Submitted to: United States Department of Agriculture Technical Bulletin
Publication Type: Popular publication
Publication Acceptance Date: 10/15/2009
Publication Date: 12/28/2010
Citation: Kim, J., Pachepsky, Y.A., Shelton, D.R. 2010. Sediment-Associated Bacteria Release and Settling In SWAT bacteria routing: Model and SWAT add-on manual. United States Department of Agriculture Technical Bulletin. Available: http://www.ars.usda.gov/Research/docs.htm?docid=21090. Interpretive Summary: Streambed sediments have long been known to harbor substantial populations of E. coli bacteria. However, effects of the bacteria release due to sediment resuspension on microbiological quality of surface waters have not been addressed in water quality prediction and assessment tools. We developed the bacteria release and deposition module for the ARS-USDA model SWAT. The model and the SWAT code modifications are described in this manual. These results are important for design, evaluation and implementation of conservation and best management practices nationwide in that the work has addressed important source of water quality indicator bacteria in freshwater streams which is currently overlooked.
Technical Abstract: Streambed sediment has been attracting attention as a reservoir for bacteria, including pathogenic strains. Soil and Water Assessment Tool (SWAT2005) includes bacteria transport subroutine in which bacteria die-off is the only in-stream process. The purpose of this technical bulletin was to describe SWAT bacteria routing module by including sediment-associated bacteria release and settling in streams. Streambed bacteria release and settling were computed based on the sediment resuspension and deposition modules in SWAT. The model and the necessary modifications of the SWAT 2005 code are presented.