滑铁卢自治区位于加拿大安大略省多伦多以西约50英里处。该地区负责三大城市中心的供水:滑铁卢、基奇纳和剑桥。直到1992年，一个地表水供水系统从格兰德河开始运行，该地区的总人口由126口水井供水。1993年春，该市市中心爆发了隐孢子虫病，确诊病例超过200例。本文描述了疫情爆发前发生的事件以及随后采取的行动。本文描述了以下内容:区域供水系统、疫情爆发、对问题的反应、调查结果和短期建议、电厂绩效审查、电厂启动和恢复供水、长期优化以及1994年的运营指南。作者发现，在疫情暴发时，水处理厂运行良好，符合所有监管水质标准。 他们得出结论，根据目前的规定，几乎任何植物都容易受到隐孢子虫病暴发的影响。

The Regional Municipality of Waterloo is located approximately 50 miles west of Toronto, Ontario, Canada. The region is responsible for water supply to three large urban centers: Waterloo, Kitchener, and Cambridge. Until 1992 when a surface water supply system was brought on line from the Grand River, the total population of the region was supplied by 126 wells. In the spring of 1993, the urban centers of the municipality experienced an outbreak of cryptosporidiosis with over 200 confirmed cases. This paper describes the events which took place before the outbreak and the actions which followed. The paper describes the following: the regional water supply system, the onset of the outbreak, response to the problem, findings and short term recommendations, plant performance review, plant startup and resumption of supply, long term optimization, and 1994 operational guidelines. The authors found that the water treatment plant was operating well at the time of the outbreak and met all regulatory water quality criteria. They conclude that almost any plant would be vulnerable to an outbreak of cryptosporidiosis under the current regulations.