Diffuse pollution from agriculture presents a risk to microbial water quality and the security of ecosystem surfaces linked to clean and safe drinking water. This risk is likely to rise as the frequency and intensity of storm events increases, largely as a result of climate change. SCIMAP is an existing risk-mapping framework that has been successfully developed and deployed by the catchment management community to predict fine sediment and nutrient risk to watercourses. The SCIMAP approach is built on the premise that sources of pollution are only a risk to watercourses when they are hydrologically connected through the landscape to an aquatic receptor – this recognises the well-established diffuse pollution concept of critical source areas. In this project SCIMAP will be modified to optimise it for prediction of faecal indicator organism (FIO) risk to receiving waters. Key challenges for SCIMAP FIO are to account for the temporal variations in FIO risk due to the dynamic survival patterns of microbial pollutants in the environment and to derive travel times from source to water bodies for FIOs and pathogens too. We will then explore the framework with different scenarios of climate and land-use change to predict how the risk of microbial pollution from agriculture might change in the future.

Key research questions:

  1. How do hydrological pathways that connect pathogen source to receptor vary in space and time across different catchment typologies and how does this impact on microbial travel times?
  2. To what extent does the probability of microbial die-off vary for different environmental conditions during transfer from catchment source to aquatic receptor?
  3. How do we integrate microbial behavioural characteristics (both indicator and pathogen) into the SCIMAP framework to develop a conceptual and procedural risk-based model?
  4. How will the export of microbial pollutants from the landscape alter under projected climate change?