4 ms·
Why Are 96M Black Balls on This Reservoir?
- relbeek2 7y agoThey are called shade balls, they are used to reduce evaporation by up to 90%.
- godman_8 7y agoI can tell you didn't watch the video
- vmh1928 7y agoor even read the description below the video.
- jandrese 7y agoThe 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.
- beautifulfreak 7y agoBromide 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
- javagram 7y agoThis 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-ecological-costs-of-plastics-in-water/ https://discardstudies.com/2015/08/16/las-shade-balls-the-ec... 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?
- kyriakos 7y agoThe guy sounds very positive that they are safe. Too positive if you ask me.
- dTal 7y agoThat 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?
- kyriakos 7y agoConsidering 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.
- NullPrefix 7y agoThey 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.