The drinking water served by the SFPUC is among the best in the country. During these stressful times, customers do not need to worry about their tap water. The SFPUC employs a multi-step treatment process that removes and kills viruses, including coronaviruses such as COVID-19, as well as bacteria and other pathogens. The SFPUC’s treatment plants use several disinfectants, including ultraviolet light, chlorine, and ozone, to provide 10 to 60 times the required level of treatment for viruses. There is no need to buy bottled water, boil tap water or purchase home treatment for tap water during this shelter-in-place. The reason for this certainty is because of the hard working staff at the SFPUC’s Water Quality Division.
A previous story already highlighted the work of Water Quality Engineers who monitor water quality and work with the SFPUC’s operators on treatment processes. The eyes and ears of water quality – the Environmental and Field Services Sections – take the samples throughout the system.
The Water Quality Division has seven laboratories located throughout the SFPUC’s regional water system, from Moccasin to Treasure Island. Four laboratories support drinking water operations and three laboratories support wastewater operations. Today let’s focus on what happens to the samples after Field Services collects them. Meet some of the Water Quality Laboratory Services staff.
“We are here at the Lab no matter what happens, 365 days a year. We make sure your water is safe to drink. We must still meet the State’s regulatory requirements,” says Laboratory Services Manager Megan Tran.
On an average day four supervisors, six chemists, six biologists, and four technicians process the daily samples taken by field staff. The Millbrae Lab also receives and analyzes samples for 10 of the SFPUC’s Wholesale Customers as well as the agency’s own distribution and the regional systems.
Field Services staff brings water samples to the Millbrae Lab. A Lab technician receives the samples. The technician checks the cooler for proper temperature, verifies there are no discrepancies between each sample container and the chain of custody then confirms the location of each test. Field Services can only relinquish the samples once a Millbrae Lab Technicians signs for them and takes formal custody.
Once the sample formally enters the Lab, each specialty group receives the sample to test it. Chemists look at the water chemistry to ensure that the water falls within the state-mandated regulatory levels for pH, fluoride, and residual disinfectant. The residual disinfectant prevents the spread of waterborne diseases such as cholera, dysentery, and typhoid. It kills pathogens and viruses, like the coronavirus. Biologists test for total coliform in the water. Once the sample has been fully tested, the results are peer reviewed, and released for further review and analysis by the Water Quality Engineers and to report to the State.
During the current COVID-19 emergency, people who work at the laboratory must still report to work as usual. They have moved equipment around the lab so people are working on opposite sides of the lab to maintain social distancing. Lab staff ensure only one designated person works on a piece of equipment at a time. Safety is paramount in the laboratory; staff wears appropriate personal protective equipment (gloves, safety glasses/goggles, and other safety equipment) when working in the lab as always.
To ensure continuity of laboratory operations during the COVID-19 emergency, specialty groups are divided into two teams. Each team is working/telecommuting on an alternate weekly schedule. While one team is analyzing samples in the lab, the second team is telecommuting keeping up with training and catching up on documentation. In the unlikely event that one team must be isolated; the second team will continue to test samples ensuring the water is safe to drink.
“We take our water testing very seriously. Even during this crisis, we still have to meet our reporting deadlines,” says Tran. “I feel my staff does an excellent job. Even on holidays or during a shelter in place, we still have the expectation of excellent performance to test our water on behalf of our customers.”