Why Are 96,000,000 Black Balls on This Reservoir?

May 10, 2019 by 45 Comments

I took a boat through 96 million black plastic balls on the Los Angeles reservoir to find out why they’re there. The first time I heard about shade balls the claim was they reduce evaporation. But it turns out this isn’t the reason they were introduced.

Huge thanks to LADWP for arranging this special tour for me. Next time let’s put the GoPro on the submersible!

The balls are made of high density polyethylene (HDPE) which is less dense than water so they float on the surface of the reservoir even if they break apart. They are 10cm (4 inches) in diameter and contain about 210ml of water. So the main reason they are on the reservoir is to block sunlight from entering the water and triggering a chemical reaction that turns harmless bromide into carcinogenic bromate. This effect occurs with prolonged exposure to bromate so regulators insist that levels be kept below 10 microgram per liter on average over a 12 month period.

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme and everyone who provided feedback on an early draft of this video.

Thanks to:
Las Virgenes Reservoir for footage of initial shade ball dump
Euro-Matic for bird into jet-engine footage

Researched and Produced by Casey Rentz

Animations by Maria Raykova

Music from http://epidemicsound.com “Colorful Animation 4” “Seaweed”

And from Kevin MacLeod “Marty Gots a Plan”

This is an educational video about the science of water quality.


45 Replies to “Why Are 96,000,000 Black Balls on This Reservoir?”

  1. Djo Buff says:

    Because 48000000 African American men are standing on their heads under the water? No racism intented thats just a lot of black balls

  2. IR IR says:

    Die Tatsache, dass einige Millionen in Deutschland den Grund dafür kennen, ist traurig genug!😥😥😥😥😥🤔🤔🤔

  3. maxio danish says:

    Down here in India, We have a legend tried to cover the dam with Thermocol sheets..!

  4. Nick Bosman says:

    Huh huhuhhuh. He said "balls". Huh huh. Wait the other dude said "balls" too. Huh wait … what? Huh huh huh

  5. Why are they black? Shouldn't they be white

    To prevent heating the water more

  6. Liader Yang says:

    @5:53 a bird got sucked in the engine. 😂😂😂😂

  7. Timothy J says:

    California – Bans straws

    Also California –

  8. This is discusting! 🤢 glad i dont live there.

  9. 外国人って金持ちの上に暇人だなww

  10. “I had so many Questions like Why are they Black?”

    Trust me bro I’ve heard that Question before.

  11. "Its very rare to see 96 million of anything"

    Grass: Am I A Joke To You?

  12. David Strong says:

    How much micro plastics do they put in the water?

  13. "Very rare to see 96 million of anything"
    Atom: helo

  14. Laura Oguttu says:

    "Is it hard to drive on the black balls"? -..even a two year old can answer this question!!…smh

  15. street wise says:

    In order to understand whole video!o have to be a scientific expert!I passed.

  16. Here from the burnout video.

  17. Zesteria says:


  18. And then there is legend "Sellur Raju"

  19. Probability in real life would look like this

  20. Amtul Baseer says:

    What about the fish?

  21. Friction, friction =micro plastic?

  22. Why don't you use crude oil? 😉

  23. D TRI says:

    can we get this to 96,000,000 views ?

  24. Kim kardashian has entered the chat

  25. Kolos Varga says:

    Who else seen it, at 5:51 a bird flu into to the jet engine?

  26. 中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!中华人民共和国万岁!

  27. Ollie Bri says:

    Bromate- is it the same meds they give soldiers to stop erection?

  28. dan75robot says:

    how the us government tries to cover up mass murder of every american probably after taking a VACCINE!

  29. Bro I heard That "What?" at 0:25 and I swear I thought someone was behind, while I was lying in my bed

  30. Onder Ozenc says:

    I wonder why not white reflector balls ?

  31. Mario Jam says:

    Each one for a subscriber of Pewdiepie. Wait, that's not enough!

  32. shakaib khan says:

    This guy made me lay down and listen to him talk about black balls on a lake for 12 minutes. He gets my sub

  33. Beni Black says:

    48 million lost something 👻🐀

  34. DBK LMJ says:

    The environmentalist morons should have a a hay day with with. They are plastic! Good lord ppl are hypocrites

  35. That's a lot of balls

  36. H A says:

    You should have dived in water and seen from down below.

  37. Why they don’t use plants?

  38. Would the LA reservoir staff ever consider travel by fan boat?

  39. UNIPIXEL says:

    they look like caviar, yes i'm hungry, no i'm not craving caviar

  40. I think that looks good now but at some point the plastic will start degrading into the water, and guess what you'll be drinking! I think I will start collecting rainwater lol

Leave a Comment

Your email address will not be published. Required fields are marked *