Roppongi residents pour water on the street to lower the temperature in the area. The custom is known as "uchi-mizu" in Japan.
© Japan Today
Roppongi
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Roppongi residents pour water on the street to lower the temperature in the area. The custom is known as "uchi-mizu" in Japan.
© Japan Today
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lipscombe
mayybe this is what the Prince is teaching them in Spain
imagawa
No, we have had a little help from the "gods".Yes, rain in July, very odd, but really quite nice too.
I'm told Sapporo isn't in need of any human watering either
hikikomori08
Yeah that's what happens when you pave over everything with concrete. Grass does wonders for lower temperatures and quality of life. But Japan doesn't like grass. It likes grey, and gravel playgrounds so kids end with up with pretty scars on their legs. Such a poor country.
Saw on tv some guy measured the temperature at one place. Volumes of water on the street and how far did the mercury drop? One degree. One.
Uchimizu is nothing more than a blatant disregard for water conservation.
some14some
Mizumizushii - the one at the left !
DeepAir65
I don't get this - isn't it called wasting water that thousands could survive from?
Near our house there is a big humidifier outside a shop pointing at the shop opposite - isn't it humid enough here already?
KissMint
Where's the "Mottai nai" campaign now??
electric2004
They are using pet-bottles. No need to use drinking quality water. Using collected rain-water - this would be actually environment friendly. But - zannen.
haytkayokomiya
And increasing the humidity.
PrinceskaNo1
it is so hot. Instead of sitting in front of computers, you should all go out and pour some water and reduce the temperature.
nisegaijin
I thought my neighbors were smarter than that.
stop wasting water!!!!!! it's not even that hot, just humid, and they ain't helping
kinniku
I am constantly reading this opinion. However, the picture is of a city, not the countryside. One can expect concrete and pavement in the city, any city. There are plenty of areas in Japan that are not paved over with concrete. Get out of the city if you want to stay cool.
PrinceskaNo1,
Although it is a great picture and a quaint custom, I am not sure it helps much in a giant city like Tokyo.
Alphaape
if they are using rain water, where did they get if from? It hasn't rainded in some time. How about planting a few more trees and green spaces. Maybe that would help the environment.
USNinJapan2
If any of you saw this story on TV yesterday or read the original article in its entirety you would know that the water used for this uchimizu campaign was collected rain water and the PET bottles were borrowed from the recycling center (and returned). Uchimizu is a practice that's been around for centuries, long before any part of Japan was ever paved with concrete. Uchimizu was traditionally done using already used water like bathwater, and that's what this campaign was urging people to do as well. The news show I saw measured the effects of uchimizu and showed the area 3.5 degrees C cooler after uchimizu. There's also a psycholigical cooling effect, same as with the fuurin bell. As long as fresh water isn't used I don't see any harm in this and certainly don't think your outrage is justified or proportionate.
USNinJapan2
Alphaape
The rainwater came from the vast collection reservoirs under the city, again according to the TV news.
Alphaape
I stand corrected.
nath
Zombies.
Sarge
As soon as that water evaporates, the effect is gone, no?
bamboohat
Come on people, it's more a tradition (at least in the city) if nothing else. Sure, in small towns when they water the street with a hose or something in front of shops you can actually feel the difference.
UnagiDon
USNINinJapan2;
Facts trumping hyperbole on JT?! You've got some nerve there, bub.
tkoind2
Agreed this makes me angry. There are a lot of people in the world who would nearly kill for that wasted water to stay alive. This doesn't help the temperature, wastes water and shows flagrant disregard for conservation.
Agreed, plant some trees, grass and brush to help things. Turn down the aircons and stop over hearting the city with their exhaust. And let people go home earlier in the day and chill out at home outside the city where most workers live anyway.
