This paper discusses a study of four communities in Oregon that were divided intotwo control groups and surveyed according to water contamination problems and howtheir perceptions of risk affected their use of tap water versus bottled water. Results indicated that risk perception about drinking water appears to be affected by three factors: the consumer's level of awareness of a problem; the presence or absence of drinking water contamination problems; and, the chronicity of the problem. Findings suggest that water contamination problems contribute to increased levels of risk perception with those drinking tap water. Also, long-term problems that are not easily solved by the water utility may heighten consumers' perception of risk. Higher levels of risk perception may be the driving force behind higher rates of bottled water use in some communities. Includes 33 references, tables.