Underground Tunnel Suggested As Solution To Bangkok's Flood Problems

[ratcatcher]

60 Posts later.

Fact: It will never get off "under" the ground. Never happen.

There will be people vacationing on the moon before this ever gets the go-ahead.. T.I.T.

"All sales talk, but nothing in the warehouse". or perhaps better still, " All fart and no shit"

[connda]

Uh-huh.

[chiangmaicharlies]

Put some boats in it and link it up to the MRT. Loadsa money saved!

[samjaidee]

That's more than three times the diameter of the Channel Tunnel.

The Chunnel is 50km long. This one's going to be 100km long.

The Chunnel's deepest point is 75m. This one is going to be deeper than Everest is high.

The Chunnel took six years to build this one is going to be done in two.

The longest road tunnel in the World is 24.5km.

Good luck!

Edited December 2, 2011 by samjaidee

[KeyserSoze01]

Once again Thai officials have made themselves appear like buffoons (or is that baboons) by making ludicrous statements to the media, without any sort of fact check on the accuracy of their statements. Reminds of the cowboys that couldn't shoot straight, the keystone cops and the 3 stooges all rolled into one.

[TheWalkingMan]

Stupidity abounds in certain areas.

[surangw]

Off course yes it's possible for water to flow uphill! don't you not know that?

It's really basic 3rd grade Physics! Even Romans 2000 years ago new about it.

To put it in layman's terms and compare you can use the same theory to syphon Petrol from one car to another with a long tube.

Look up Syphon in wikipedia to understand how it works.

Well here I found a basic explanation to help you understand.

http://en.wikipedia.org/wiki/Syphon

Beg to differ. A syphon will definitely lift the water up over a hill, or up the filler tube of a petrol tank, but it won't work unless the discharge end of the syphon is lower than the intake.

Specifically, quoted from the wiki link you posted, "discharged at a level lower than the surface of the reservoir". As such, a syphon won't lift the water from a ten KM deep source up to the surface. It would lift the water 10 km, but would need to discharge it at a level greater than 10 km.

dosen't the "tube" have to be full of the liquid for this to work? ( cars in water?)

[bino]

dosen't the "tube" have to be full of the liquid for this to work? ( cars in water?)

Yup. Would still end up needing the biggest baddest mother of all pumps to get the syphon primed and running after the highway tunnel became flooded for drainage.

[sparebox2]

Tunnel is OK. Just be careful of fire. What if a LPG SUV collide with a CNG taxi inside.

Edited December 2, 2011 by sparebox2

[saintofsilence]

Put some boats in it and link it up to the MRT. Loadsa money saved!

Now I know why they want them submarines.

[ResX]

Off course yes it's possible for water to flow uphill! don't you not know that?

It's really basic 3rd grade Physics! Even Romans 2000 years ago new about it.

To put it in layman's terms and compare you can use the same theory to syphon Petrol from one car to another with a long tube.

Look up Syphon in wikipedia to understand how it works.

Well here I found a basic explanation to help you understand.

http://en.wikipedia.org/wiki/Syphon

Beg to differ. A syphon will definitely lift the water up over a hill, or up the filler tube of a petrol tank, but it won't work unless the discharge end of the syphon is lower than the intake.

Specifically, quoted from the wiki link you posted, "discharged at a level lower than the surface of the reservoir". As such, a syphon won't lift the water from a ten KM deep source up to the surface. It would lift the water 10 km, but would need to discharge it at a level greater than 10 km.

dosen't the "tube" have to be full of the liquid for this to work? ( cars in water?)

Yes. But it is still possible to have pressurized compartment for water and ambient condition. There are issues regarding to this but it straightly speaking, it is going to work.

[moonbarman]

Off course yes it's possible for water to flow uphill! don't you not know that?

It's really basic 3rd grade Physics! Even Romans 2000 years ago new about it.

To put it in layman's terms and compare you can use the same theory to syphon Petrol from one car to another with a long tube.

Look up Syphon in wikipedia to understand how it works.

Well here I found a basic explanation to help you understand.

http://en.wikipedia.org/wiki/Syphon

Beg to differ. A syphon will definitely lift the water up over a hill, or up the filler tube of a petrol tank, but it won't work unless the discharge end of the syphon is lower than the intake.

