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The L.A Reservoir has 96 million black balls floating on it. When the shade balls were introduced into the reservoir, many people had questions about the purpose and effectiveness. The most common answer is to reduce evaporation during summer months. The correct answer is much more in depth, although evaporation reduction is a positive outcome.

Bromide is a naturally occurring substance that is harmless on its own and nearly impossible to remove through filtration. When Bromide comes into contact with chlorine under sunlight, Bromate is created. Bromate is a carcinogenic that is toxic to humans. After many studies, the Los Angeles Department of Water and Power found that shade balls have the ability to stop sunlight from reaching water and stopping the reaction that creates Bromate in an economical and simple way.

The shape of the balls allows them to rise and fall with the water level along with the added benefit of reducing algae growth. The balls additionally slow evaporation down by 80%-90% and save money on the use of chlorine, covering the costs of half the balls. When the balls have reached the end of their life in 10 years, the balls have a plastic salvage value that additionally helps to recover costs.

Written by Justin Stanphill