Zone 7 Water Agency is now treating its water supply with ozone, replacing chlorine as the main disinfecting treatment and "enhancing quality of finished water" for customers, officials announced on Tuesday.
The agency's mostly completed $49 million ozonation project is now up and running at the Del Valle Water Treatment Plant in Livermore, which has been upgraded in recent years to make use of ozone as a powerful water disinfectant.
The bond-funded treatment system is part of Zone 7's capital improvement plan, and will treat an estimated 40 million gallons per day (mgd) of production capacity.
Algal blooms "are among the challenges" that Zone 7 said they are faced with treating the agency's raw water supply. Blooms are normal, but officials said "they are becoming more frequent." Besides causing taste and odor problems, the algae also makes it more difficult to treat the water
In a statement, officials said ozonation is "the latest investment by Zone 7 to make the treatment process more efficient and improve water quality to better serve the community."
Board President Olivia Sanwong said the investment in "best-in-class technology" demonstrates the agency's commitment to high-quality water.
"Ozonation is a proven, successful treatment method that will improve our water, making it cleaner, safer and better tasting -- straight from the tap," Sanwong said.
Ozone was chosen to replace chlorine as Zone 7's main disinfectant over multiple other options because it makes the water treatment process more efficient and improves water quality "by treating taste and odor impacts from algae growth, reducing chlorine-related byproducts, and killing even more pathogens than chlorine."
Zone 7 said that ozone is also "the technology of choice for treating other contaminants of emerging concern, such as cyanotoxins produced by blue-green algae, endocrine disruptors and pharmaceuticals that can make their way into raw water supplies."
The Patterson Pass Water Treatment Plant is also investing in ozonation, and expected to go online with the system in 2022.