This story seems to almost be out of science fiction (or The Prisoner) but the pictures don't lie. The water people in Los Angeles are so desperate to save what water is left in some reservoirs that they are essentially putting a roof on it by filling the lakes with black plastic balls:
Facing a long-term water crisis, officials concerned with preserving a reservoir in Los Angeles hatched a plan: They would combat four years of drought with 96 million plastic balls.
On Monday, Mayor Eric Garcetti of Los Angeles arrived at the 175-acre Los Angeles Reservoir to release the final installment of the project: 20,000 small black orbs that would float atop the water. [...]
Mr. Garcetti said that the dark balls would help block sunlight and UV rays that promote algae growth, which would help keep the city's drinking water safe. Officials also said the balls would help slow the rate of evaporation, which drains the water supply of about 300 million gallons a year. The balls cost $0.36 each and are part of a $34.5 million initiative to protect the water supply.
This is an ingenious way of reducing evaporation. Perhaps the state's aqueduct system can also be filled with these balls to stop evaporation there.
HughPickens.com also submitted this article just minutes later!
(Score: 1, Funny) by Anonymous Coward on Thursday August 13 2015, @06:50AM
I almost feel bad for California. Not going to help to quell any of the conspiracy nuts about depopulation attempts though. Should probably try to sell it to Mexico for something at this point.
(Score: 3, Informative) by WillR on Thursday August 13 2015, @02:17PM
I almost feel bad for California.
Whenever you feel that coming on, remember that while they're trying to look like they're doing something by putting out more shade balls and making restaurant patrons ask twice for a glass of water, they're also still watering alfalfa fields and golf courses.
(Score: 2, Insightful) by aqui on Thursday August 13 2015, @02:57PM
( http://www.circleofblue.org/waternews/2009/world/infographic-ten-things-you-should-know-about-water/ [circleofblue.org] )
is there any reason to be surprised about this problem? BR> More than double the average European the question shouldn't be one of source conservation but one of "why do you use so much more water???" The savings potentials are real and huge. Hell many people in California didn't have water meters until recently...
Just a little bit of reading on wikipedia ( http://en.wikipedia.org/wiki/Water_in_California [wikipedia.org] ) and elsewhere on the web makes clear its a big mess due to profiteering, neglect, recklessness and stupidity (e.g. growing grass in the desert) ...
Essentially for the available water in California current practices have never been "sustainable" ( https://en.wikipedia.org/wiki/Sustainability [wikipedia.org] ) and the drought has highlighted that.
Stupidity will be punished... and profiteering even more so.
(Score: 3, Insightful) by jimshatt on Thursday August 13 2015, @06:58AM
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @07:11AM
Well, black is better at blocking and white at reflecting.
So hindering algae growth might be more important than the extra evaporation.(Extra compared to hypothetical white balls. Still better than no balls. )
(Score: 5, Interesting) by Anonymous Coward on Thursday August 13 2015, @07:13AM
White balls will break down more readily from UV exposure. The black balls contain carbon that absorbs heat but prevents breakdown. Some plastics will break down very quickly in the sun. For example, white wire ties are not UV rated while black ones are.
I suppose it's a tradeoff - more heat vs replacing the balls frequently and cleaning up the bits of degraded white plastic.
(Score: 2) by mcgrew on Thursday August 13 2015, @12:58PM
Thank you, AC, I'd been wondering the same thing.
mcgrewbooks.com mcgrew.info nooze.org
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @07:15AM
Black balls are bigger. Everybody knows that.
Haven't quite figured out how to make them both AC and DC powered .
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @12:43PM
i suppose if the blackballs are very tightly packed then "maybe" they will help with evaporation loses.
however if there are gaps then blackballs will hasten the evaporation because they become hot quicker (absorbe)
and then, because of the the gaps, a bit of wind (will happen because black surface is hotter then surrounding) will "turn" the balls, exposing the wet underside to the top air and .. voila ... evaporation and as a side effect ... cool blackballs : )
i would have gone with titanium dioxide (nano sounds cool?) painted balls ... or maybe just plain old styrofoam?
(Score: 4, Interesting) by karmawhore on Thursday August 13 2015, @02:06PM
=kw= lurkin' to please
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @07:02AM
Go the whole hog and cover entire LA with those...
This is hilarious because it's so very fucked up. More proof that people are no smarter than bacteria in a bottle.
(Score: 2) by quadrox on Thursday August 13 2015, @07:16AM
I for one do not like the idea of having even more plastic contaminating my food and water sources. How about setting up a net of ropes above the reservoir and covering it with tarp? Or basically ANYTHING else than putting plastic in the water? Seriously?
(Score: 2, Insightful) by FlyingSock on Thursday August 13 2015, @07:28AM
FIrst: You don't want no plastic in your water. You want plastic in your water.
Second: These reservoirs have a huge surface area, even if you had a tarp large enough it would still be hanging in the water (which again implies plastic in the water) same goes for a net. Gravity's a bitch like that. You could of course now propose installing pylons or something to support the tarp. But unless you invest quite a lot this would probably not be stable enough, as the water may also be quite deep and there would be significant wind stress on the tarp.
All in all I think the balls quite an elegant solution. A roof that carries itself by swimming on the surface. Of course the same solution could also have been achieved with other materials, but this would be significantly more expensive and not necessarily less harmful.
(Score: 2) by quadrox on Thursday August 13 2015, @07:37AM
FIrst[sic]: Please read my title again. I am not saying what you think I am saying.
Second: That's why you pull the ropes/net taut. As you said, tarp is probably not the ideal cover, some kind of dark cloth should do the trick though.
