Giant drains ‘will not prevent floods’

By Chularat Saengpassa 
The Nation 

 

File photo :Big Tunnel

 

Academic urges BMA to make it mandatory for big condo, office building projects to build underground water banks

 

EVEN with 20 giant drainage tunnels, Bangkok will never be safe from floods, predicts a respected university lecturer. 

 

Thanawat Jarupongsakul, who teaches at Chulalongkorn University’s Department of Geology, made this prediction when the city administration began touting these structures as a way to improve the capital’s flood problems. 

 

The city’s administration has already built four giant tunnels at great cost, and there are four others under construction and at least one more being proposed. 

 

“I personally think these tunnels are a waste of money,” Thanawat said, adding that not only did they cost a lot to build, maintenance costs were also very high. 

 

Thanawat

 

He pointed out that Bangkok was sinking, which means the level of the Chao Phraya is rising higher than the city’s canals and its drainage system. 

 

“This means you have to use pumps to push the water into the river, but when these devices break down, Bangkok can get easily submerged,” he said. 

 

On June 7, several parts of Bangkok were under water after just a few hours of rain, leaving many Bangkokians stranded in nightmarish traffic for hours and prompting them to lambaste the Bangkok Metropolitan Administration (BMA). 

 

The city authorities later admitted that there had been some hiccups with an overwhelmed fuse, which disrupted the operations of the Bang Sue Tunnel.

 

 

 “Water from these tunnels has to be pushed high so it can flow into canals and then it has to be pushed even higher so it can flow into the river. It’s a difficult task,” Thanawat said. 

 

 

He also said this drainage system was implemented several decades ago and many of the pipes must be clogged. 

 

“Also you can’t expect this system to handle 60 millimetres of rainfall, when just 40mm to 50mm of rain floods the capital,” he said, adding that Bangkok’s urban expansion was also the cause of growing flood risks. 

 

Bangkok residents use up to 6 million cubic metres of water daily and the wastewater from one big condo project in the heart of the capital is enough to fill up a canal, he said, adding “so when it rains, the city’s canals can be overwhelmed easily”. Instead, he suggested, the BMA should follow Shanghai’s system of requiring that all big buildings construct an underground water bank. 

 

Former Bangkok Governor MR Sukhumbhand Paripatra

 

This way, wastewater can be kept underneath the building and released gradually,” he said. 

 

Visnu Charoen, a senior official at the BMA Drainage and Sewerage Department, said some BMA facilities have underground water banks, like the one along the Srinakharin-Krungthep Kreeta Road, which can hold about 10,000 cubic metres of water. There is also one at the mouth of Soi Suttiporn on Din Daeng Road, which can handle up to 1,200 cubic metres. However, Thanawat said, these water banks were not enough to deal with the flood risks. 

 

 

Confessing that the BMA still hasn’t made it mandatory for the private sector to build underground water banks, Visnu added, “we will offer incentives if they agree to prepare areas for water retention”.

 

 

Professor Suchatvee Suwansawat, president of the Council of Engineers, said underground water banks would be an innovative flood-prevention solution, and that a couple can be developed right away around the big pond in the compound of the Tobacco Thailand Authority and the Chatuchak Park. 

 

 

“These should help ease flooding in Lat Phrao, Bang Sue, Vibhavadi-Rangsit, Ramkhamhaeng and Sukhumvit,” he continued. 

 

Suchatvee also recommended the use of sensor technology to monitor the state of pumps and water jets.

 

Thanawat, meanwhile, suggested that canals and waterways be dredged and pumps installed at the mouth of canals to push water into the river as a short-term measure. For the medium term, he said the size of the drainage pipes should be enlarged. 

 

“For the long term, the government should make it mandatory for all condo projects to build water banks and if possible, Bangkok residents should be charged for water draining,” the academic said. 

 

He added that water-drainage fees will possibly encourage people to save water, thus cutting down on the water to be drained. 

 

For now though, Visnu said the BMA was doing its best to keep Bangkok dry by dredging waterways, cleaning drainage pipes and enlarging them where possible. He also pointed out that floods have been draining away more quickly over the past few years. 

 

“We can’t say drainage tunnels will prevent floods, but at least the water is drained away more quickly,” he said. 

