A northern California treatment plant installed microfiltration to satisfy design constraints and comply with SWTR requirements. 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 diatomaceousearth (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.

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Aims To evaluate a low‐cost water quality test for at‐scale drinking water safety estimation in rural India. Methods and Results Within a longitudinal study to characterize variability in household drinking water safety in rural Maharashtra, we piloted a low‐cost presence–absence (LCPA) microbial test designed to be used by volunteer residents in rural areas. In comparing the LCPA results with standard laboratory methods for enumeration of Escherichia coli, we found that LCPA tests using modified mTec media were highly sensitive in detecting drinking water of moderate risk (88% of tests were positive at E. coli counts of 11–100 CFU per 100 ml) and high risk (96% of tests were positive at E. coli counts of 101 + CFU per 100 ml). The LCPA tests demonstrated low specificity for E. coli specifically, due to concurrent detection of Klebsiella: 38% of LCPA tests were positive even when E. coli was not detected in a 100 ml sample by membrane filtration, suggesting the test would be conservative in risk estimation. We also found that 47% of participants in rural villages in India were willing to conduct tests and return results after a brief training, with 45% of active participants sending their water testing results via short message service. Conclusions Given their low cost (~US$0.50 as piloted) and open‐source format, such tests may provide a compelling alternative to standard methods for rapid water quality assessments, especially in resource‐limited settings. Significance and Impact of the Study The lack of availability of water quality data constrains efforts to monitor, evaluate and improve the safety of water and sanitation infrastructure in underserved settings. Current water testing methods are not scalable because of laboratory and cost constraints. Our findings indicate the LCPA or similar low‐cost microbial tests could be useful in rapid water safety estimation, including via crowdsourcing.

Public educationWhen the salesman in the doctor's smock knocked on the door of the MWD employee, he got more than he bargained for. The employee happened to be a supervising chemist working for MWD's water quality branch. Holding back a JOURNAL AWWA Jose Water Company, hesp&zt six years at the East Bay Municipal Utility District (Oakland, Calif.) directing water quality control and regulatory compliance programs. A recipient of the 1987 OPFLOW Publications Award, he has written and produced public education materials on drinking water quality. Yoo chaired two task groups for the sixteenth edition of Standard Methods. He has bachelor's, master's, and PhD degrees from the University of California, Davis.JOURNAL AWWA

The San Jose Water Co.'s annual water quality report is the cornerstone of the utility's public education program. The report, created in response to news reports about the quality of groundwater in Silicon Valley, attempts to “set the record straight” regarding the quality of water delivered to customers. The report, a bill stuffer, is sent to all customers. It describes water supply sources, treatment processes, and water quality control programs; it also includes a table comparing local water quality with state and federal drinking water standards. The author conducted an informal survey of industry practices concerning water quality reports. All respondents provide some type of water quality data for customers on request, but only 3 percent of regularly distribute such reports to all customers.