随着联邦地表水处理规则（SWTR）和州SWTR的颁布，圣何塞水务公司面临着放弃或升级小型硅藻土（DE）过滤厂的决定。几个环境、设计、操作和监管方面的限制因素影响了用微滤（MF）取代现有过滤系统的决定。这是目前美国最大的饮用水MF工厂，日产量为5 mgd。自1994年2月以来，它一直在成功运作。迄今为止的结果表明，该工厂生产的成品水超过了SWTR的要求。本文介绍了新工厂的设计、施工、运行和性能要素，以及导致选择MF而非其他处理方案的因素。包括5个参考文献、表格、图表。

With the enactment of the federal Surface Water Treatment Rule (SWTR) and a state SWTR, San Jose Water Company faced a decision to either abandon or upgrade a small diatomaceous-earth (DE) filtration plant. Several environmental, design, operational, and regulatory constraints influenced the decision to replace the existing DE filtration system with microfiltration (MF). At 5 mgd this is currently the largest potable water MF plant in the United States. It has been operating successfully since February 1994. Results to date demonstrate that the plant is producing finished water that exceeds SWTR requirements. This article describes elements of the design, construction, operation, and performance of the new plant as well as factors leading to the selection of MF over other treatment options. Includes 5 references, tables, figures.