|Cho, Kyunghwa - Korea Research Institute|
|Oliver, David - University Of Stirling|
|Muirhead, Richard - Agresearch New Zealand|
|Park, Yongeun - Us Forest Service (FS)|
|Quilliam, Richard - University Of Stirling|
Submitted to: Water Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/28/2016
Publication Date: 4/29/2016
Citation: Cho, K., Pachepsky, Y.A., Oliver, D., Muirhead, R., Park, Y., Quilliam, R., Shelton, D.R. 2016. Modeling fate and transport of fecally-derived microorganisms at the watershed scale: state of the science and future opportunities. Water Research. 100:38-56.
Interpretive Summary: Modeling is an essential tool for the monitoring, management and predictions of microbial quality of surface waters at the watershed-scale. Such modeling has seen substantial development during the past ten years. The objective of this work was to summarize views of an international group of experts on the state of the art in this field and to outline needs and feasibility of further developments. We found both similarity and differences in models developed and used in major industrial countries. Data availability, spatial scale, and the purposes of modeling were the main differences between models. The multitude of watershed applications addresses microbial quality of recreational, irrigation, process, fishery, and other water types. Improvements of models will require, in particular, a better understanding of microbial export from spatially distributed sources, and microbial survival in sediments, soil, and other media in contact with water sources. The results of this work are expected to be of use for a wide group of developers and practitioners in the microbial water quality field. They present a comprehensive accounting of the advantages, limitations, and utility of watershed-scale modeling applications in environmental assessments that include microbial water quality.
Technical Abstract: Natural waters provide habitats for various groups of fecal indicator organisms (FIOs) and pathogenic microorganisms originating from animal manures and animal waste. A number of watershed modeling works have been carried out to have a better understanding to the fate and transport of fecal indicator organisms and protozoa oocysts in watersheds as well as to determine whether microbial water quality standards can be satisfied under site-specific meteorological and/or management conditions. Overall, modeling microbial fate and transport in watersheds has made substantial progress during the last 10 years. Our objective was to review this progress. We evaluate the modeling approaches that have been adopted to account for FIO and oocysts fate in animal waste, soil, waters, and sediment, their transport in watersheds, and discuss their contribution to watershed-scale modeling. Consideration is also given to the utility of existing process-based models for predicting microbial concentrations in watersheds. Finally we propose an outlook of research needs to improve our modelling of microbial water quality alongside an assessment of the feasibility of emerging modeling opportunities. This comprehensive review will therefore provide future steer to help improve modeling of fecal indicators and pathogens in surface water and assist in developing appropriate risk management strategies to reduce impairment of freshwater sources.