(Score: 2) by pogostix on Thursday August 13 2015, @08:15AM
https://en.wikipedia.org/wiki/Catenary [wikipedia.org]
pulling the ropes taut is easier said than done
(Score: 2) by jimshatt on Thursday August 13 2015, @10:48AM
(Score: 2) by Tramii on Thursday August 13 2015, @03:52PM
Plastic floating pylons?
(Score: 2) by jimshatt on Friday August 14 2015, @08:55AM
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @09:29PM
Ducks will shit into the water regardless.
(Score: 1) by chrysosphinx on Thursday August 13 2015, @07:29AM
I highly question this solution. Balls are not ideal spheres, have tiny capillary cracks on surface. Balls will move by wind. Wet half-balls effectively doubles vaporization surface from pi*r^2 to 2*pi*r^2.
(Score: 2) by FatPhil on Thursday August 13 2015, @08:10AM
I still can't get my head around the black-vs.-white logic. Absorbing heat doesn't seem the best way of slowing down evaporation.
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @09:04AM
You seem to have done your calculation with a square. But the closest packing of balls is not a square lattice, but a hexagonal one. And indeed, the balls are likely to locally form an approximation of that hexagonal lattice.
The hexagon has the area of six equilateral triangles, each having a height of r. Since for an equilateral triangle, the height is sqrt(3)/2 times the side length, and the area is half the product of side length and height, we get
Ahexagon = 6 × 1/2 × 2r/sqrt(3) × r = 2 sqrt(3) r² ≈ 3.4 r²
Clearly 2 sqrt(3) is much closer to π than 4 is.
(Score: 2) by inertnet on Thursday August 13 2015, @11:09AM
If evaporation prevention is their goal, hexagonal floating mirrors with tiny weights under the middle would work better than balls.
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @03:42PM
I think this is to control algae which is a bigger issue for them.
(Score: 2) by inertnet on Thursday August 13 2015, @08:36PM
I'm no expert, but it could be that algae actually clean the water by consuming stuff that's not supposed to be in drinking water. This solution could be worse than the problem it's solving.
(Score: 2) by mendax on Thursday August 13 2015, @07:32AM
You can't say that California doesn't have balls! We do, but the drought causes us much strife. After all, I've lost my green lawn.
As for the "gonads and strife" reference, you want to go here [youtube.com].
It's really quite a simple choice: Life, Death, or Los Angeles.
(Score: 3, Interesting) by TheLink on Thursday August 13 2015, @07:43AM
Allegedly covering the water surface with a layer of vegetable oil or vegetable oil extract can reduce evaporation by up to 75%.
The problem with the oil is wind blowing away the oil exposing the surface. Seems to me that wind would also be a problem for these balls too (if not more so - since you can still keep supplying oil upwind and collecting it downwind - whereas it's more expensive to do that for the balls).
So: Which is more toxic and harmful (to humans and animals - birds). Which reduces evaporation more. And which costs more.
http://hereandnow.wbur.org/2014/06/30/prevent-evaporation-drought [wbur.org]
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @09:14AM
If vegetable oil shares the property with fossil oil that it glues the feathers of birds, then I guess vegetable oil might be the more damaging to birds.
I'm also not sure if the fact that oil is flammable would not pose a risk. The water would not help here exactly because the oil is swimming on top of the water; that fact would also make it hard to extinguish such a fire. And of course it goes without saying that a fire on top of your lake will not exactly reduce evaporation either.
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @02:58PM
Those plastic balls could be flammable too. A thin layer of burning vegetable oil is probably less harmful and a smaller problem than millions of burning plastic balls.
(Score: 1, Interesting) by Anonymous Coward on Thursday August 13 2015, @10:03AM
Water surface is never in shadow (except at the edge). Sun's UV are lethal to most microbial life, and only specialized organisms can live on water surface. So generating shadow can lead to complete change of what organisms will live there. Probably all sun-liking microbes will die and be replaced by shadow-liking ones. Let's see what effect this will have on our health and entire ecosystem.
(Score: 5, Funny) by jimshatt on Thursday August 13 2015, @10:56AM
(Score: 2) by mcgrew on Thursday August 13 2015, @01:02PM
They discussed that on CBS news. The balls prevent algae from growing, and algae releases toxins.
mcgrewbooks.com mcgrew.info nooze.org
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @11:35AM
What does this have to do with The Prisoner? Here you are putting lots of little plastic balls to float on the water to reduce evaporation. In the TV show you have a giant ball made of some rubbery but unspecified material that is a security device. How the hell are these two things related?
Just a sad, pathetic attempt at pulling in a cool cultural reference to try to appear "cool".
(Score: 0) by Anonymous Coward on Thursday August 13 2015, @03:15PM
Both are spherical and artificial.
Be thankful he didn't invoke the death star. It's also spherical and artificial. It's even related to evaporation. It did, however, not reduce evaporation, quite the contrary: It evaporated a whole planet.
(Score: 2) by MrGuy on Thursday August 13 2015, @01:29PM
Los Angeles has been doing this since 2008. [latimes.com] Well before the current drought concerns.
This isn't a new idea or some out-of-the-box visionary plan. This is extending an idea from the past with some track record of success to other areas.
(Score: 2) by Anne Nonymous on Thursday August 13 2015, @01:30PM
Now there will be plenty of water to put on lawns and golf courses and to wash our cars once a week.
(Score: 2) by Joe Desertrat on Thursday August 13 2015, @05:38PM
Don't forget filling your swimming pool!
(Score: 2) by morgauxo on Thursday August 13 2015, @07:01PM
I'm thinking they could go with a hockey puck shape with a reflective surface. The flat top means that most of the energy would be reflected upwards, not back into the water. Or.. better yet, weighted hockey puck so that the same side is always up. Make the bottom and sides black but the top reflective.
Of course.. in such quantities.. that would likely be far too expensive. Might as well consider building a dome at that point.