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

  • Published on May 10, 2019
  • 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 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.

Comments • 61 603

  • Daniel Charles Cook
    Daniel Charles Cook 2 hours ago

    The new Song by Daniel Charles Cook on Spotify👉open.spotify.com/album/5UVibrWxbWgdenj77LFzXV?si=e-0ItBRWTAiDuUYPVqtbmg

  • SimoExMachina2
    SimoExMachina2 4 hours ago

    Quentin Tarantino could have a new idea for a film here: Reservoir Balls.

  • Elena Vasiljeva
    Elena Vasiljeva 4 hours ago

    For how long the shade balls are gonna last (years)? Will the workers remove them all and pour new ones? Maybe i missed that answer in video..

  • I eat nuggets
    I eat nuggets 13 hours ago

    "Like why are they black"

  • Aussie Asian
    Aussie Asian 15 hours ago

    Imma go ahead and take a few

  • Raymond Ross
    Raymond Ross 20 hours ago

    How will COPPA affect this? As a nine year old I would have jumped to watch this video. Veritasium, what are your thoughts?

  • S L
    S L 21 hour ago

    Could have done floating solar with the all the same benefits plus generates electricity AND you don't have 96 million plastic balls to dispose of.

  • Sumi S
    Sumi S Day ago

    Things humans do to amuse themselves!

  • Sebastian Cadden


  • David Hrecarte
    David Hrecarte 2 days ago

    Alguien vio que la turbina del avión succionó una AVE 😱😨

  • 100.000 Subscribers With Videos

    ✨Who wants to help eachother get 1k✨

  • Xero Punt
    Xero Punt 2 days ago

    why of course! the neglected part of BBC

  • Arjun R
    Arjun R 2 days ago +1

    How will you retrieve these 96millions balls from river after season change?

  • Fortnite Outlaws
    Fortnite Outlaws 2 days ago +1

    I love how people say we drink out of this and their driving a GAS BOAT in it

  • amber gentry
    amber gentry 3 days ago

    Sounds like a good time to me

  • Himaja Challa
    Himaja Challa 3 days ago

    Did they remove them?

  • David Beruashvili
    David Beruashvili 4 days ago +2

    someone made a lot of money with his balls :D

  • KingCarrot Cake
    KingCarrot Cake 4 days ago

    Veritasium:Why are they black???

  • Yveltr
    Yveltr 4 days ago

    5:52 my pencil when I put it in the sharpener

  • the King of Cheddar Cheese

    5:51 am I the only one that almost punch the device when the bird went into the jet engine

  • MobileMusic
    MobileMusic 4 days ago

    *5:50** a bird gets into the aircraft turbine and gets out probably dead!*

  • Patrik VV.
    Patrik VV. 4 days ago

    What happens after 10 years?

  • Fredrickson the 96th

    Jesus Christ... that poor bird!

    EXILE MEDIA 5 days ago

    I didn’t know nature can loiter in nature lol.. I guess my human a$ is loitering in my house watching this... 🤔

  • Felhek Lehrian
    Felhek Lehrian 5 days ago

    23k dislikes

  • Hot Cheetos
    Hot Cheetos 5 days ago +9

    The Reservoir: "You can eat shadeballs"
    Eating Challenge TVcliprs: Are you challenging me?

  • D4RK-Th3 B0T B0t
    D4RK-Th3 B0T B0t 5 days ago

    I read this in a magazine after a class test

  • Keneth García
    Keneth García 6 days ago


  • Tahir Khan
    Tahir Khan 6 days ago

    Don't know y i am watching this video on 2am ? with a accounting book in one hand and mobile in other.

  • よーでるよーでる

    unbalance water?

  • Xrobo12
    Xrobo12 6 days ago

    5:52 poor bird

  • Ms. Lazy
    Ms. Lazy 6 days ago

    Was it just me or did someone see that bird in 5:53 get sucked into the plane thing 😪😂

  • Rook_Gacha *
    Rook_Gacha * 7 days ago

    What is a shade ball-

  • Ilias 12
    Ilias 12 7 days ago

    Is this plastic!!

