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Plastic ‘shade balls’: The hypnotizing tool California is using to save water

"Shade balls away!" Los Angeles Mayor Eric Garcetti announced the completion of the "shade ball" project, wherein balls were released into the L.A. Reservoir in an effort to slow evaporation. (Video: The Washington Post)
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California is experiencing one of its most severe droughts on record, and its local municipalities have an astounding strategy to save water: turn their reservoirs into massive, floating ball pits.

During the past couple years, cities across the state have dumped millions of “shade balls” — black, plastic balls weighted down with water — into their reservoirs.

The result is a terrifyingly hypnotic scene: a barreling barrage of black balls that just never seems to end.

The tactic prevents the chlorine in the water (used to disinfect it from pathogens) from reacting with sunlight to become bromate, a suspected carcinogen. It also protects water sources from wildlife and blocks it from the sun to reduce evaporation.

[California’s rural poor hit hardest as massive drought makes remaining water toxic]

Los Angeles officials estimated at a news conference that shade balls will save somewhere around 300 million gallons of water each year. Of course, that’s nothing compared with the 13.6 billion gallons of water consumed by Los Angeles in June of this year alone.

“This is a blend of how engineering really meets common sense,” Marcie Edwards, general manager of the Los Angeles Department of Water and Power, said at the news conference Tuesday, according to ABC 7. “We saved a lot of money, we did all the right things.”

Las Virgenes Municipal Water District releases new shade balls "to improve the quality of recycled water stored in the reservoir." (Video: Las Virgenes Municipal Water District)

The Environmental Protection Agency has mandated that all reservoirs be covered, and in Los Angeles, that would have cost an estimated $300 million to cover the 175-acre facility, ABC 7 reported. But thanks to shade balls, the bill was cut down to just $34.5 million.

Aside from Los Angeles, shade balls have also been used in the City of Ivanhoe and the Las Virgenes Water District in Southern California.

They can also be recycled, and are expected to last as long as 10 years.

Way to go, shade balls.

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