Rain exceeded city's drainage capacity

The flooding in inner Bangkok was caused by the sudden deluge of more than 100 millimetres of rain, well above the city's drainage capacity which could handle up to 60mm of rainfall at a time, Bangkok deputy governor Wallop Suwandee said on Wednesday.

He said the city’s drainage system - including water gates, pumping stations and water tunnels - had functioned efficiently.

The BMA had now cleaned out 97% of the city's drains and reduced water levels in canals in preparation for more rain.

Deputy city clerk Jumpol Sampaopon said Bangkok is situated on soft soil and on a low-lying plain. The land  was subsiding at a rate of one centimetre to 10 centimetres each year.

The 100-130mm of rain this month caused a flood five to 20 centimetres deep in some low areas, partly because the influx of rainwater pushed up water levels in the canals and the floodwater on the roads could only drain off slowly.

The BMA will improve the water flow in canals which have only a low degree of slant that means the water runs  out slowly, he said.

Meanwhile, Department of Corrections director-general Suchart Wong-anantchai said his department has 1,000 inmates ready to help dredge canals and clean drains in inner Bangkok to help combat any flooding.

Many main roads in the capital city were flooded on Tuesday after heavy rain, leaving many motorists stranded on roads for hours.  

Pol Col Suchart Wong-anantchai, director-general of Department of Corrections, said the department would survey the spots which were flooded Tuesday to locate the problems.

If the problems were along the 3,500 kilometres of drains which had earlier been dredged, the department would send prison inmates to redo the job.

If the problems were found to be from drainage pipes being too small, the department would inform the Bangkok Metropolitan Administration and the government so they could take action to correct it.

The department had 1,000 inmates ready to help the BMA drain the water during heavy rain.

Pol Col Suchart said prisons nationwide been instructed to select well behaved inmates to perform public services, with a target of a total of 2,000 prisoners on stand by.

Share your thoughts

Discussion 1 : 20/09/2012 at 03:10 PM
97% of the drains cleared huh? They missed the sois around Ratchada so that must be the 3% remaining to be done. I look forward to seeing the action here in the next few weeks. from iPhone application.
Discussion 2 : 20/09/2012 at 03:05 PM
PTP's solution for the flood was to repaved most of the roads so cars can pass when it floods. Amazing solution.
Discussion 3 : 20/09/2012 at 02:27 PM
While we all know that PT are wasting lots of money on flood related matters, it would be really helpful if we can be told if it is a central government or a BMA responsibility to maintain the drains and klongs in Bangkok.
Discussion 4 : 20/09/2012 at 02:18 AM
Diss 4 Upena. I'm sure I have read a BP report quoting more like 300 billion. What amazes me is that out of the 300 billion bht "Flood Budget" you need un-skilled and Free labour from 1,000 inmates instead of hiring or purchasing proper machinery and skilled people to do the job properly. The news and stories here just get more ridiculous by the day!!
Discussion 5 : 20/09/2012 at 01:25 AM
Amazing how it takes so long to conclude the obvious! The only draining that passed quickly without problem was the deluge of cash allocated to fix the (unfixed) problem.
Discussion 6 : 19/09/2012 at 10:16 PM
What can you really do when it`s common knowledge that Bkk is 90cm above sea level and sinking at a rate of "10 millimetres (1cm) per 3 years" ? "The land was subsiding at a rate of one centimetre to 10 centimetres each year". A bit alarmist or what , so he is saying that Bkk will be under water within a decade ? Well then again , they were saying that they wanted to build a new Capital during last years flood ? Just imagin how much taxpayer baht could be snavelled by the usuall 30-50% under the table payments ? Is it worth it ?
Discussion 7 : 19/09/2012 at 08:57 PM
Bangkok always floods when there is a big rain, always has always will. Out in the western suburbs the Ministry of Transportation has just about completed the resurfacing of the outer-ring road. Put down about 100mm of new asphalt but did nothing for the drainage system. In fact I would estimate that more then 80% of the drains have in fact been restricted. Nice job government. I hope the Benz's of the MP's responsible get swamped like everyone else. Shear stupidity that is an everyday thing here.
Discussion 8 : 19/09/2012 at 08:54 PM
The same can be said for the entire country. If the rain exceeds the drainage capacity there will be flooding. Even with improvements the system can only handle so much water. It's a way of life in tropical moonsoon coutries.
Discussion 9 : 19/09/2012 at 08:06 PM
Am I understanding correctly? Inner Bangkok has been flooded? Everybody in government from PM Yingluck, the related government authorities and the scientific/university experts have declared that there wouldn't be any flooding in Bangkok this year. If this is true, when will everyone learn not to make PUBLIC DECLARATIONS... unless they are CERTAIN...of their predictions. Feeble excuses afterwards are not acceptable. Is it true, inner Bangkok is already flooded?
Discussion 10 : 19/09/2012 at 07:49 PM
Excuses, excuses. Where did the 130 billion baht go?
Discussion 11 : 19/09/2012 at 07:04 PM
The population of Bangkok has quadrupled in the last two decades, but its drainage and sewers stay the same. Add this to the slow sinking of the city and these types of floods are inevitable.
Discussion 12 : 19/09/2012 at 06:46 PM
Cleaned? The klong on Sathorn Road was never touched and is full of mud and garbage...
Discussion 13 : 19/09/2012 at 06:21 PM
Even during the dry season the drainage system of Bangkok was already half full (or half empty, depending on who said it).

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