
Why Are 96M Black Balls on This Reservoir? - akudha
https://www.youtube.com/watch?time_continue=723&v=uxPdPpi5W4o
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javagram
This seems like a solution to the bromate problem that in a decade or two will
be looked back upon as a mistake as the balls deteriorate and leak plastics
into the drinking water? [https://discardstudies.com/2015/08/16/las-shade-
balls-the-ec...](https://discardstudies.com/2015/08/16/las-shade-balls-the-
ecological-costs-of-plastics-in-water/)

Are there alternatives, like filtering and chlorinating the water on-demand
rather than pretreatment and storing in a giant open air reservoir that then
needs a bandaid fix like this?

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dTal
That question occurred to me too. They say they last 10 years? Fantastic,
that's very reasonable. What happens then? They dredge them all back out of
the water and replace them? Because that sounds like a hell of a logistical
problem compared to dumping them in.

Your link, however, appears to persist in the misconception that their purpose
is to prevent evaporation. Why is it such a common meme?

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kyriakos
Considering their original cost taking them out of the lake shouldn't
comparatively cost a lot. They are all at the surface and can be pushed to the
shore and collected.

The bigger problem is that they will start deteriorating and leaking plastic
long before their 10 year life time. After all its plastic in under uv light
and constantly changing temperature.

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NullPrefix
They keep drinking water in the open air? What did they used to do about birds
shitting in it? Even now, some birds can shit on those balls and the drinking
water will wash it.

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relbeek2
They are called shade balls, they are used to reduce evaporation by up to 90%.

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jandrese
The video explains that the evaporation reduction was a side effect. The real
reason is to reduce the level of cancerous Bromide down to safe levels, which
could only reasonably be achieved by blocking sunlight from the water.

They tried a bunch of ideas for blocking the sun and settled on the balls as
the best compromise between cost, effectiveness, and safety.

There are a couple of other benefits. They need far less chlorine to manage
algae growth and it discourages waterfowl from taking up residence in the
pool, also increasing water quality. They expect the balls to pay for about
half of their cost over an expected 10 year lifetime from the savings in
chlorine and evaporation.

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beautifulfreak
Bromide is the safe form. Bromate is the carcinogen, a side effect of sunlight
and chlorination, but it also forms if ozone is used to sterilize the water.
[https://en.wikipedia.org/wiki/Bromate](https://en.wikipedia.org/wiki/Bromate)