Specifically, quoted from the wiki link you posted, "discharged at a level lower than the surface of the reservoir". As such, a syphon won't lift the water from a ten KM deep source up to the surface. It would lift the water 10 km, but would need to discharge it at a level greater than 10 km.

Well all is good until the last sentence.

Starting point just has to be higher than the ending point end of story that's all!

If water goes 1000km below ground its the same! as long as the starting point is higher.

Also just because the water goes down 10km below Sea level doesn't mean it has to be released 10Km above sea level!! It can be released at any height as long as it's below starting level.

I'm not here to teach Physics but it seams a lot of members really aren't that well educated! So probably better they let there opinion be on what is possible and is not possible. Otherwise they is just going to maker themselves look a bit uneducated.

Also I can't find where in the article where it states the the tunnel will be 10km deep where does that come from??

P.s. does anyone have a link to the original tunnel story? I was away and didn't haver time to read it.

Can't seem to find it any more.

Archimedes screw, talking about uneducated people, please check the spelling and grammar of your post, thanks!

[animatic]

How can this not be satire from 'Not the Nation'? Even by Thai standards it's just too comical; 'Hey let's build the worlds' third longest tunnel in two years!'

It took them 6 years and 11 billion baht to build the 10.5km drainage canal from Svarnabhumi.

Not to mention this is bigger than The Chunnel under English Channel.

Not to mention this is for water that is within 2 meters up or down of most existing high tides

The only solution is to make 2 major water ways through Bangkok east and west

about 20 above and below feet below the Chaopraya mean high flood level.

from the large swamp north of Bkk, and funnel most water to it in high wet season,

and trafic over it all year round, through them when possible.

Essentially split the load fo the Chaoipraya 3 ways in high flood.

And make the space practically useful the rest of the year.

Otherwise you are Barking at the Boondogle Moon.

[animatic]

The power needed to make a suitable number of massive Archimedes screws keep up with this level of water would be FAR beyond reach.

[Estrada]

"and a depth of ten kilometers"

Is that a misprint or is it actually realistic?

Misprint or not, why stop there? Tunnel through the crust and beyond. Seriously though, the tunnel that would lie below sea level at both ends have any kind of chance?

My thoughts also.

It would become a stationary collection pond only. it takes gravity to move the water to the sea from rivers etc. One only needs see what happens to sewerage outlets etc....they flow backwards when overflowed at the outlet.

As was so often spoken about, during the high tides, the water could not flow into the sea, it backed up, in fact the reverse happens, the sea raises the level of the river and floods the land.

100km in 2 years.....1 km per week??? 200 billion..... yeah right!! TiT......land of miracles. 1 meter per week and 2000 billion. would be closer to reality!! a fleet of longtail propellors type idea!!! 100% useless.

Someone has not done the sums here, just a mis-informed pie in the sky idea to substantiate someone's job. They need some "real" experienced engineers to draw up a national flood relief plan, and i strongly suspect it wouldnt be Thai engineers. They need an international consortium, Japanese and Dutch maybe? to sort it out, for the future of the country.

If you read the newpapers you will realise that the tunnel is directed to Khlong Dan where pumps will lift the water into the sea. Khlong Dan is where the Airport drainage water pump station is located and also the Industrial Waste Water Treatment Plant for Samut Prakarn.

Having said that, this scheme at B200 Billion, is a waste of money (except to the recipients of the brown envelopes). The floods are caused mainly by excessive monsoon rains falling south of the main reservoirs in the North of Thailand, particularly the Yom River basin. The resulting flow was 5,500cu.m/sec and the Chao Phraya River can only handel 3,000 to 3,500cu.m/sec without flooding occuring. What has always been required is a large bypass waterway from Nakhon Sawan north of the Chao Phraya regulating barrage, to Khlong Dan, in order to handle the excess 2-2,500cu.m/sec, as well as uprating the capacity of the Thai Chin River. This has been proposed for the last 30 years since the first JICA flood Mitigation Study in 1983 approved by the King. Problem is that they only built the Kings Dyke to keep the rich people in the centre dry whilst exacerbating the flooding in the areas North of the King's Dyke which for all intents and purposes is a dam holding back the flood waters. The people in the Water World have been deliberately chosen to be sacrificed for the sake of the Island of inner Bangkok. This current proposal has been reported incorrectly as the depth of cover would be 10metres (not 10kms)due to the road being constructed on top of it. This tunnel is required only for the immediate areas north of Bangkok which were designed as flood plains for growing rice only which would flood during monsoon rains to a depth of up to 2metres deep. Anyone like myself will remember back in 1982 flying into Bangkok's tiny airport over miles of rice paddys with no houses in sight. There should have been no houses or buildings built on the flood plain until the Chao Phraya river bypass had been been built.

