区域气候变化和变异性及其对水资源的影响还没有得到太多的研究。气候预测表明，风暴强度将更大，平均降水量可能更大。降雨和径流与粪口病原体引起的水传播疾病的个别暴发有关。对美国2105个流域1971年至1994年的水传播疾病暴发数据进行了地下水和地表水分析。20%到40%的疫情与极端降水有关。这种与极端降水的关系在地表水和地下水中都具有统计学意义，尽管在地表水暴发时更为明显。 作者提出了改进水质变化评估的建议，以及气候变化和环境因素对水传播疾病风险的影响。包括34个参考文献、表格、图表。

Regional climate change and variability and their effect on water resourceshave not been the subject of much study. Climate predictions suggest that storms will be of greater intensity and that the average precipitation event is likely to be heavier. Rainfall and runoff have been associated with individual outbreaks of waterborne disease caused by fecal-oral pathogens. Waterborne disease outbreak data from 1971 through 1994 were analyzed for groundwater and surface water in 2,105 US watersheds. Between 20 and 40 percent of outbreaks were associated with extreme precipitation. This relationship with extreme precipitation was found to be statistically significant for both surface water and groundwater, although it was more apparent with surface water outbreaks. The authors offer recommendations for improving the assessment of changes in water quality and the effect that climate variability and environmental factors have on waterborne disease risk. Includes 34 references, tables, figures.