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

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  • ℹ️ Description
Why Are 96,000,000 Black Balls on This Reservoir? 5
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

And from Kevin MacLeod "Marty Gots a Plan"

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

💬 Comments on the video

"Are they safe for drinking water?"
***Drives through lake with a gasoline-powered motor***

Author — Beau Bernier


“Did you think it was nuts?”

Nah they thought it was balls.

Author — Conor Malone


"It's very rare to see 96 million of anything"
PewDiePie: "hold my trebuchet"

Author — raveen mallawa


Do U know the movie "Inside Out"?

Is THAT the pit where all the deleted memories are dumped?

Author — desinfector


We all know their real purpose... to stop Mr. Incredible.

Author — LukeFili


It is so satisfying to see this. Looks like atoms on a large scale.

Author — Prakash Malathkar


5:52 the bird got smoked by that jet engine

Author — Hunter Pickering


The look on that professor's face is priceless as he's explaining things; he's so happy when he's talking about such a niche thing that's awesome

Author — Sunny Gandhi


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

Author — polt


Him: Rarely do you see 96million of anything

Me: Sand

Author — Ejay Harding


“It’s very hard to see anything 96 million things”

Grass: am I a joke to you?

Author — alexander movsesyan


me: i wan-
brain: don't
me: i want to-
brain: *don't*
me: i want to drown in this

Author — Kianush


"Is it hard to drive in shade balls?"
"It is hard"
"Why is that?"

Dude... Really? =_=

Author — Qayyum Chariff


Veritasium: It’s really rare to see 96 million of anything

Sand grains: Am I joke to you?

Author — Tiznado


"It's rare to see 96 million of anything"

jeff bezos: hold my cash

Author — Sticky Note


"Why are they black?"

Me: "oh my god you can't just ask balls why they're black!"

Author — Sock Gremlin


“Why are they black?” SHOULD THEY BE WHITE THEN?

Author — Jumpouttawindow Beech


“It’s very rare to see 96 million of anything”
YouTube comments:

Author — Truffalachubbles


That bald guy is super excited about his job and I love it.

Author — Noerdy


“It’s very rare to see 96 million of anything”
Pewdiepie: *laughs in Swedish meatball*

Author — Reoz