Thailand's Capital Bangkok Is Sinking

[webfact]

Thailand's capital Bangkok is sinking

Thailand's capital of Bangkok is under threat of inundation -- being underwater -- within a century, and researchers warn that current flood prevention measures in the city are not ready to prevent such a happening.

The prediction comes from research study calculations indicating that land in Bangkok on average subsides about one centimetre annually.

The study is a cooperative project on geodynamics called 'Geodetic Earth Observation Technologies for Thailand: Environmental Change Detection and Investigation' -- GEO2TECDI -- between Thai-based and European Union institutes.

The cooperation aims to increase skills and Thai-EU joint research capabilities of Thai researchers in applying and exploiting three space geodetic techniques, namely Global Navigation Satellite System (GNSS), Interferometric Synthetic Aperture Radar (InSAR) and Satellite Altimetry (SALT), for the detection, observation and modelling of the change and movement of the tectonic plates beneath Thailand, Bangkok’s land subsidence, and sea level changes in the Gulf of Thailand.

According to Chulalongkorn University's Survey Engineering Department, data from satellites 15 years ago indicated that the earth's tectonic plates have lifted up slowly. But the big earthquakes in Indonesia's Sumatra Island in 2004 which caused the Andaman Sea tsunami quickly resulted in a shrinkage of the tectonics of around 1 centimetre annually, while the subsidence of soil layers for the past decade in Bangkok and its vicinity has continued to subside -- data which matched that of the Royal Thai Survey Department.

Despite such statistics, researchers have not yet determined conclusively when the Thai capital will enter its critical stage of moving into a waterworld. The second phase of research is yet to be conducted to create a model for an accurate forecast.

According to current estimates, the land beneath the Thai capital can sink to as low as sea level in a hundred years when comparing land subsidence ratio to Bangkok's ground, which now is only on average one metre above sea level. Land on the banks of the Chao Phraya River will be the first to be affected.

"The ground level is very low in Bangkok, and some areas are only a few centimetres above the mean sea level, which means that all factors seem to join forces to negatively affect us. The sea level is rising quickly. The level of soil and sand subsides, and the tectonics shrink. All this is worrying," said Assoc Prof Itthi Trisirisatayawong of Chulalongkorn University’s Survey Engineering Department.

Also, Thailand's capital may sink faster than we now expect, for the sea level in the Gulf of Thailand is continually rising, which is also shown by data of the Hydrographic Department dating back some 30 years, demonstrating that the sea level in the Gulf has continually risen around 4 millimetres per year. The accelerating factors for the increasing sea level include global warming causing glaciers to melt and the enlargement of the oceans.

Hydro and Agro Informatics Institute director Royol Chitradon said that the pattern of air flow and of currents in the ocean has changed, which also generates higher waves.

"Currents at the South Pole can create high waves of over 10 metres, which is almost as high as waves in a tsunami. Now the currents at both the North and the South Poles are very strong, and they result in higher waves in the Gulf of Thailand and the Andaman Sea," said Royol, the director.

Some experts believe that Thailand's City of Angels might even sink within half a decade coming up when the ratio of land subsidence is calculated with the annual rising sea level and the outcome compared to the ability of Bangkok's flood prevention and mitigation system.

If no solution is discovered soon, we may have to migrate to other parts of the country so as to make sure our children will stay on solid ground when the capital finally becomes a part of the ocean. (MCOT online news)

-- TNA 2010-07-23

[liveinlos]

How many of us will be around in a century to care?

Next story please

[ajarnchompoo]

OK, fair comment, but what about your kids, and your friends kids and grandchildren............... they are the ones who will be the one to lose out on life as we know it now.

[Wozzit]

This is anything but news. I wonder ho much money has been wasted on this study. I remember another study almost 30 years ago which came up with exactly the same findings!

Get out the lifebelts and flee to the hills!

[JimSiam]

Thailand's City of Angels Mermaids.

Klong san sab is always faster to get down town than a taxi, there is a plus side into a Venice style Bangkok.

Oh, isnt the CAT building with all the internet feeds for Thailand right on the river edge?

[RickBradford]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

[surayu]

Aye Aye Captain !

[MJP]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Agree with the groundwater abstraction bit, but other structures aside, the skyscrapers are (I hope) founded on piles driven to the bedrock so should have no ground pressure on the silt strata above.

[zzaa09]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Continuing to encase the metropolitan area in concrete is not helping, to be sure. The destruction of the natural drain-off is key.

[catmac]

But surely this is all because of Global Warming, isn't it? Well, I'm sure that JR (and his many nom de plumes) would have us believe that that is the case!

