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

  • Published: 10 May 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 • 61 614

  • amber gentry
    amber gentry  10 hours back

    Sounds like a good time to me

    • Himaja Challa
      Himaja Challa  12 hours back

      Did they remove them?

      • David Beruashvili
        David Beruashvili  21 hours back

        someone made a lot of money with his balls :D

        • KingCarrot Cake
          KingCarrot Cake  1 days back

          Veritasium:Why are they black???

          • Yveltr
            Yveltr  1 days back

            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  1 days back

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

                • Patrik VV.
                  Patrik VV.  2 days back

                  What happens after 10 years?

                  • Fredrickson the 96th
                    Fredrickson the 96th  2 days back

                    Jesus Christ... that poor bird!

                    • EXILE MEDIA
                      EXILE MEDIA  2 days back

                      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  2 days back

                        23k dislikes

                        • Hot Cheetos
                          Hot Cheetos  2 days back

                          The Reservoir: "You can eat shadeballs"

                          Eating Challenge Youtubers: Are you challenging me?

                          • D4RK-Th3 B0T B0t
                            D4RK-Th3 B0T B0t  3 days back

                            I read this in a magazine after a class test

                            • Keneth García
                              Keneth García  3 days back


                              • Tahir Khan
                                Tahir Khan  3 days back

                                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  3 days back

                                    5:52 poor bird

                                    • Ms. Lazy
                                      Ms. Lazy  3 days back

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

                                      • Rook_Gacha *
                                        Rook_Gacha *  4 days back

                                        What is a shade ball-

                                        • Ilias 12
                                          Ilias 12  4 days back

                                          Is this plastic!!

                                          • Eddie_ swag
                                            Eddie_ swag  4 days back


                                            • Daniel Chiasson
                                              Daniel Chiasson  4 days back

                                              Bird going through the plane at 5:53

                                              • Chanderdat Laltoo
                                                Chanderdat Laltoo  5 days back

                                                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  5 days back

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

                                                  • Kamar Deen
                                                    Kamar Deen  5 days back

                                                    Any sellur raju fans😜✌🏻

                                                    • Karma Tv
                                                      Karma Tv  6 days back

                                                      Yapacağınız alt yazıya sokam aq

                                                      • Wesley Lecler
                                                        Wesley Lecler  7 days back

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

                                                        • Spider 2.0
                                                          Spider 2.0  7 days back

                                                          Looks like those slime balls from the incredibles

                                                          • Natu Davis
                                                            Natu Davis  1 weeks back

                                                            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  1 weeks back

                                                              Don't drink LA water!

                                                              • Titanic
                                                                Titanic  1 weeks back

                                                                So how well would the Titanic move through shade balls?

                                                                • Princess Azarcon
                                                                  Princess Azarcon  1 weeks back

                                                                  Youtube: ohhh great darling you're one of the 39M viewers of this video.

                                                                  me: dude did you see the bird? (._.")

                                                                  • Fais kareem
                                                                    Fais kareem  1 weeks back


                                                                    • Luhong Zhang
                                                                      Luhong Zhang  1 weeks back

                                                                      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  1 weeks back

                                                                        What a genius Mr. Beast!

                                                                        • dustiest spade
                                                                          dustiest spade  1 weeks back

                                                                          Bro I'm not like that bro.

                                                                          • jackie b
                                                                            jackie b  1 weeks back

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

                                                                            • Jane Bravo
                                                                              Jane Bravo  1 weeks back

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

                                                                              • 땡이
                                                                                땡이  1 weeks back

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

                                                                                • Gina Editz
                                                                                  Gina Editz  1 weeks back

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

                                                                                  • Emir Aydoğmuş
                                                                                    Emir Aydoğmuş  1 weeks back

                                                                                    vay amk

                                                                                    • jrml7
                                                                                      jrml7  1 weeks back

                                                                                      Every penalty failed by Ramos is there

                                                                                      • Alp Eren Gül
                                                                                        Alp Eren Gül  1 weeks back

                                                                                        No one cares about fishes?

                                                                                        • Nick Scheidt
                                                                                          Nick Scheidt  1 weeks back

                                                                                          Jesus loves you

                                                                                          • Mark Russell
                                                                                            Mark Russell  2 weeks back

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

                                                                                            • c3t
                                                                                              c3t  2 weeks back

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

                                                                                              • Ian Mar
                                                                                                Ian Mar  2 weeks back

                                                                                                Just passed by this 😂

                                                                                                • Mi MIC Tv 76
                                                                                                  Mi MIC Tv 76  2 weeks back