 

-- © Copyright The Nation 2019-06-17

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A lot of what this bloke says makes sense, looks like he is an actual expert in the field. An unfortunately rare occurrence.

i pity him trying to be heard in the places that count.

The magic mantra for the moment is...maintenance....maintenance....and regularly before it breaks down, as that's what maintenance aims to avoid.

1 hour ago, webfact said:

The city authorities later admitted that there had been some hiccups with an overwhelmed fuse, which disrupted the operations of the Bang Sue Tunnel.

Interesting non-technical description there.

Goodness a Thai academic who nearly understands. Perhaps these "brains" of Thailand will eventually understand that the rate at which Bangkok is sinking combined with the rising sea level will be an even greater influence on Bangkok become flooded, then these civil engineering drainage gimmicks that don't actual work.

10 minutes ago, geoffbezoz said:

Goodness a Thai academic who nearly understands. Perhaps these "brains" of Thailand will eventually understand that the rate at which Bangkok is sinking combined with the rising sea level will be an even greater influence on Bangkok become flooded, then these civil engineering drainage gimmicks that don't actual work.

Sadly, he appears a lone voice against the selfish corporate interest of developers in Bangkok.

7 minutes ago, bluesofa said:

Sadly, he appears a lone voice against the selfish corporate interest of developers in Bangkok.

So was King Canute ????????

40 minutes ago, geoffbezoz said:

48 minutes ago, bluesofa said:

Sadly, he appears a lone voice against the selfish corporate interest of developers in Bangkok.

So was King Canute ????????

Although the sea is shared theme, yes, he's likely to be ignore just the same, but for different reasons. Is Thanawat really as raving as Canute?

The current underground drainage tunnels in BKK are amazing....some even flow uphill!

4 hours ago, webfact said:

Bangkok residents should be charged for water draining,” the academic said. 

 

So should they also be compensated every time it floods then ??

An article from four years ago about Bangkok sinking, by the government at the time:

https://weather.com/science/environment/news/bangkok-sinking-subsidence-warming-15-years

1 hour ago, geoffbezoz said:

So was King Canute ????????

I believe Canute was surrounded by yes men and he did his stunt to prove that he couldn't hold back the tide.

11 minutes ago, cornishcarlos said:

 

So should they also be compensated every time it floods then ??

No. They should understand that when it rains it floods and traffic should be managed when it does flood by diverting people around it.

As far as I can see the only solution is to lower the sea level a few metres. This would require a barrier from Pattaya to Hua Hin. The trapped water could then be drained and the situation of excess water easily managed.

 

I don't hold with the idea that all the buildings in BKK be lifted up by 10 metres. Far too costly and technically difficult and would also take too long.

 

The obvious plan, politically, is to move all government and public structures to another area. Udon Thani has been mooted in the past.

Edited June 17, 20197 yr by owl sees all

at least the new elevated trains will run on time. 

2 minutes ago, NCC1701A said:

at least the new elevated trains will run on time. 

Maybe they could replace the submarines when they become flooded/submerged!

34 minutes ago, owl sees all said:

As far as I can see the only solution is to lower the sea level a few metres. This would require a barrier from Pattaya to Hua Hin. The trapped water could then be drained and the situation of excess water easily managed.

 

I don't hold with the idea that all the buildings in BKK be lifted up by 10 metres. Far too costly and technically difficult and would also take too long.

 

The obvious plan, politically, is to move all government and public structures to another area. Udon Thani has been mooted in the past.

How come you have gained access to this secret plan to lower the sea level - who do you know in the government here?

I'm all for moving everything to Udon, my wife can make loadsa dosh buying land before they get here. What time will they be leaving?

How can a condo build a water tank underneath it ?  It needs that piece of land for the building to sit on and for piling.  Try and find any piece of land in Bangkok where you could build huge water retaining tanks. The guy is dreaming about an unworkable idea,

5 hours ago, webfact said:

wastewater from one big condo project in the heart of the capital is enough to fill up a canal

That explains the odour of the canal waters!

7 minutes ago, bluesofa said:

How come you have gained access to this secret plan to lower the sea level - who do you know in the government here?

I'm all for moving everything to Udon, my wife can make loadsa dosh buying land before they get here. What time will they be leaving?

I suggest relocating the capital to Chiang Mai - two reasons:  1.  Higher elevation and 2.  Centralising pollution!