  • Eddie_ swag
    Eddie_ swag 7 days ago +1


  • Daniel Chiasson
    Daniel Chiasson 7 days ago

    Bird going through the plane at 5:53

  • Chanderdat Laltoo
    Chanderdat Laltoo 7 days ago

    hi...im interested in knowing more about these balls. can you indicate me to the company that manusfactures it. Thank you.

  • Black Man
    Black Man 8 days ago

    Sellur raju ta pesureya ... manda bathram ....

  • Kamar Deen
    Kamar Deen 8 days ago +1

    Any sellur raju fans😜✌🏻

  • Karma Tv
    Karma Tv 9 days ago +1

    Yapacağınız alt yazıya sokam aq

  • Wesley Lecler
    Wesley Lecler 10 days ago

    Surely boats waste petrol oil which wouldn't be good for drinking water

  • Spider 2.0
    Spider 2.0 10 days ago

    Looks like those slime balls from the incredibles

  • Natu Davis
    Natu Davis 10 days ago

    They're black becasue if they were clear/white they wouldn't last in the sun...
    Hence the reason black people have high heat tolerances and we don't suffer from sunburn...
    BLACK is amazing✊🏾

  • yurik unt
    yurik unt 11 days ago

    Don't drink LA water!

  • Titanic
    Titanic 11 days ago

    So how well would the Titanic move through shade balls?

  • Princess Azarcon
    Princess Azarcon 11 days ago

    TVclip: ohhh great darling you're one of the 39M viewers of this video.
    me: dude did you see the bird? (._.")

  • Fais kareem
    Fais kareem 11 days ago


  • Luhong Zhang
    Luhong Zhang 11 days ago

    Hi Veritasium, thanks very much for providing excellent videos for us, I have subscribe your channel for years. I have learned a lot from watching your videos. Moreover I was inspired by this video at this time. Instead of reducing the evaporation of water or preventing the generation of bromate, I really intend to accelerate the evaperation of the water by improving the balls into solid ones with mesoporous characteristic. As you know, Australia is a country surrounded by sea, but you cannot image how could it be a droughty continent with surrounding water. Australia has a dry climate, and forest/bush fires are easily triggered, especially in winter. However, with the deterioration of the global environment, the fires are more frequent and out of control in AU right now. So may I have the official website for the producer of the shade ball? If feasible, I really want to discuss with them about some technical issues. And the purpose for the improved balls is supposed to be used into accellerating the evaporation of water and regulating the climate in Australia and finally reducing the bushfires.

  • Oh Ngonoo
    Oh Ngonoo 11 days ago

    What a genius Mr. Beast!

  • dustiest spade
    dustiest spade 11 days ago

    Bro I'm not like that bro.

  • jackie b
    jackie b 11 days ago

    WoW !!!!!!!!!!!!!

  • Jane Bravo
    Jane Bravo 11 days ago +1

    I don't know why, but this video make me nervous, I'm the only one?

  • 땡이
    땡이 12 days ago

    그래서 저걸 왜 부은거죠..? 뭔가 의미있는 일인거 같은데 뭔소리를 하는지 모르겠네

  • Gina Editz
    Gina Editz 12 days ago +1

    5: 52 who sat the bird fly into the jet?

  • Emir Aydoğmuş
    Emir Aydoğmuş 13 days ago

    vay amk

  • jrml7
    jrml7 13 days ago

    Every penalty failed by Ramos is there

  • Alp Eren Gül
    Alp Eren Gül 13 days ago +2

    No one cares about fishes?

  • Nick Scheidt
    Nick Scheidt 13 days ago +1

    Jesus loves you

  • Mark Russell
    Mark Russell 14 days ago

    How long do they last before you need to replace the balls?

  • c3t
    c3t 14 days ago

    if anyone was wondering they spent like 3.2 million dollars on all those balls