Tokyo's Underground Discharge Channel(en.wikipedia.org) |
Tokyo's Underground Discharge Channel(en.wikipedia.org) |
I've been following the Chicago Deep Tunnel project, which is nearing completion after half a century of work.[1] Because Chicago was built on swampland and next to the lake, rainwater used to be a huge problem because it didn't have anywhere to go when it rains, except into sewers - which used to be well under capacity for burst rainfall, which led to basement flooding etc.
So the city is building (and almost finished with) a set of huge tunnels across the entire city that regular sewers will drain into during flash floods, and then pump the water out to reservoirs repurposed from abandoned quarries on the edge of town. The target capacity is 17 billion gallons, which is apparently the volume of twelve football stadiums stacked together? [2]
I'd love to tour that construction. Not sure they offer public tours though. :)
[1] https://interestingengineering.com/chicagos-deep-tunnel-proj... [2] https://www.mwrd.org/irj/portal/anonymous?NavigationTarget=n...
I understand that football stadium play area is standard, but how do you measure height? Is it a foul to kick the ball too high in the air? The play area, I assume isn't limited vertically.
1. https://wgntv.com/2019/05/01/video-captures-street-buckle-in...
A couple years ago we stopped by the Lincoln Oasis (rest stop consisting of a bridge over the interstate that carried restaurants and similar instead of traffic.) As I was heading back to my car, I heard a loud whooshing noise and saw what looked like a geyser next to the ramp to get back on to the highway. I walked over to inspect and found a large grate fenced off and signed Chicago Water Reclamation (or something similar.) We had had a lot of rain the night before and apparently this was a vent to release air as the tunnel filled. The location is very near one of the quarries that is used to hold excess runoff.
BTW they do offer tours of the pumping stations, but not the tunnels [2]
[1] https://chicago.cbslocal.com/2019/05/01/heavy-rain-flooding-... [2] https://www.mwrd.org/irj/portal/anonymous/tourinf
https://www.mmsd.com/what-we-do/wastewater-treatment/deep-tu...
https://www.scientificamerican.com/article/sewer-diving-milw...
There is a software for modelling drainage systems called SWMM (Stormwater Management Model) that has been around since 1970s (!) and is programmed in C and released as free software. Still most modern drainage and sewer research is modelled via this software and there are several companies that built a GUI for simpler usage. However the core is often still based on this nearly 50 year old software which I find amazing [edit: it has been updated since then and originally it was written in Fortran].
The model has hydraulics and hydrology capabilities [0], i.e. it can model stuff like pipe pressure but also takes infiltration of stormwater (aka "rain") into the surface into account. When using it you have to define your sewer (which is mostly a directed graph) and so called catchments where you define which areas drain into which nodes (inlets) by defining parameters like impervious area, slope, etc. You can then let it rain on your area of interest (e.g. a city) and find out which nodes get flooded at specific points in time (or hopefully not).
[0] https://en.wikipedia.org/wiki/Storm_Water_Management_Model#H...
Note: it's about 1.5 hrs (each way) from Tokyo, and you need someone in your group who can speak Japanese.
Reservations here: https://reserva.be/guidetour
http://www.bbc.com/future/story/20181129-the-underground-cat...
Wow, I hope the grid can handle the relatively sudden appearance of 780 MW of load. I assume they have some protocol in which why turn on one pump at a time and coordinate with the grid operators.
Flash flooding is a thing. In Hong Kong, the Drainage Services Department puts up warnings and runs TV ads to tell people to stay clear of discharge channels, lest they get swept away by flash flooding during heavy rains.
So if intake into the discharge channel is not controlled, isn't it kinda dangerous to film there?
Tokyo was built on an estuary so the canals came from the management of the water that was already there. The final evolution being the water being pushed completely underground is pretty predictable. Other cities have dealt a similar fate to their rivers, London being a prime example where only the Thames is really 'welcomed' as a river, everything else is kind of banished underground.
https://en.wikipedia.org/wiki/Bombing_of_Dresden_in_World_Wa...
“Large variations in the claimed death toll have fuelled the controversy. In March 1945, the German government ordered its press to publish a falsified casualty figure of 200,000 for the Dresden raids, and death toll estimates as high as 500,000 have been given.[15][16][17] The city authorities at the time estimated up to 25,000 victims, a figure that subsequent investigations supported, including a 2010 study commissioned by the city council.[18]”
It’s a tragedy none the less but that figure doesn’t seem actuate ?
You mean 39600 acre-feet? :)
You want a different source? https://www.britannica.com/event/bombing-of-Dresden
> The U.S. Eighth Air Force followed the next day with another 400 tons of bombs and carried out yet another raid by 210 bombers on February 15. It is thought that some 25,000–35,000 civilians died in Dresden in the air attacks, though some estimates are as high as 250,000, given the influx of undocumented refugees that had fled to Dresden from the Eastern Front. Most of the victims were women, children, and the elderly.
Regardless of the deaths, I understand the cultural tragedy of the destruction of Dresden is significant as it was an important intellectual center.
I had a friend who passed away recently who was a boy in the bombings and recounted with tears on multiple occasions, as a lifelong opiate addict, how he felt he had personally died at that time. I visited the city a few years ago and found the largely depressing husk of a city still under wishful reconstruction. The nominal activity of its touristic center was at direct odds to the clearly economically depressed suburbs mere moments away.
Just to be clear and provide context, the numbers the original poster linked were overbloated and inaccurate because it's a fictionalized neonazi talking point, like holocaust denial and white genocide in south africa. Some people get drawn into the, uh, wrong sources and start parroting the talking points without really knowing what they are helping to propagate, so the poster here might not be a racial supremacist or whatever, but it's something to keep an eye out for.