| Title: | Quantifying pathogen sources in streams by hydrograph separation |
| Authors: | Chin, D.A. |
| Year: | 2011 |
| Journal: | Journal of Environmental Engineering |
| Volume (Issue): | 137(9) |
| Pages: | 770-781 |
| Article ID: | |
| DOI: | 10.1061/(ASCE)EE.1943-7870.0000394 |
| URL (non-DOI journals): | |
| Model: | SWAT |
| Broad Application Category: | hydrologic and pollutant |
| Primary Application Category: | model and/or data comparison |
| Secondary Application Category: | pathogen fate and transport |
| Watershed Description: | Subwatershed K of the Little River Experimental watershed in south central Georgia, U.S. |
| Calibration Summary: | |
| Validation Summary: | |
| General Comments: | |
| Abstract: | A new technique for quantifying pathogen sources to streams is proposed and demonstrated.
Hydrograph separation is used to partition measured streamflow into surface runoff
and base flow, and characteristic pathogen concentrations are assigned to each flow component
along with a background source flux. The maximum-likelihood characteristic concentrations
and background flux are determined from measured instream pathogen concentrations.
This approach is shown to yield comparable to superior performance in predicting instream
pathogen concentrations compared to much more complex terrestrial fate and transport models.
Application of the proposed approach to six catchments yields Nash Sutcliffe efficiencies
of the log-transformed fecal-coliform concentrations in the range of 0.21 to 0.48. The characteristic
fecal-coliform concentrations in surface runoff are in the range of 200 - 700 cfu/dL and
the base flow characteristic concentrations are in the range of 20 - 100 cfu/dL. It is shown that
the frequency distribution of bacteria concentrations derived from sample measurements can
sometimes differ significantly from their long-term frequency distribution. |
| Language: | English |
| Keywords: | Bacteria; Fate and Transport; Fecal Coliforms; HSPF; Model; SWAT; TMDL; Watershed |