[Estrada]

How can this not be satire from 'Not the Nation'? Even by Thai standards it's just too comical; 'Hey let's build the worlds' third longest tunnel in two years!'

It took them 6 years and 11 billion baht to build the 10.5km drainage canal from Svarnabhumi.

Not to mention this is bigger than The Chunnel under English Channel.

Not to mention this is for water that is within 2 meters up or down of most existing high tides

The only solution is to make 2 major water ways through Bangkok east and west

about 20 above and below feet below the Chaopraya mean high flood level.

from the large swamp north of Bkk, and funnel most water to it in high wet season,

and trafic over it all year round, through them when possible.

Essentially split the load fo the Chaoipraya 3 ways in high flood.

And make the space practically useful the rest of the year.

Otherwise you are Barking at the Boondogle Moon.

Exactly what I have been telling the politicians and the irrigation department since 1983. They must bypass Bangkok with a new Chao Phraya Water Way from Nakhon Sawan.

[anterian]

Why all the sarcasm, surely you know that Thailand is not in this universe but one where gravity is reversed and water flows uphill.

[mijan24]

Thailand.

International hub of tunnels.

We have the prototype in Khon Kaen an underpass on the main northern highway, from memory the first contractor went bust so the second lucky chappy had to finish off the task.(Still not sure if it was meant to be an underpass or if the second contractor was handed the plans upside down. don't laugh a definate possibility).

Took about 3 years runs underground for about 1 kilometre that includes entry and exit gradients has achieved absolutely nothing. Intersection of Mittarapp (main northern highway) and Maliwan Road which runs from Airport side of town straight through Khon Kaen still grid locks every morning and every evening.(BiB manually operate the traffic lights but must have missed the lecture on "physical traffic control" they work on the principle of Too much traffic, time for coffee and when the daily train at peak traffic times causes a traffic no go East West the BiB manage to also block North South flow with cars who couldn't make the crossing under normal green conditions backing up to prevent any movement - like a three ring circus).

One MP called it an overpass when corrected went on to say "underpass" - "overpass" all the same and moved on in his ramblings of course this wonderful example of Thai Engineering flooded during its first wet season was unpassable all traffic diverted to ring road or side service roads.

It certainly makes one wonder what this two tier drainage tunnel would be like

[ballpoint]

Why all the sarcasm, surely you know that Thailand is not in this universe but one where gravity is reversed and water flows uphill.

Let's keep it simple for the folk of that nature. Take a garden hose. Place one end 2m off the ground, call it "Nakorn Sawan". Place the other end 1m off the ground, call it "sea level". The majority of the hose is below "sea level". Still with me? Now, pour water into the "Nakorn Sawan" end of the hose. Once the hose is full up to "sea level", water will begin to flow out. Amazing! It's flowing 2m downhill and then 1m up hill! Of course, once finished you end up with a hose full of water that needs to be pumped out, but the majority of the water has bypassed the ground between the inlet and outlet, sparing a lot of people from flooding.

Now, as I said in an earlier post, whether it's feasible or not is another story. Pointing out that the principle is sound is in no way agreeing with the proposal.

[anterian]

Why all the sarcasm, surely you know that Thailand is not in this universe but one where gravity is reversed and water flows uphill.

