Workshop Report Prioritizes Research Needs for
Criteria Development in Inland Waters 

In February 2009, WERF, with collaboration from the U.S. Environmental Protection Agency, brought together 31 experts on pathogens, indicators, and water quality for a three-day workshop on pathogens in inland waters. The objectives were to determine if coastal research (i.e., to inform the “Beach Act”) can be extrapolated to apply to inland waters, and to the extent more information is needed, to identify and prioritize research that could aid in the development of recreational water quality criteria applicable to inland waters.

The report, Report on the Expert Scientific Workshop on Critical Research and Science Needs for the Development of Recreational Water Quality Criteria for Inland Waters (PATH4W09), includes the workshop participants' summarization of the state of the science and knowledge gaps, and describes what they consider to be immediate and longer-term research priorities. The workshop report is available free under WERF’s open access policy to encourage research and the exchange of information by the water quality community.

The more than thirty research activities identified include short-term research that could be completed by the end of 2010 to inform U.S. EPA’s upcoming  new or revised criteria, and longer-term activities that would be important in future criteria and would lead to improved methods for use in characterizing and protecting inland waters. Of these, three short-term and two longer-term research activities emerged as the top priorities.

Short-Term Research Activities

• Identify and quantify human pathogens in animal feces. This would lead to a better understanding of the potential risks to human health for a broad range of waters impacted by nonhuman sources.

• Optimize and anchor quantitative microbial risk assessment (QMRA) models to observed health effects data obtained from epidemiologic studies and develop QMRA tools for implementation of new AWQC. This would provide an understanding of how predictions from QMRA models relate to human health outcomes observed in epidemiologic studies and would enhance the scientific credibility for using these techniques to predict recreational waterborne illness.

• Examine relationships between quantitative polymerase chain reaction (Q-PCR) and culture-based fecal indicator bacteria (FIB). This would lead to optimizing and standardizing methods for current indicators, and development and validation of methods for alternative indicators and pathogens.

Longer-Term Research Activities

• Characterize fate and transport of animal pathogens in relation to indicators. This would improve our understanding of the factors affecting pathogen transport mechanisms to waterways during runoff events, and facilitate their incorporation into models for predicting inland water quality.

• Conduct epidemiologic studies in inland waters. This work would expand the base of available epidemiologic information to allow for comparisons of health risk in Great Lakes/coastal and inland waters and help to address  key knowledge gaps regarding sources, effects of hydrology, and indicator-pathogen relationships in inland waters within the context of health risks.

Both WERF and U.S. EPA have moved quickly to transform these top priorities in to new research projects. To start, both organizations are undertaking complimentary short term studies on the relationship between qPCR and culture based methods of detection of fecal indicators. EPA is initially focusing on summarizing and analyzing all available data for a comparative evaluation of molecular and culture methods of fecal indicator bacteria in inland waters. EPA is also initiating other efforts to follow up on the input from the workshop, such as evaluating monitoring schemes for flowing waters.

WERF recently issued a request for proposals for research that will generate and interpret new data (using both qPCR and culture methods) on sources, levels, and occurrence of fecal indicator bacteria in inland recreational waters impacted by publicly owned treatment works’ effluents and other discharge source waters.

To learn more these and other WERF research efforts concerning waterborne pathogens and human health, visit us online at

July 28, 2009