Utility Committee Agenda and Packet 2020 05 12

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it under emergency conditions. The emergency interconnect, 200 feet of pipe and a couple of valves, ties the potable distribution line into the backwash influent line to let operators backwash filters using distribution system water and pressure. This provides a backup system so filters can be washed quickly and put back into service without damaging the media or potentially violating regulations. BETTER SOURCE WATER Data-driven decisions also helped at the Louisville Reservoir, one of three raw water reservoirs in the sys- tem. For about a decade, the reser- voir had problems with algae blooms that led to taste and odor issues and widespread complaints from customers. “It was a pretty serious issue,” Venette says. “We bought new lab equipment including a Leica micro- scope, Vortex Mixer (Thermo Fisher Scientific), and centrifuge (Thermo Fisher Scientific) and implemented new testing procedures to better ana- lyze and measure algae in our source water. Operator Thoa Pham became absolutely dedicated to and excels at understanding algae in the lab.” She provides data that helps operators stay ahead of algae blooms. The operators learned to iden- tify the algae species so they could see the blooms coming. “We looked at algae data for the past 10 years,” Venette says. “We found we could have higher levels of some and it wouldn’t affect taste and odor, but the blue-green algae is what kills us. It causes the most issues.” Analysis showed that the blue- green algae arrived mostly through one specific supply line. Team mem- bers decided to tackle that problem in-house because of their knowledge of the system. “We began a new pro- tocol using copper sulfate, an algae- cide, to surface-treat our reservoir from a boat. And we added an in- line injection system that our oper- ators designed and installed to treat our incoming water with copper sulfate.” HUMAN INSTRUMENTS The staff also began using bar- ley straw to control algae in the res- ervoir intake. The results were good. Venette, who holds Class A water, wastewater and industrial wastewa- ter licenses in addition to Grade 4 collection and distribution licenses, says the use of barley straw was based on experience he had in a previous job where he used it in a wastewater lagoon to knock down ammonia and provide nitrification: “We buy it from a local farm and replace it every cou- ple of weeks.” ‘‘We bought new lab equipment ... and implemented new testing procedures to better analyze and measure algae in our source water.” GREG VENETTE Jeff Owens, operator, collects a filtered water sample. Plant operators who live in the city have been enlisted as early- warning taste and odor monitors. Operator Steven Daniels monitors the plant’s variable-frequency drives (Eaton). Prerelease Version – NOT FOR REPRODUCTION 33