[Pib]

Time for the government to start building berms and installing pumps, but I'm sure the government will appoint many committees over many years to evaluate and recommend. Thailand can't do anything without going the slow committee route which hides/blurs/spreads (saves face) if things go wrong...no sir, you can't have single person responsibility for something. Berms and pumps work good until that BIG typhoon/hurricane overwhelms them if not built to handle the every 500 year storm--just ask New Orleans. And just think of the jobs created for the dirt truck haulers in building the berms---more dirt trucks on the road...just what Thailand needs.

Edited July 23, 2010 by Pib

[zzaa09]

Time to move Bangkok to Vientiane.

[trogers]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Agree with the groundwater abstraction bit, but other structures aside, the skyscrapers are (I hope) founded on piles driven to the bedrock so should have no ground pressure on the silt strata above.

The sinking is not the silt strata (1-18m deep). It is the dewatering by 100-150m deep bored wells. The tallest high-rises in Bangkok are supported by piles less than 70m deep and are sinking with the rest of Bangkok.

[Wozzit]

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

The problem is that the Netherlands has spent countless billions of dollars on massive sea defences and inland dykes and raised canals. Where is Thailand going to get that sort of money?

But surely this is all because of Global Warming, isn't it? Well, I'm sure that JR (and his many nom de plumes) would have us believe that that is the case!

It may be, but 30 years ago the theory was the sinking was due in large part to the klongs having mostly been turned into highways. I'm not sure why, but I do recall reading that. Before then, I believe Bangkok was sometimes called the Venice of the East.

[MJP]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Agree with the groundwater abstraction bit, but other structures aside, the skyscrapers are (I hope) founded on piles driven to the bedrock so should have no ground pressure on the silt strata above.

The sinking is not the silt strata (1-18m deep). It is the dewatering by 100-150m deep bored wells. The tallest high-rises in Bangkok are supported by piles less than 70m deep and are sinking with the rest of Bangkok.

Yee gawds! Where's the bedrock?

[trogers]

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Agree with the groundwater abstraction bit, but other structures aside, the skyscrapers are (I hope) founded on piles driven to the bedrock so should have no ground pressure on the silt strata above.

The sinking is not the silt strata (1-18m deep). It is the dewatering by 100-150m deep bored wells. The tallest high-rises in Bangkok are supported by piles less than 70m deep and are sinking with the rest of Bangkok.

Yee gawds! Where's the bedrock?

Bangkok is no Manhattan...

It is the site of an ancient river delta, built up from layers upon layers of sedimentary soil. There are 3 main firm layers building piles are seated on - 22-26m, 34-36m and 62-68m.

Edited July 23, 2010 by trogers

[MJP]

 

It's been known for many years that Bangkok is sinking - what do you expect if you build massive skyscrapers on river silt while at the same time extracting the groundwater from underneath?

The change is fairly gradual; the city will have to adapt -- some parts of the Netherlands are meters below sea level and are perfectly viable.

Agree with the groundwater abstraction bit, but other structures aside, the skyscrapers are (I hope) founded on piles driven to the bedrock so should have no ground pressure on the silt strata above.

The sinking is not the silt strata (1-18m deep). It is the dewatering by 100-150m deep bored wells. The tallest high-rises in Bangkok are supported by piles less than 70m deep and are sinking with the rest of Bangkok.

Yee gawds! Where's the bedrock?

Bangkok is no Manhattan...

It is the site of an ancient river delta, built up from layers upon layers of sedimentary soil. There are 3 main firm layers building piles are seated on - 22-26m, 34-36m and 62-68m.

Oh, this doesn't look good at all.  

So, cessation of dewatering should reduce the rate of subsidence or will it eliminate it?

Could be a plan to either put a reservoir (I think there is one?) in fed from upcountry or a desalination plant.

[trogers]

 

Oh, this doesn't look good at all.  

So, cessation of dewatering should reduce the rate of subsidence or will it eliminate it?

Could be a plan to either put a reservoir (I think there is one?) in fed from upcountry or a desalination plant.

Much like deforestation, some locals like making profit from nature. Deep wells provide a source of cheap water, either for bottling and sell or for business use, eg. turkish massage palours.

[David Barker]

Piles do not normally go down to bedrock the design of piles is based on the coefficient of friction on the side of the piles it is possible to increase the number but make piles shorter to have the same friction.

The South tower on the Humber bridge in the UK is actally a hollow pile that floats in the silt strata.

[MJP]

Piles do not normally go down to bedrock the design of piles is based on the coefficient of friction on the side of the piles it is possible to increase the number but make piles shorter to have the same friction.

