Shade balls on reservoirs in LA

[splitwdw]

Maybe this should be posted under "funny joke Thursday".
I was reading about the shade balls that they are using on reservoirs in California to help stop evaporation. The balls also have some kind of UV coating to keep the sun from penetrating through the covering and growing algae. These balls are black and partially filled with water so they don't blow around. Wouldn't the balls heat up and heat the water underneath and cause more evaporation not less? I'm thinking about my black truck with dark leather interior and what it feels like after sitting in the sun.
Just heard on the news that it cost 34.5 million and the balls have a life of 10 years.
http://www.nytimes.com/2015/08/13/u...hade-balls-combat-a-nagging-drought.html?_r=0

 

[RunningBum]

Another article says it will work and is a lot cheaper than the original $300M plan to cover the reservoir.

Los Angeles Reservoir Covered With 96 Million Shade Balls to Conserve Water Amidst Drought - ABC News

 

[marko]

The title of this thread had me thinking that this was about proper sunscreen techniques while on LA's reservoirs.
Once again, wrong!

 

[pb4uski]

While I think it is an interesting idea, I would have thought that the balls woudl be white to reflect light rather than black to absorb light for the same reason that people in hot climates tend to prefer white cars.

 

[GrayHare]

I was surprised by the black color and wondered about it too. I'd expect those balls to have less albedo than water, thus heat the top of the lake and increase rather than decrease evaporation.

 

[marko]

I was surprised by the black color and wondered about it too. I'd expect those balls to have less albedo than water, thus heat the top of the lake and increase rather than decrease evaporation.

Also, don't you want to have sunlight get to the water in order to provide some sort of disinfectant (not sure I"m saying it right) property?

I'd think that water covered up like that would get full of bacteria etc like a hot tub without chemicals.

 

[Lakewood90712]

I am extremely well acquainted with The LA DWP. If there is a way to piss away money . it will be done.

 

[M Paquette]

This covering is for the reservoirs holding treated water. Sunlight will trigger a reaction between added chlorine and any organic materials to form chloramine compounds, which are not good things to drink. The requirement to cover treated water reservoirs is there specifically to limit production of these compounds. This is also why the material is black.

Most communities hold treated water in tanks, on hilltops or in the flatlands, downtown with the city name painted tastefully on a tank at the top of a tower. ;-)


Sent from my iPad using Early Retirement Forum

 

[Redbugdave]

This covering is for the reservoirs holding treated water. Sunlight will trigger a reaction between added chlorine and any organic materials to form chloramine compounds, which are not good things to drink. The requirement to cover treated water reservoirs is there specifically to limit production of these compounds. This is also why the material is black.

That's very interesting Paquette. I do know up north they have spread coal dust over the snow to absorb heat and melt rivers faster, etc.