What stops rain from flooding your city?

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I’m a civil engineer specialized in water resources and you did a fantastic job making such critical (yet mundane) infrastructure very interesting. Also great to see the actual manning’s equation when discussing open channel flow. Great work! I will definitely be subscribing.

17:27 engineering an entire building to waterproof the first floor with watertight doors and reinforced windows Andrew Lam: "small details"

The production value on this is incredible. You strike a rare balance of both teaching me new things and also making a palatable video that I can watch while eating lunch. Keep it up bro

I really hope all of those "I would need a full video to explain" bits turn into their own videos! I'm definitely interested to learn more about these projects!!

Easily the best video on stormwater infrastructure I’ve ever seen. You really made a boring topic EXTREMELY interesting. Shoutout to all civil engineers that do amazing work that nobody takes the time to appreciate.

10:40 In the Early 1980's there was a huge flood in my home town. A few years later I became friends with another kid who had been crossing a flooded street. He turned his head for a second and when he looked back his friend was gone. The water was a bit less than knee deep but it was muddy so the road was not visible under the water. He thought his friend had just tripped and expected him to pop up in a second, when that didn't help he started to get worried and started walking around where his friend had been when he nearly fell into an open manhole. He called for help but this storm drain flowed directly into the bay and there was very little hope. They never did find a body. He said it was weird how you can be talking to someone one minute and the next they are just gone. There was no splash no cry of alarm, his friend was just gone. After this the city started welding the man hole covers on. Not so strongly they could not be opened, but enough that the water could not blow them open in a flood.

Oh boy I thought this channel was dead, glad to see you back!

Bro talked about water management without mentioning The Netherlands! Crazy!.

Underrated af. This video shows the shift in the philosophy of stormwater management, from making the problem go away as fast as possible (conveyance), to holding them in place for as long as possible and not let it be a bigger problem down the line (retention). Interesting thing about Tokyo and storm management is that it goes back to the Tokugawa Shogunate period. Edo is very flat and prone to flooding and as such the shoguns started flood mitigation efforts even during the Closed Doors period. They rerouted the most of the flow of the upstream rivers into Tone River, and in part making it the longest river in Japan. Then in the Imperial era giant bypass channels with giant floodplains were constructed, which uprooted quite a bit of homes. Not to mention dams.

I knew you were going to talk about Philadelphia at some point. The city and its largest neighboring county, Delco, are both BELOW sea level and adjacent to the Delaware River. We've had heavy flooding in the past but it has improved significantly over the years. During hurricane Sandy the only thing preventing my house from being swept away was the genius engineering of the river right behind my property. I remember right after the storm sitting at the edge watching the water speed past what must have been over 30 miles an hour. In Ridley Park there is a gigantic recreational field called the "Hollow" that sits in a massive valley, with a small river at its bottom. Back in the 90s, according to my parents, the entire park used to be a lake. Now it's part of the genius engineering that keeps the area dry.

Great video! It’s disappointing to see the video doing so poorly, YouTube needs more content creators like you! You’re one of only a handful of creators I have notifications on for.

Truly amazing the amount of time you dedicated to this is incredible. I also loved your detailed animations and even quick but still visible mathematical explanations. You also gave me some really cool japan visit ideas once I eventually can do that. I might suggest in the future though that maybe you try to collaborate with other creators to save you time on your hard work. I could see that you looked at practical engineering's video but maybe it might be a good idea for you to reach out for experts to explain topics to you instead of trying to understand it by reading (and losing those 8 hours for the math part/animation and everything). That hard work definitely paid off in the quality of this video just an idea to try to save you time but it's not necessary if you can't or prefer not to make your videos that way.

Shout out to the Manning Formula! As a young civil engineer 35 years ago, I was given a circular slide rule that was based on the Manning equation and it was so intuitive to properly size storm pipes — and is just as handy today even with the proliferation of computer software.

Tom Scott, but with more substantial information.

This video is extremely valuable for us here in Brazil 🇧🇷 . We faced the most devastating flood ever in the south of the country, and I believe events like these (heavy rains) are going to be more common. Thank you for your research and work!

I'm here from Tom Scott's newsletter, and I'm so so glad he linked this because this is the awesome content I'm always looking for :D It kinda reminds me of The B1M!

18:24 that mirrors edge nostalgia never hit so hard.

Superb video. Deserves way more views

I love the both of them. Everyone loves the added greenery, and it's inarguably needed in such barren wastelands that is of modern infrastructure. I would have liked to have seen the rivers get more beautification as well, that way they aren't just concrete. The massive feats of architecture and engineering are not also a method to secure reliable function during the most dangerous of storms, they are also incredibly impressive and undeniably cool.