Let's keep it simple for the folk of that nature. Take a garden hose. Place one end 2m off the ground, call it "Nakorn Sawan". Place the other end 1m off the ground, call it "sea level". The majority of the hose is below "sea level". Still with me? Now, pour water into the "Nakorn Sawan" end of the hose. Once the hose is full up to "sea level", water will begin to flow out. Amazing! It's flowing 2m downhill and then 1m up hill! Of course, once finished you end up with a hose full of water that needs to be pumped out, but the majority of the water has bypassed the ground between the inlet and outlet, sparing a lot of people from flooding.

Now, as I said in an earlier post, whether it's feasible or not is another story. Pointing out that the principle is sound is in no way agreeing with the proposal.

Interestingly the Romans never realised this which is why they built many spectacular aqueducts. Incidentally, siphoning water out of a high sided container is another example of water flowing uphill. Water being an incompressible fluid will tend to move from a high pressure to a law pressure zone.

[whybother]

Interestingly the Romans never realised this which is why they built many spectacular aqueducts. Incidentally, siphoning water out of a high sided container is another example of water flowing uphill. Water being an incompressible fluid will tend to move from a high pressure to a law pressure zone.

For the syphon to work you would have to make sure there are no leaks letting air into the tunnels. I think the Romans realised that they couldn't stop the leaks.

[Ricardo]

What's better than starting a multi-billion project that's not even visible at street level?

Perhaps doing an expensive consultancy-study, writing the report & being paid a small-fortune for doing so, and then not bothering to actually build it, so nobody ever knows if the proposal was even worth the paper it was printed-on ?

Clearly a number of 1st-class-flight 5-star-hotel visits, for politicians and civil-servants, to London & Paris (to see the Channel Tunnel) or Japan would be in-order.

Even better, would be to study the option to send the tunnel by long-distance suspension-bridge, and visit San-Francisco or Denmark or anywhere else, where the shopping is good at this time-of-year ?

Edited December 3, 2011 by Ricardo

[anterian]

Interestingly the Romans never realised this which is why they built many spectacular aqueducts. Incidentally, siphoning water out of a high sided container is another example of water flowing uphill. Water being an incompressible fluid will tend to move from a high pressure to a law pressure zone.

For the syphon to work you would have to make sure there are no leaks letting air into the tunnels. I think the Romans realised that they couldn't stop the leaks.

The mechanism of the syphon is not clearly understood, Intuitively an air gap would stop the flow, in fact this is not the case, momentum plus cohesive forces will maintain the flow if the air gap is not too large. Also if the point of leakage is at higher pressure than the outlet, which it will be, the leakage would be water out not air in.

I have established these facts empirically while siphoning many demijohns of wine into bottles, often to the detriment of my kitchen floor.

[ResX]

It would become a stationary collection pond only. it takes gravity to move the water to the sea from rivers etc. One only needs see what happens to sewerage outlets etc....they flow backwards when overflowed at the outlet.

As was so often spoken about, during the high tides, the water could not flow into the sea, it backed up, in fact the reverse happens, the sea raises the level of the river and floods the land.

100km in 2 years.....1 km per week??? 200 billion..... yeah right!! TiT......land of miracles. 1 meter per week and 2000 billion. would be closer to reality!! a fleet of longtail propellors type idea!!! 100% useless.

Someone has not done the sums here, just a mis-informed pie in the sky idea to substantiate someone's job. They need some "real" experienced engineers to draw up a national flood relief plan, and i strongly suspect it wouldnt be Thai engineers. They need an international consortium, Japanese and Dutch maybe? to sort it out, for the future of the country.

If you read the newpapers you will realise that the tunnel is directed to Khlong Dan where pumps will lift the water into the sea. Khlong Dan is where the Airport drainage water pump station is located and also the Industrial Waste Water Treatment Plant for Samut Prakarn.