The South tower on the Humber bridge in the UK is actally a hollow pile that floats in the silt strata.

I only used to dig the things up from tank bases and demo jobs and do a bit of sheet piling for cut off walls.

Although I understand the friction bit (soil mechanics was a lot of what I used to do) I'm still surprised they only go down 70m on those skyscrapers though. Learn something new everyday on these forums. 

[MJP]

 

Oh, this doesn't look good at all.  

So, cessation of dewatering should reduce the rate of subsidence or will it eliminate it?

Could be a plan to either put a reservoir (I think there is one?) in fed from upcountry or a desalination plant.

Much like deforestation, some locals like making profit from nature. Deep wells provide a source of cheap water, either for bottling and sell or for business use, eg. turkish massage palours.

Put 2 and 2 together now. What are the soils like at 150m? I've had some nightmarish dewatering jobs in finer silts for enabling works.

[trogers]

Piles do not normally go down to bedrock the design of piles is based on the coefficient of friction on the side of the piles it is possible to increase the number but make piles shorter to have the same friction.

The South tower on the Humber bridge in the UK is actally a hollow pile that floats in the silt strata.

I only used to dig the things up from tank bases and demo jobs and do a bit of sheet piling for cut off walls.

Although I understand the friction bit (soil mechanics was a lot of what I used to do) I'm still surprised they only go down 70m on those skyscrapers though. Learn something new everyday on these forums. 

Did two 8 upper floor condos (plus 1 basement) in the last 5 years. The one in Sukhumvit has 23m deep piles and the other near Soi Aree has 33m deep piles. So soil conditions do vary within Bangkok.

The 60+ storey State Tower (at Bangrak) has piles down into the 60+m depth, with end grouting.

Designers here do not like pure friction piles on soft clay due to the possibility of liquefaction from earth tremors.

[MJP]

Piles do not normally go down to bedrock the design of piles is based on the coefficient of friction on the side of the piles it is possible to increase the number but make piles shorter to have the same friction.

The South tower on the Humber bridge in the UK is actally a hollow pile that floats in the silt strata.

I only used to dig the things up from tank bases and demo jobs and do a bit of sheet piling for cut off walls.

Although I understand the friction bit (soil mechanics was a lot of what I used to do) I'm still surprised they only go down 70m on those skyscrapers though. Learn something new everyday on these forums. 

Did two 8 upper floor condos (plus 1 basement) in the last 5 years. The one in Sukhumvit has 23m deep piles and the other near Soi Aree has 33m deep piles. So soil conditions do vary within Bangkok.

The 60+ storey State Tower (at Bangrak) has piles down into the 60+m depth, with end grouting.

Designers here do not like pure friction piles on soft clay due to the possibility of liquefaction from earth tremors.

Yeah of course you still do get tremors here.

Stockpiling wet materials (silty clays and the best was zinc/lead baghouse dust) really demonstrates the effect of liquefaction. I was trying to get stockpiles of this wet baghouse dust (40,000 cubic metres of it) to stack up to about 6 metres in these bays once. Nightmare, goes from a semi-cohesive material with relatively low slump to a complete slop in seconds. 

[Rinrada]

Time to sell the House...

[dumball]

Somehow , I have a feeling in my water , that there was an article some whiles ago , it said that parts of BKK were already below the level of the river , it spoke of raising the height of the dykes and putting in more efficient pumps , never heard or read anything on the progress of these plans since . The ground subsistance due to the pumping of ground water , has already caused a couple of shop house to lean at a precarious angle , does no-one take note of these occurances in government ?

Also of note , a certain well known and respected proffessor stated , that the rising of the sea level would not effect Thailand as it is too far away from the melting polar ice , whilst a private individual had done his own survey by measuring the loss of land that had succumed to the rising levels of the sea .

Not my problem , I already moved away from BKK .

[HAL9000]

Oh nonsense!

Just make it the "Venice of the Orient".

Think what that would do for tourism!

[bolx]

How many of us will be around in a century to care?

Next story please

Exactly the attitude that has ruined this planet for future generations.... MUPPET

[samtam]

Despite such statistics, researchers have not yet determined conclusively when the Thai capital will enter its critical stage of moving into a waterworld. The second phase of research is yet to be conducted to create a model for an accurate forecast.

This second stage will involve several members of Chulalongkorn University's Engineering Department going out into the street and finding that they are neck deep in muddy water...

[frankman]

And they are still building

and drilling wells

and still selling condos... 

[robint]

Oh No

not another blow to tourism

Tourists will get their feet wet

Panic Stations

Orange alert

With all that flooding they will compensate by growing 3 crops of rice per year

Good idea

up to you

my pen rye