PrinceskaNo1
They shall water the trees, the flowers, the grass. Throwing water on the concrete is nonsense. On the photo, there are flowers behind the backs of the women pouring water. none of them waters the flowers, how cruel.
evil_robot
Too bad we can't broadcast this image to those thirsty African kids who can't get any water. Japan is just this wonderful country of waste and overuse, where you can leave the tap water running all day, pouring out into the streets. Where you can open all of your windows and doors and turn the AC to maximum blast in your shops. Just more waste...
Taka313
Seems like a waste of water to me, but, it also keeps the dust down, so I can't complain too much.
Altria, I like your thinking.
Taka
UnagiDon
Wasteful maybe, but before the casual condescension and self-righteous comments get too sickening, note that if you're from Australia, Canada, or the US you're probably using and wasting way more water than a Japanese person, so you might want to cut down on your own waste water and ship it off to those poor thirsty kids in Africa or wherever.
mindovermatter
Roppongi residents pour water on the street to lower the temperature in the area.
Now this is just flat out crazy....
Hughgarse
what a load of rubbish.. All it does is make it more humid..think about it.. pouring water on roasting concrete will just make it steam, not cooler! nutters....
Zen_Builder
Actually not all that wasteful. Those under-water reservoirs need to get emptied from time to time as the water gets old and stale.
Same with the water that Fire-engines carry, in many countries you can ask the fire-brigade to come and fill up your pool using that "old" water.
The water is collected in case of emergencies. Often large open areas like outside shinagawa station are collection points with the tank underneath the plaza, etc.
RepublicofTexas
It's just an old tradition, and it's not like they're opening the hydrants and wasting large amounts of water. The water's probably used bath water or laundry water or something. It's not meant to make a big difference, or waste a lot. Every country has it's quirky customs and traditions, live and let live.
Jandals
maybe they should stop wearing full body track suits in peak summer...just a thought
blvtzpk
UnagiDon:
How do you work that out? Talk to people in Australia who are going through level 3 water restrictions.
Moderator: Back on topic please. The subject is the custom of "uchi-mizu" in Japan. References to other countries are not relevant.
DeepAir65
I've never seen any rain water collecting here in Japan so I am sorry I don't buy that argument.
Zen_Builder
Wow, strong argument.
I haven't seen it so it don't happen.
Lots of reports on those systems on japanese telly. They also explain how a square like the one outside shinagawa stations drains the water faster and collects it.
Like all the small parks in the narrow back-streets of Ikebukuro are actually there for fire-fighting as the roads are too narrow for the fire-engines, each has a water reservoir underneath it.
Or the parks that double up as emergency evacuation areas, they also got them in addition to "hidden" toilets, etc. I know as we got a few of those in area and they are well-posted with what features, etc they offer.
Plenty of cases out there and the info is readily available.
USNinJapan2
DeepAir65
What do you mean you've never seen any rain water collecting here in Japan? Where do you think the water that falls on all that concrete in cities like Tokyo, Osaka, etc. goes? It goes down the drains into rain/flood water reservoirs and eventually into the ocean. Ever seen this Range Rover ad? It's only a commercial but it was actually filmed in the rain water reservoirs we're talking about here. Their existence is pretty common knowledge for Japanese people as it's been covered occasionally by the media. http://jp.youtube.com/watch? v=Skp81uz8ZL8&feature=PlayList&p=D0E6C5BE765B62EC&index=29
ellissan
Yes, by all means it's more a symbolic act that Japanese practice as a tradition. A Japan is rich in traditions. On the flip side, for those rushing to the conclusion that Japan wastes water without a care, consider that when families take a bath, they tend to soap and rinse thoroughly, but they share the water in the common tub. In other countries, gallons upon gallons are washed right down the drain per person in tubs and showers each day. I'm not criticizing how other countries do it, just calling out that there is a difference.
timorborder
Saw a couple of drunk guys down Roppongi a couple of weeks ago doing this same thing early in the morning.
