LOS ANGELES — It wasn't an accident or a mistake: The Los Angeles Department of Water and Power (DWP) dropped 400,000 floating plastic balls into the Ivanhoe Reservoir on June 9 to protect drinking water there, according to a June 10 article in the Los Angeles Times.
The reservoir water must be shaded to prevent sunlight from mixing with bromine and chlorine present in the water, according to the article. This trio causes the formation of bromate, a carcinogen.
“Water quality doesn’t get any more exciting than this,” DWP biologist Marina J.F. Busatto said in the article.
According to the article, elevated levels of bromate were first discovered in Ivanhoe and neighboring reservoirs between June and October 2007. The balls were chosen to shade the reservoir because a tarp would have been too expensive and a metal cover would have taken too long to install, especially during a drought year.
The 102-year-old facility serves about 600,000 customers in downtown and south Los Angeles. Ivanhoe and neighboring reservoir Elysian will be covered by 3 million balls each for the next four years, according to the article.
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