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An Overview of Bacterial Source Tracking - Methods and Applications Douglas Moyer & Kenneth Hyer U.S. Geological Survey Richmond, Virginia October 17, 2003. An Overview of Bacterial Source Tracking - Methods and Applications Douglas Moyer & Kenneth Hyer U.S. Geological Survey
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An Overview of Bacterial Source Tracking - Methods and Applications Douglas Moyer & Kenneth Hyer U.S. Geological Survey Richmond, Virginia October 17, 2003 An Overview of Bacterial Source Tracking - Methods and Applications Douglas Moyer & Kenneth Hyer U.S. Geological Survey Richmond, Virginia October 17, 2003
303(D) List of Impaired Waters • More than 600 stream/rivers • listed as impaired • More than 50% listed for • violations of the fecal • coliform bacteria standard Determine the sources of fecal coliform bacteria causing the violations
UNKNOWN KNOWN Indicator Water Source Organism Samples Samples Indicator Organism pattern pattern pattern pattern pattern pattern A C Dog Goose B Human Bacterial Source Tracking
BST Methods Comparison Study • Study involves a direct comparison of 7 BST methods. • Each researcher is provided a collection of known library isolates. • Evaluation is based on the utility of each method to identify 200 blind isolates (which were from known sources). • Five Genotypic Methods (and investigators) • Ribotyping using two different enzyme sets (George Lukasik, Mansour Samadpour) • Pulsed-field Gel Electrophoresis (West Virginia Department of Agriculture) • rep-PCR using two different primer sets (Howard Kator, Don Stoeckel) • Two Phenotypic Methods (and investigators) • Antibiotic Resistance Analysis (Bruce Wiggins) • Carbon Substrate Utilization (Chuck Hagedorn)
Methods Comparison - Conclusions • In a general sense, we found that: -In this study, under these conditions… These results may not be universal! -All methods did not produce comparable results; some methods were more successful than others. -Results will be published this winter, likely in Environmental Science and Technology. A draft manuscript is currently in the review process. • This is one of a few comparison studies being done. Need to see what some of these other comparison studies determine... • Without stepping through the results, we can offer these conclusions/recommendations: -Perform considerable QA/QC in your BST work! This may include: (1) analyzing blind collections of known isolates, (2) use of multiple BST methods, and (3) the use of other tracers to support the BST work. -Source tracking has tremendous potential, just be cautious in your application of this new technology.
Field Application of BST • Three Streams included on the DEQ 303(d) list: Accotink Creek, Christians Creek, and Blacks Run • Field Data Collection • Water-sample collection • Baseflow - 8 samples every 6 weeks • Stormflow - 10 samples during 5 events • Source Samples • Bacteria Source Tracking Analysis – Ribotyping • TMDL Development Using HSPF
35 Accotink Creek 30 Christians Creek 25 Blacks Run 20 Percent of Known 15 10 5 0 Cat Dog Deer Duck Horse Cattle Goose Human Poultry Sea Gull Raccoon BST Results:By Individual Contributor
0.25 0.04 Caffeine Cotinine 0.2 0.03 0.15 Cotinine (µg/L) Caffeine (µg/L) 0.02 0.1 0.01 0.05 0 0 Accotink Creek Christians Creek Blacks Run Validation of BST:Human Signature
Other Other Dog 12.0% 21.1% Waterfowl 9.0% Waterfowl 37.0% 38.7% Deer Dog 10.0% 13.3% Deer 1.4% Human Raccoon Raccoon Human 17.0% 15.0% 5.4% 20.1% Results of BST:Comparison of Accotink Creek and Four Mile Run Accotink Creek, BST Results Four Mile Run, BST Results (N=279) (N=278)
Fecal Coliform Modeling Process Fecal Coliform Concentration & BST Data Fecal Coliform/Manure Application/Deposition Wash-off by Overland Flow Die-off Land Surface Point Source Release of Bacteria with Interflow Blacks Run Shallow Sub-Surface Storage Release of Bacteria with Baseflow Deeper Sub-Surface Storage
Fecal Coliform Calibration Observed BST Initial Model Calibration Final Model Calibration 40 35 30 25 20 15 10 5 0 CAT DOG DEER DUCK GOOSE HUMAN MUSKRAT RACCOON Percent Signature
USGS Contact Information Watershed Model Doug Moyer 1730 E. Parham Rd Phone: 804-261-2634 Richmond, VA 23228 Email: dlmoyer@usgs.gov Bacterial Source Tracking Ken Hyer 1730 E. Parham Rd Phone: 804-261-2636 Richmond, VA 23228 Email: kenhyer@usgs.gov Resources on the Web http://water.usgs.gov/owq/microbial.html