Development of Event-Based Pathogen Monitoring Strategies for Watersheds

Threats from pathogens such as Cryptosporidium and Giardia are difficult to protect against, particularly without a clear understanding of the variability of pathogen occurence in space and time. A majority of data collected to date on pathogen occurrence in surface waters has concentraed on characterization of levels under average conditions. Data are lacking on pathogen variability in sub-basins characterized by different pathogen sources, during and following events such as rainfall, or following land use change.

The objective of this project was to use sampling, analytical, and statistical methods to advance the current understanding on the variability of pathogen occurrence and transport through watersheds and to develop methodologies aimed at minimizing risk of waterborne disease outbreaks in drinking water supplies. Specifically, the objectives were to develop and validate a strategy for selection of sampling locations, frequencies, and methods to accurately depict occurence in relation to various sources with watersheds during and after weather, hydrologic, or land use events.