The Simple Genius of NYC’s Water Supply System

The Simple Genius of NYC’s Water Supply System

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Writing by Sam Denby and Tristan Purdy
Editing by Alexander Williard
Animation led by Josh Sherrington
Sound by Graham Haerther
Thumbnail by Simon Buckmaster

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46 Responses

  1. Greasaholic says:

    these videos never cease to interest me, as someone who isn’t really that much of a nerd. Sam never fails to make me interested in whatever topic. Thank you Sam!

  2. Ryan Lunde says:

    I’m a pilot and last week I flew into White Plains, right over the Kensico Reservoir for Runway 16. It was a gorgeous summer evening and all I could imagine was paddle boarding on the beautiful lake I was flying over. I noticed that there was no traffic on the water and no houses on the shore which seemed strange given the lake’s proximity to a huge population center. Later I figured it had to be part of the city’s water supply to enjoy such a lack of disturbance and I got to thinking about what goes into keeping NYC hydrated. This video had perfect timing to my logistical ponderings. Thanks for some more outstanding material.

  3. Matt_Kiefer97 says:

    Back when I did an architectural thesis focusing on the pollution in the hudson river, you touched on basically everything for the the NYC water supply, but a topic idea for the future could be looking at combined sewer systems and seperate sewer systems. The hudson river still has raw sewage dumped into it during heavy rainstorms due to the existing combined sewer systems in the towns and villages along the hudson river. Potential future video idea for ya

    • roberto xs says:

      Dude that’s what I was gonna say! Combined Sewers are wack and while they may have worked in the past, they’re really dangerous to continue operating today.

    • Space Elf Downlink says:

      @Requiem for a Meme ive always wondered why the city does not just pull off the bandaid and fill the canal in, I mean is it actually used for anything other than throw away jokes about pollution and three eyed Simpsons fish? that is does anything along it still depend on it for moving stuff on barges.

    • Requiem for a Meme says:

      It’s still weird to me that Gowanus (our very own Super Fun site) is labeled basically as “South South Slope” now-a-days, and is full of strollers competing with bicycles for parking space.

    • Liam Hodgson says:

      That would be a great vid. I’m in Pittsburgh and we are in the same boat, probably about 4 billion to fix. I wonder what the nyc cso fix would cost.

  4. Clara -My New Private vidoe says:

    its interesting that the next longest tunnel is for the Helsinki water supply which is a substantially smaller city and the tunnel is only about 10% shorter 😀 though the bedrock there is very stable so probably more afordable

  5. Flavor Lab says:

    When he said the physics of siphons was not fully understood, I had to remind myself that this was not Half as Interesting

    • Space Elf Downlink says:

      @bungalow bill I have honestly always thought it was once the fluid got moving it was pulling a vacuum in the line, And since a tube is sealed the only source for filling the void is more water. I make this opinion and support it by the fact that pipes for which the faucet can potentially cause backflow to the water lines of the building you have these little caps called a vacuum breaker, if water tries to flow backwards like it would with a siphon the little valve opens breaking the siphon.

    • stevenette says:

      I mean, they are pretty well understood. It’s like my old roommate saying “We don’t know how bicycles work!?” Like, yes we do, but there are just some minor physics contributing to the problem that are affecting it in a way not fully anticipated.

    • Kishanth Jeyamoorthy says:

      Jeez I thought that statement was just a joke but apparently not. The physics of siphons is not fully understood, how does interesting.

    • Flavor Lab says:

      @bungalow bill no I definitely don’t think he is wrong, but for some reason it felt like something that that wacky guy at HAI would say before cracking a joke about Applebee’s

    • bungalow bill says:

      Is he really wrong, though? The following is an excerpt from the 2015 paper ‘The height limit of a siphon’, published in Nature Scientific Reports:
      “Although the siphon has been used since ancient times, the means of operation has been a matter of controversy [CITATIONS]. Two competing models have been put forward, one in which siphons are considered to operate through gravity and atmospheric pressure and another in which gravity and liquid cohesion are invoked.”

      So while I don’t think it was really necessary to discuss the why at all in the context of this video, and enough to just mention how it works, I think the phrasing used in the video seems fine since it would be unreasonable to go into more detail.

  6. Jakub Hajtałowicz says:

    Man i wish this Half as Interesting guy made videos of this quality. You have no competition from him!

  7. Runescape Stats says:

    As a water utility worker I find this fascinating. The idea of not needing to filter surface water is truly unique. We actually filter ours twice. The first stage is mechanical particle removal and the second is adsorption of organic material

    • hydrolife tech says:

      @Mari Onette are you serious? NYC actually has a reliable water supply that is tasty, of such a good quality it doesn’t need filtration. If you watched the video and actually paid attention, you’ll find the lengths they went to to make sure the water is safe. Maybe you just want to whine because it is NYC

    • Mari Onette says:

      When you set your standards low enough, anything is possible.

    • ben knol says:

      @Adrian Lilholm from my understanding it also depends on how clean the pipes are. and unchlorinated tap water does definitely exist (such as in the netherlands)

    • Adrian Lilholm says:

      Does the filtering eliminate the need for chlorine, Or do you also add chlorine to the water?

    • Chaplain Bob Walker B. Th. says:

      another water worker here also and agreed

  8. Sumit Shrestha says:

    Its really a modern engineering marvel to see such a mega design that serves millions even now. Wish we had similar level of foresight now for our modern problems that could serve future generations.

    • James Bond says:

      @Gills1776 people literally can’t think more than 2 years ahead now… And that’s actually being generous. People used to think DECADES ahead.

    • Jonathan Odude says:

      We are trying but there’s a lot more pushback now after acknowledging our impact on native ecosystems and how that can affect farming fishing scenery and wildlife.

    • Kingsley Green says:

      Thinking about New York going green that would be some SCALE

    • Gills1776 says:

      It does seem that quite tragically, most modern people have lost the perspective of history for their actions.

  9. RTDragonCommando says:

    I’m actually hoping when they finally bring tunnel 1 offline we get some photos of what it looks like on the inside. No one’s been in there for over 100 years, they found out in the 50’s the sectioning valves were inoperable, so they couldn’t even shut sections off for maintenance. As it is right now, if a major failure happened in tunnel 1 or 2 it would be a huge disaster for the city, the capacity just isn’t there until tunnel 3 is fully operational.

    • Googie Gress says:

      Probably find a river of pink slime that reacts to emotions.

    • Saosaq Ii says:

      I remember seeing somewhere that professionals do scuba dive in the tunnels for inspection or something.

    • Nen Master5 says:

      More Water-Shortage-Coverage:
      -Some More News
      -Second Thought

      Were running out of Water and The Water Wars are Coming are Videotitles that
      maybe should make us all watch the videos.

  10. elijah31 says:

    Currently reading Empire of Water by David Soll which focuses on the history of NYC’s water supply. This presentation is just as informative and the images are something that books just can’t replicate. Great work!

    • Vigilant Cosmic Penguin says:

      I never would have thought “the history of NYC’s water supply” is a topic I’d be interested in reading about, but after watching this video I’m inclined to check out that book

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