Having said that, this scheme at B200 Billion, is a waste of money (except to the recipients of the brown envelopes). The floods are caused mainly by excessive monsoon rains falling south of the main reservoirs in the North of Thailand, particularly the Yom River basin. The resulting flow was 5,500cu.m/sec and the Chao Phraya River can only handel 3,000 to 3,500cu.m/sec without flooding occuring. What has always been required is a large bypass waterway from Nakhon Sawan north of the Chao Phraya regulating barrage, to Khlong Dan, in order to handle the excess 2-2,500cu.m/sec, as well as uprating the capacity of the Thai Chin River. This has been proposed for the last 30 years since the first JICA flood Mitigation Study in 1983 approved by the King. Problem is that they only built the Kings Dyke to keep the rich people in the centre dry whilst exacerbating the flooding in the areas North of the King's Dyke which for all intents and purposes is a dam holding back the flood waters. The people in the Water World have been deliberately chosen to be sacrificed for the sake of the Island of inner Bangkok. This current proposal has been reported incorrectly as the depth of cover would be 10metres (not 10kms)due to the road being constructed on top of it. This tunnel is required only for the immediate areas north of Bangkok which were designed as flood plains for growing rice only which would flood during monsoon rains to a depth of up to 2metres deep. Anyone like myself will remember back in 1982 flying into Bangkok's tiny airport over miles of rice paddys with no houses in sight. There should have been no houses or buildings built on the flood plain until the Chao Phraya river bypass had been been built.

You know what you are talking about. For time being before any dam or any mitigation measure is made available, the best way to mitigate floods in Thailand is to develop flood mitigation and control strategy using the existing dams and reservoirs. As far as I can see Thailand has no such thing before the recent floods. It is NOT totally hopeless. As far as I can see the size of the recent flood could have been reduced by at least 40% if three Thailand major dams that I know were well prepared... They are Bhumibol, Sirkit and Chao Pharaya. They are many more dams in Thailand. But I didn't know much details about them.

[cloudhopper]

The mechanism of the syphon is not clearly understood...., Also if the point of leakage is at higher pressure than the outlet, which it will be, the leakage would be water out not air in.

By many perhaps including the professors here, but the physics are straightforward. Why will any leak be at a higher pressure than the outlet? Any leak above the inlet level will destroy the siphon.

[ballpoint]

The mechanism of the syphon is not clearly understood...., Also if the point of leakage is at higher pressure than the outlet, which it will be, the leakage would be water out not air in.

By many perhaps including the professors here, but the physics are straightforward. Why will any leak be at a higher pressure than the outlet? Any leak above the inlet level will destroy the siphon.

They're talking about a tunnel under Bangkok, not a tube in the sky passing over it. Why would they want to make any part of the tunnel higher than the inlet? As long as the entire tunnel is below the level of the inlet, this is not a siphon and has nothing to do with one.

[bino]

This would be a more realistic solution... flood control waterway. This one is in my native Canada, protecting the city of Winnipeg from the Red River. Lots of cities have them... the ones in Los Angeles have been made famous in many movies.

[anterian]

The mechanism of the syphon is not clearly understood...., Also if the point of leakage is at higher pressure than the outlet, which it will be, the leakage would be water out not air in.

By many perhaps including the professors here, but the physics are straightforward. Why will any leak be at a higher pressure than the outlet? Any leak above the inlet level will destroy the siphon.

http://www.straightdope.com/columns/read/2372/how-does-a-siphon-work

http://www.thenakedscientists.com/forum/index.php?topic=17612.0

http://www.guardian.co.uk/science/blog/2010/may/10/dictionary-definition-siphon-wrong

As I said cohesive forces and gravity are the prime causes of the action. As to leaks, the outlet must be at the lowest pressure.

[onionluke]

The mechanism of the syphon is not clearly understood...., Also if the point of leakage is at higher pressure than the outlet, which it will be, the leakage would be water out not air in.

By many perhaps including the professors here, but the physics are straightforward. Why will any leak be at a higher pressure than the outlet? Any leak above the inlet level will destroy the siphon.

http://www.straightd...s-a-siphon-work

http://www.thenakeds...p?topic=17612.0

http://www.guardian....on-siphon-wrong

As I said cohesive forces and gravity are the prime causes of the action. As to leaks, the outlet must be at the lowest pressure.

A big long leaky tunnel ?

[cloudhopper]

As I said cohesive forces and gravity are the prime causes of the action. As to leaks, the outlet must be at the lowest pressure.

The gravitational gradient is virtually the entire driving force, despite the popular articles you quoted. As you noted siphoning wine a small bubble which completely separates the column and therefore all possible cohesive forces will not stop the siphon.

The lowest pressure in a siphon occurs at the highest point, not at the outlet.