Developing a Plan for Identifying Cryptosporidium Sources in the Potomac River

June 28, 2005

Cryptosporidium (acid fast stain). T. Graczyk, Johns Hopkins UniversityObjectives

  • Educate water suppliers and government agencies on Cryptosporidium in the Potomac basin.
  • Provide an overview of sampling and source tracking methods.
  • Discuss a plan of action to better address pathogens in the watershed.


The workshop started with an overview of the Potomac basin, possible sources of pathogens, and available data. Experts in the field of Cryptosporidium sampling, detection, and source tracking then presented information on the available techniques. They also shared information on environmental dissemination of Cryptosporidium and the public health risks associated with Cryptosporidium. Other pathogens of concern that were discussed included giardia and enteric viruses.

The workshop concluded with a discussion of next steps in identifying Cryptosporidium sources and in developing a strategy for controlling their movement into water supply sources. GIS modeling will be used to provide preliminary information on the most likely sources in a pilot study area. It is likely that this will need to be followed up with an expanded sampling program and more detailed analysis of the entire watershed. Research on BMPs will also be needed.

This workshop was held on June 28, 2005. The meeting’s presentations are available to members only.

Additional Information

Bacterial Source Tracking research program, Dr. Charles Hagedorn, Virginia Tech
EPA Microbial Source Tracking Guide