Beyond E. coli monitoring: a framework to inform decision-making to address fecal contamination in recreational freshwater

Recreational water quality guidelines are designed to manage public health risks posed by contact with contaminated water. Fecal contamination of freshwater is a potential source of pathogens, therefore, fecal indicator bacteria (FIB) such as Escherichia coli are used as a pathogen proxy. To improve water quality where FIB concentrations exceed guideline criteria, sources of contamination need to be identified and mitigated. There is limited guidance for environmental water managers on how to engage with communities and conduct investigations in a systematic way. Furthermore, there is limited integration of the knowledge and values of indigenous peoples into water resource management. This study outlines a framework for identifying the source of fecal contamination when FIB criteria are exceeded. The framework consists of three steps. Following consultation with (indigenous) communities, Step 1 involves routine monitoring to identify FIB exceedances. Step 2 is initiated where FIB concentrations exceed acceptable limits. Fecal sources and pathways of pollution are identified using fecal source tracking tools in conjunction with site contamination assessments. Mitigations are implemented and water quality monitored to determine effectiveness. Step 3 is initiated where contamination sources cannot be identified, or interventions are unsuccessful or impractical. Where the fecal source(s) is identified but interventions are unable to be implemented, a source-specific quantitative microbial risk assessment (QMRA) is performed on target pathogens associated with the identified source(s). Where the fecal source(s) cannot be identified, a site-specific risk assessment is performed. Strategies, including risk communication, are discussed to incorporate indigenous and community values into water management decision-making.