October 8, 2011

Ivanhoe Reservoir, Los Angeles

Photograph by Gerd Ludwig, National Geographic

This Month in Photo of the Day: Photos From New National Geographic Books

In 2007, high levels of bromate—a carcinogen formed when bromide and chlorine react with sunlight—were found in Los Angeles’s Ivanhoe Reservoir. Today three million black plastic balls help deflect UV rays.

(From the upcoming National Geographic book Visions of Earth)

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Ricardo Kutz
Ricardo Kutz

@sebestyen tiberiu Your mirror idea would be too expensive, each of those balls cost 40 cents, at 6.5 million balls for both Ivanhoe and Elysium that's 2.6 Million. Ivanhoe and Elysian reservoirs will be blanketed by about 3 million balls each for about four years. They will be removed when a covered replacement reservoir is built near Griffith Park's Travel Town area.

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