How Different Spillway Gates Work

How Different Spillway Gates Work

If you ask me, there’s almost nothing on this blue earth more fascinating than water infrastructure.
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Almost all dams need a way to release excess water when the reservoir is full. Although many dams use uncontrolled spillways, gated spillways provide more control over the flow, allowing us to build smaller, more cost-effective structures. There are countless arrangements of mechanical devices that have been used across the world and throughout history to manage the flow of water. But, modern engineering has coalesced to variations on only a few different kinds of gates.

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Practical Engineering is a YouTube channel about infrastructure and the human-made world around us. It is hosted, written, and produced by Grady Hillhouse. We have new videos posted regularly, so please subscribe for updates. If you enjoyed the video, hit that ‘like’ button, give us a comment, or watch another of our videos!


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27 Responses

  1. Practical Engineering says:

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    • Kingsblend420 says:

      So Dams are some of the most fascinating infrastructure out there IMO due to the hostile conditions, the immense amount of force, and weight they hold, the difficulties installing them, and the oddities that dealing with water brings. Great video learned a lot 😀

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  2. 5t4n5 says:

    There’s just something about the power and strength of water that just does it for me. Incredible.

    • bucky13 says:

      The fact that it’s the height of water that determines pressure, not the volume, still blows my mind some reason. I’ve yet to have that explained to me in a way that makes sense.

    • Edwin Salisbury says:

      @5t4n5 Richard Trevithick knew that when he started tinkering with high pressure steam and realized how engines could be made more compact if higher pressures were used. Most watt steam engines only ran on 5 psi of pressure, trevithick’s ran on 50+ psi.

    • 5t4n5 says:

      @Edwin Salisbury Totally agree. It’s incredible stuff when we stop to think about it.

    • Junior Junison says:

      @Edwin Salisbury yep, ice can move mountains

    • Edwin Salisbury says:

      Not just liquid water, steam is very powerful and strong too, oh and the thermal expansion of water freezing is powerful.

  3. Steve Strummer says:

    Hey Grady – after dropping a few hints, I received your new book as a Christmas present! I have to say it’s really well written (and illustrated) and I’m already looking at the constructed world with different eyes 👍 Good luck with sales for the book and a Happy New Year from The UK 😊😊

    • M. Gustafson says:

      Looking for the little Grady and the various situations in the illustrations is one of the best parts! 😎✌🏼

  4. Graham Rule says:

    It would be interesting to hear how the gates used at the Thames Barrier compare with the spillway gates you’ve described here.

  5. JuzzyBro says:

    4:09 I love the implication there’s one if not more interns with the physical strength to manually operate hydroelectric systems.

  6. TheMotlias says:

    Am I the only person who loves Dams, but is also similtaniously a little scared of them when I’m near them? like the amound of water and pressure there is a bit intimidating

    • Dane Randel says:

      Definitely not. In a class with standing on cliff edges or around spinning machinery. I was getting kind of queasy when he was talking about walling off gates in order to do maintenance, just imagining being the person tasked with working inside of a gate and being expected to trust everything around me to that degree.

    • Eily Bergin says:

      Same! I love to watch yt videos about dams, spillways, hydroelectricity, turbines, rotors, stators…but would not go near one of these structures in real life. 😄 You have probably already seen it but my yt tip to watch would be the video of the “Obere Wasserschlosskammer” and other videos of this “Edgar Müller” channel. The walkthrough of this chamber etc. Terryfiying, yet absolutely interesting.

    • SuGo says:

      I snuck into a small river dam used for power production, years ago.
      It was enormous inside, and climbing the metal hoops ladder and catwalks hanging inside a spillway really put things into scary perspective.
      I saw a couple dark tunnels towards the mountain into which water rumbled noisily, sucking air along with them; standing on the edge of that dark tunnel was by far the scariest part, beating even climbing up the concrete sidewall on small rusty hoops!

      And to think it was just a tiny valley stream…

    • P Ferris says:

      Yes! Me too! What really scares the wee out of me is a hydro electric dam, I’m fine watching them on screen, but no way do I want to get close to one. 😅

    • cory lytle says:

      Yes, and low head dams terrify me.

  7. Tom Kelly says:

    Wow, that was interesting, the systems seem so simple but the scale of dams is immense! Those are some serious hinge pins!

    I wonder if in the future you could do a similar video comparing fish spawning ladders and what kind of improvements are possible with our current dams?

  8. Paul Haynes says:

    Those stop log things are used on the canals over here in the UK. Except they are planks, not logs, as there’s very little flow, and therefore only low water pressure in our canals (which are also very shallow).

    They are used to isolate sections of the canal so that lock gates can be replaced, etc. And also, if there’s a breach on a section where the canal is high up – otherwise the entire contents of that section (which can be miles long) would drain away!

  9. Captain Patch says:

    Clearly what we need is to engineer stronger interns to do it at full scale.

  10. ToIsleOfView says:

    As always this is a superb explanation of a very complex and dangerous (if it fails) part of everyday modern living. I learned a lot and was entertained as well. Keep it up!

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