 This approach generally results in lower levels if "E. coli" being used as a standard or “benchmark” based on a study that indicated pathogens were detected in 80% of water samples with less than 100 cfu "E. coli" per 100 mL.Most cases of bacterial gastroenteritis are caused by food-borne enteric microorganisms, such as "Salmonella" and "Campylobacter"; however, it is also important to understand the risk of exposure to pathogens via recreational waters.This is especially the case in watersheds where human or animal wastes are discharged to streams and downstream waters are used for swimming or other recreational activities.