When waterways become contaminated with faeces, identifying the source of the pollution is an important part of the contamination management strategy. ESR has a range of molecular and chemical techniques that help to identify sources of faecal contamination of water, whether they are from farms, domestic or feral animals, humans or birds. For example, if an initial test indicates high levels of E. coli, we undertake one or more assays from our ‘toolbox’ of methods. We then develop a strategy for determining the most efficient way to identify the likely faecal contamination source, which includes a ‘decision tree’ outlining the steps to obtaining the most relevant information for the least financial outlay. We have an excellent record of helping local government staff with water management responsibilities to manage and reduce water pollution levels.