东湾市政公用事业区（EBMUD）的胡桃溪和拉法叶在线过滤厂处理来自内华达山脉的高质量Mokelumne河水。与直接过滤相比，在线过滤不包括絮凝步骤，加州SWTR认为在线过滤是一种替代处理技术。使用替代治疗技术的设施必须向州政府证明，它们能够分别满足贾第虫囊肿和病毒的2-log和1-log清除要求。加利福尼亚州SWTR表示，这可以通过证明设施能够可靠地生产满足过滤和消毒性能要求的水来实现，最近12个月的运行数据表明了这一点。1992年期间，这两个设施均达到了SWTR过滤和消毒性能要求，并分别获得了2-log和1-log的贾第虫和病毒清除积分。 EBMUD希望确定这两个设施是否可以通过颗粒计数示范研究获得额外的贾第鞭毛虫囊肿切除学分。两年前，奥林达过滤厂（Orinda filter plant）进行了颗粒计数示范研究，这是第三家处理同一水源的EBMUD在线过滤厂。这些研究确定，Orinda植物可以达到2.7对数去除贾第虫囊肿大小范围内的颗粒。

The East Bay Municipal Utility District's (EBMUD) Walnut Creek and Lafayette in-line filtration plants treat high quality Mokelumne River water from the Sierra Nevadas. In-line filtration, in comparison to direct filtration, does not include a flocculation step and is considered by the California SWTR to be an alternative treatment technology. Facilities using alternative treatment technologies must demonstrate to the state that they are able to meet the 2-log and 1-log removal requirements for Giardia cysts and viruses, respectively. The California SWTR states that this can be done by demonstrating that the facilities can be operated to reliably produce water meeting the performance requirements for filtration and disinfection, as demonstrated by the latest 12 months of operating data. The SWTR filtration and disinfection performance requirements were met by both facilities during 1992 and Giardia and virus removal credits of 2-log and 1-log, respectively, were received. EBMUD desired to determine if the two facilities could obtain additional Giardia-cyst removal credits through particle count demonstration studies. Two years previous, particle count demonstration studies were performed at the Orinda filter plant, a third EBMUD in-line filtration plant treating the same water source. These studies determined that the Orinda plant could achieve a 2.7-log removal of particles in the Giardia-cyst range size.