19 minutes ago, bluesofa said:

How come you have gained access to this secret plan to lower the sea level - who do you know in the government here?

I'm all for moving everything to Udon, my wife can make loadsa dosh buying land before they get here. What time will they be leaving?

So long as the lady boys go South to Pattaya when they move, we already have enough of them in Udon already and I think Central Plaza is now fully staffed ????

25 minutes ago, jaiyen said:

How can a condo build a water tank underneath it ?  It needs that piece of land for the building to sit on and for piling.  Try and find any piece of land in Bangkok where you could build huge water retaining tanks. The guy is dreaming about an unworkable idea,

Quite.

 

And a situation that hadn't occurred to him. In all the underground systems that I have studied, the fish that gradually inhabit these underground reservoirs, gradually  become blind (I'll get the link and post it ASAP).

 

I also take the idea that pumps can lift as much as 1000m3 a second, with a pinch of salt. That's like filling/emptying an Olympic size swimming pool in under 2 seconds.

 

Edited June 17, 20197 yr by owl sees all

5 minutes ago, owl sees all said:

Quite.

 

And a situation that hadn't occurred to him. In all the underground systems that I have studied, the fish that gradually inhabit these underground reservoirs, gradually  become blind (I'll get the link and post it ASAP).

 

I also take the idea that pumps can lift as much as 1000m3 a second. That's like filling an Olympic size swimming pool in under 2 seconds.

Blind fish? will there be guide dogs with aqualungs to help them?

Filling an Olympic size swimming pool in under two seconds. For this it only needs five taxi drivers pissing into it - like they do on the side of the road.

31 minutes ago, bluesofa said:

How come you have gained access to this secret plan to lower the sea level - who do you know in the government here?

I'm all for moving everything to Udon, my wife can make loadsa dosh buying land before they get here. What time will they be leaving?

Ah yes!! Wouldn't you like to know?! Well i'll give you a hint,,,,,,.

 

Suffice it to say that this bar girl, I once was friends with, had a pal in the government's, 20 year plan for Thailand, department (water section).

 

I've already put my dosh down. Glad you are thinking positively. Get on board this money-spinner before the rise in prices spike beyond our reach. And, just to add that there is a direct correlation between the sinking of BKK to the rise in land prices in Udon province.

2 minutes ago, owl sees all said:

Ah yes!! Wouldn't you like to know?! Well i'll give you a hint,,,,,,.

 

Suffice it to say that this bar girl, I once was friends with, had a pal in the government's, 20 year plan for Thailand, department (water section).

 

I've already put my dosh down. Glad you are thinking positively. Get on board this money-spinner before the rise in prices spike beyond our reach. And, just to add that there is a direct correlation between the sinking of BKK to the rise in land prices in Udon province.

A twenty year plan by the government? I bet most disbelievers had eyes as wide as your bar girl friend's legs.

 

So the lower the land sinks in Bangkok, the higher the Udon land price.

I do remember now, it's called Somchai's law, showing how one is inversely proportional to the other.

 

2 minutes ago, bluesofa said:

A twenty year plan by the government? I bet most disbelievers had eyes as wide as your bar girl friend's legs.

 

So the lower the land sinks in Bangkok, the higher the Udon land price.

I do remember now, it's called Somchai's law, showing how one is inversely proportional to the other.

 

Very droll Bluesofa.

 

You are not without a hint of humour and I like that in a poster. But on a serious note; this bar girl I once knew has moved on to better and bigger things. In fact she is making me a cup of Rosy right now.

 

And as for your mathematical suggestions, you are nearly there, except that it's; one mm of BKK sinking = 10% rise in Udon land prices.

I must take some pics of the drains being put into a road near us, been going on for months. The drains themselves are in concrete blocks, but are all 18 inches to two feet above the road surface. Everyone is watching to see if they will be ripped out again or the road raised up, if they did that all the businesses would be inaccessible.

Politicians know that water flows from north to south. It was a problem in Western Australia too...

 

looks like a recipe for sinkholes 

2 hours ago, jaiyen said:

How can a condo build a water tank underneath it ?  It needs that piece of land for the building to sit on and for piling. 

See schematic - shows tank being fed by two buildings lies below an adjacent or nearby open space area suggesting a public park.

But I doubt there's enough current open spaces and potential areas for open spaces in Bangkok that can handle all the necessary water tank storage areas for all its buildings.