In a review of published studies which have concerned stability of enteric viruses in surface freshwaters, those environmental variables which have been determined to have a statistically significant effect are pH, chloride, TOC, hardness, turbidity, and exposure to sunlight when in shallow trays. In the present review it was demonstrated by regression analysis that temperature was also a statistically significant factor. The rates at which inactivation of enteroviruses and rotaviruses varied in response to temperature were clearly different, with rotaviruses appearing to be much more stabile as a group in surface freshwaters. Other factors which have been cited as having demonstrable effect upon enteric virus stability in these types of waters are aerobic microorganisms, undetermined volatile or heat labile factors intrinsic to the natural water samples, nonseasonal factors intrinsic to the natural water samples, and sewage pollution in the case of at least human echovirus type 7.