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

  • Published on:  5/10/2019
  • 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 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.


  • Tiznado (May 10, 2019)

    Veritasium: It’s really rare to see 96 million of anythingSand grains: Am I joke to you?

  • Gas Menocide (5 hours ago)

    issaciams nah

  • RUHDD4HVN (4 days ago)

    Okay I'll say it....... "It took a lot of balls to make this video."

  • justblaze2323 (7 hours ago)

    Lolololololol lolol 👍👍👍👍👍👍👍👍

  • Mostknown Unknown (15 hours ago)

    fucktard....nice 1

  • "It’s really rare to see 96 million of anything"The 9 year old army: *_ARE WE A JOKE TO YOU?_*

  • Ashutosh Bhat (10 hours ago)

    +wtcamer can you see the 9 yr old army?Jesus you guys are just dumb

  • Joseph Kony (16 hours ago)


  • Let's drive a boat through the water we are drinking, boats have to release some oil and contaminants

  • Michael Wooda (26 minutes ago)

    Most rivers contribute to our drinking water.so the next bridge,jump over and get all the boats out.oh yea,clean everyone before they take a shower!!that water is also used to drink.

  • jeremy bourbeau (2 hours ago)

    Boats with outboard motors do not release any kind of contaminants into the water whatsoever.

  • Truck Taxi (3 days ago)

    $32M you know the manufacturer was extremely happy with that order

  • tagsdaddy (4 minutes ago)

    How else do you get BPH into the rest of the states population that refuse to buy water in plastic bottles.. Give it a generation and California will be ALL women... Good for them, but good luck reproducing...

  • Sam (3 hours ago)

    Or just drink carcinogenic drinking water and save money

  • polt (May 14, 2019)

    Jesus christ, I finally watched it youtube are you happy?!

  • Em Rah (3 hours ago)


  • Patricia Nastasi (3 hours ago)

    polt: Just curious.....why do ppl use Jesus’s name or God’s name in place of your own or something else?

  • Steve McGee (4 days ago)

    There are so many jokes to be made here that the only REAL option is just to make a joke about how many jokes can be made here.

  • Zodayn (2 days ago)

    If you ask a chemist if you're friends what does he say?You're my BrO⁻ ₃

  • RandomEmyr (11 hours ago)

    For those small souls who do not get this, BrO-3 ( I can’t do it with on my phone) is the formula for Bromate.

  • Samuel Pearlman (20 hours ago)

    +Opposite34 Yup, family can be toxic

  • Airlea Mystery (4 days ago)

    I love how excited and enthusiastic the guy in the grey suit is

  • Stoic (1 day ago)

    I just thought he was excited to talk about balls.

  • Arturas SA (2 days ago)

    Exactly my thoughts :D

  • GERMARDOU MEDIA GROUP (4 days ago)

    5:50 R.I.P speckled bird@ least yo u got 30M views (MAYBE)

  • wildflower (17 hours ago)

    Wow, he got turned into a bird spray