Piglet
Well this should be seen as a cultural tradition that should be respected, but I don't think anybody considers it to be useful. Actually, pouring water on buildings during summer can be a good and economical way to fight against heat and decrease the use of AC. It can decrease the temperature of the walls and roofs up to 2 or 3 Celsius degrees. It is not uncommon for big companies to use this method during the hottest days (I've never seen it yet in Japan, where surprisingly people keep the doors and windows open in summer in my company, while switching on the AC).
Alphaape
Maybe I am missing the concept, but it rains in America, and I understand the water cycle (I took a class in civil engineering in college), but I always understood that when the rain fell, it is absorbed by the ground, and the runoff normally makes it way to the oceans or resivors via rivers and streams. So, you are telling me that in Japan, the rain water is collected under the city and just stays there? Doesn't this flow to resivors, lakes and eventually to the ocean. In most cities in the US, these rain water collecting systems are called sewers.
asdfghjkl
Its funny how when it is a non-western country doing these type of things are a custom or practice. However when its in a western country, its not described this way.
Pouring water does make it cooler though. And its OK if there is enough water around.
Ah_so
A "custom"? It is practical in hot countries. It is regularly done in Turkey in summer months (although not on pavements) and it hardly ever seems to rain there. If you have the water to spare, it is a practical thing to do, so hardly a quaint "custom".
This is not "wasteful" of water. Japan has lots of water - it is a very wet country and there is no shortage. The water is just going back into the rivers via the drainage system. There may be countries around the world with a shortage of water, but Japan is not one of them and we have not yet reached the stage of shipping water around the world to relieve relative water shortages (as opposed to drout emergencies).
Alphaape
The woman with the bottle in the foreground (in yukata) that is the clearest looking rain water that I have ever seen. Those rain collection systems must be kept pretty clean to get water like that.
But, since I am learning about the Japanese traditions, and from the posts here this seems to be an old one, then good on the participants. Keep up the work on preserving your cultural traditions.
Sarge
They need to use sprinklers, not pour the water from the bottles.
USNinJapan2
Alphaape
Have you ever been in any American coastal cities or towns that have two types of storm drains and sewers, those that aren't differentiated and those that are clearly marked as draining straight into the ocean? You can dump 'dirty' untreated water into the former but not the latter. You see this a lot in California. The drains that lead straight to the ocean are designed to keep large amounts of rainfall from overloading the sewage system. Rain water doesn't need to be treated so there's no need for it to enter the sewer system. Tokyo (and many other Japanese cities) have similar drainage systems. In a city like Tokyo where the majority of rainfall isn't absorbed directly into the ground because of the large amount of paved area, the rain water is directed into storm drains that collect and direct the water to large canals that eventually empty into one of the major rivers or directly into the ocean. Some of the water in these canals are redirected into huge underground reservoirs where the water is kept for emergency use, periodically being emptied and refilled by fresh water to keep it from going stale.
hikikomori08
As for those buying the rainwater claptrap, well that's a nice thing to say in front of the cameras isn't it? Fits in nicely with the whole eco thing. But what about the tens of thousands of shop owners splashing water on the dirty pavement and thus mud all over the place? Using rainwater? Nope. Water straight from the kitchen tap? Yep. Eco? It's just so hot today.
USNinJapan2
hikikomori08
That's why they ask citizens to use bathwater instead of fresh water just like they recommend filling your washing machine with the same. But I guess if you choose not to listen...
hikikomori08
Hands up number of citizens, Japanese or otherwise, who waited for their used bathwater to cool down and then cooled it in the fridge so that it may have any cooling effect outside on the dirty pavement? And hands up the number of citizens that brought their dirty used bathwater to work and splashed their germs all over the pavement on the street? What a quaint but dirty custom.
borscht
I think if they hosed the concrete down the temperature would also go down, but dribbling the little bit of water they seem to be doing in the picture won't affect the temperature much nor the humidity. It's symbolic, if nothing else. And a good excuse for a Party! Bring on the cold beer! By the way, a recent Japanese TV show showed that the average US citizen uses less water than the average Japanese citizen. (Despite the bathing habits in both areas of the world.)
