Agricultural water and manure application are potential sources of bacterial contamination of fresh produce. A study examined the survival of E. coli in soils amended with different types of manure. Results showed E. coli survived for over 270 days in some manure-amended soils. A rainfall simulation study found E. coli and Salmonella in runoff water from soils amended with dairy or swine manure, though pathogens were not always detected. The type of manure applied affected the levels of bacteria in runoff water.