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LA is dumping millions of plastic balls into its reservoir to tackle the drought

sciencealert.com

1–10 of 78 posts

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#3
They're not dumping plastic balls in order to tackle the drought, they're being dumped because the EPA mandated that all reservoirs be covered. Direct sunlight will cause bromide and chlorine in the water to mix into bromate, a known carcinogen, and the EPA wants to prevent buildup of this compound in the drinking water supply. Covering the reservoir with a tarp is too expensive (costing over $300 million) and plastic balls are a much cheaper option. The evaporation reduction is a secondary benefit, not the primary one, and the article title should reflect this.

There's much better coverage of this story here [1] and here [2].

[1] http://www.npr.org/sections/thetwo-way/2015/08/11/431670483/...

[2] http://news.nationalgeographic.com/2015/08/150812-shade-ball...

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#5
post #2

"in which a total of 96 million balls have been poured" "they're cheap (costing just 36 cents per unit)" Is that really cheap, or is it just because it's in LA?

Depends on the ball ... you need to use food grade plastic. And certifications and on and on and on ...

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#7
post #2

"in which a total of 96 million balls have been poured" "they're cheap (costing just 36 cents per unit)" Is that really cheap, or is it just because it's in LA?

As sibling poster [1] mentioned, the balls are cheaper (and probably last longer) than the tarp alternative.

[1] https://news.ycombinator.com/item?id=10052777

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#8
What I don't understand is that they dumped black balls in the reservoir. If you want to keep the water cool to lessen evaporation wouldn't it make sense to use white or reflecting balls so the water stays slightly cooler?

I would be glad to know why black balls are chosen.

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#9
post #3

They're not dumping plastic balls in order to tackle the drought, they're being dumped because the EPA mandated that all reservoirs be covered. Direct sunlight will cause bromide and chlorine in the water to mix into bromate, a known carcinogen, and the EPA wants to prevent buildup of this compound in the drinking water supply. Covering the reservoir with a tarp is too expensive (costing over $300 million) and plasti…

doesn't the plastic + sunlight + heat combination release dangerous chemicals in the water?

also, why are they black, doesn't that attract more heat?

Re: LA is dumping millions of plastic balls into its reservoir to tackle the drought

#10
Do they really need to invent that much? It's true that the current situation is maybe the worst they ever faced. But there are a lot of places where water is even more valuable as a resource. Are they also looking into what people in the desert do to keep their water sources alive, etc?
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