the sediment criterion could not be met by reducing the sediment loading from the land surface alone but could be met with major reduction in bank erosion. Results indicate that WARMF is an effective tool for watershed analysis of this type. (Download PDF) (Export to EndNotes)
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