UnagiDon
USNnJapan2;
Well said.
Alphaape
USN, I have lived in San Diego and Honolulu as well as on the banks of big rivers in America as well as here in Nippon, and I am familiar with the difference between storm drains and sewers. When was the last time it has rained measurably this July? The drain outside of my home in Yokosuka still has a little water in it, but not much. My only comments were that it looks like the water seems pretty clear to me than to be run off. Not knocking the customs and traditions of Japan at all.
nath
At least it is doing something, realistically cars have got to go, the sooner the better, eliminate concrete and blacktop, plant trees. That is culture I could live with, anywhere.
USNinJapan2
Alphaape
My previous comments about foreigners blindly ridiculing local customs and traditions weren't aimed at you.
I don't know how much rain we've had this July but I don't think it's relevent because having these vast underground reservoirs means you can collect the rain when it falls in abundance and save it for when you run short on water supply. I don't know if the water is purified in any way but I imagine that considerable settling occurs while the water sits in the reservoirs. Did you check out the link I posted earlier? It will give an idea of just how enormous these underground reservoirs are. Here it is again: http://jp.youtube.com/watch?v=Skp81uz8ZL8&feature=PlayList&p=D0E6C5BE765B62EC&index=29
PrinceskaNo1
In Japan the whole family bathes in the same water, then they use the dirty water to wash their clothes in the laundry and then they use this water to cool the cement. Great cycle!
Wottock_Hunt
USN: I just checked your link out, and, impressive as the architecture is, I did not see any water about. What I saw (working on the assumption that it wasn't just a bunch of CG) was a huge storm drain, designed to deliver water out of the location where it landed and towards the sea. Not a reservoir by any stretch of the imagination.
And, when you think about it, that is probably for the better. Can you imagine the disease potential of lakes of stagnant water beneath a city this size?
I suspect. like many things old ladies like to do, this is an empty ritual into which the minimum of effort but the maximum of pointless fussing was put. In short, they're pouring tap water on hot concrete.
Just what we need - more moisture in the air.
Couple of trees? No. What we really need is a bunch of old women who think they know everything.
KitsuneYoukai
I'm sorry you guys but unless you are pouring out the water for long periods of time, pouring water from bottles onto hot pavement will not make it cooler. Does anyone know their chemistry!!!! That water is going to evaporate so quickly if it is as hot as they say and that steam rising is not going to be cool.
USNinJapan2
Wottock Hunt
If you search Google Image for 'underground reservoir Tokyo' you should see a few photos listed from flickr. Sorry the link for the photos are just too long to post. You'll see that they're not drains that transport but reservoirs that hold rain water.
Wottock_Hunt
USN - did that, still found nothing to convince me, but assuming you're right I think it's a pretty safe bet the water in these bottles did not come from a trip down the underground reservoirs. They turned on the taps and threw good water away because an old crone told them to. This is Japanese culture - ahhhh so, desu ne.
USNinJapan2
Wottock Hunt
I don't want to drag this out unnecessarily but here's the original story in Japanese. Don't know if you can read it but the last line clearly states that the 200 liters of water that was used came from the emergency reservoir located under midtown Tokyo. Whether or not you believe this reporting is up to you.
http://www.asahi.com/national/update/0722/TKY200807220306.html
WilliB
Funny thing, in a sauna people pour water on the hot stones to make it hotter. Here they think the extra humidity will make it cooler. Come again?
NagoyaGaijin
WilliB--in saunas, they dont pour water on the stones to make it hotter. They pour water on the stones to get steam.
As far as the sniping regarding this idea of pouring water on the street to cool it off. . . I dont know JUST how effective it is. I am willing to bet that the people who really believe it works will FEEL a bit cooler...and those who believe that it will only make things worse will FEEL a bit hotter...the mind is a powerful thing.