Chao Phraya'S Great Wall

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SPECIAL REPORT

Chao Phraya's great wall

Pongphon Sarnsamak,

Chularat Saengpassa

From the river's sourse in Nakhon Sawan to its mouth near Bangkok,flood barriers are go upping

BANGKOK: -- Flood barriers - in some spots as high as 5.5 metres - are going up along the Chao Phraya River.

Construction is full steam ahead in many provinces, right up to Nakhon Sawan, where the river starts and where the 2011 flood crisis remains a haunting memory.

After the disaster last year, residents in Nakhon Sawan and all riverside communities feel they must erect high flood barriers to protect themselves the way Bangkok has done.

"I am confident that my area will be able to tackle flood risks well this year," Nakhon Sawan Municipality Mayor Jittakasem Nirojthanarat said, as workers busily reinforced the floodwall structure.

When the river overflowed last year, his municipality succumbed and sustained Bt10 billion in damage. The highest floodwater level was 3.88 metres.

This year, his local administrative body is fiercely determined to protect its area from flooding. Built with a budget of Bt1.1 billion, the high floodwall will run along a 20-km stretch of the Chao Phraya.

Although the whole project is scheduled for completion in 2015, there is a crucial stretch that will be finished in time to protect Nakhon Sawan municipality's most important zone this year.

This stretch runs for about 600 metres from Pom Nueng Community to an ice factory. Construction is expected to be complete at the end of next month.

It is a part of the project's first phase, which will stretch for four kilometres by the end of April next year.

"We intend to protect all 27.8 square kilometres of Nakhon Sawan municipality," Jittakasem said. "For areas that will not get the permanent flood wall this year, we will build them a temporary embankment."

His management has been very efficient. Although the flood wreaked havoc in his area last year, the situation returned to normal quite quickly compared with other areas.

Nakhon Sawan is the province where the Chao Phraya - the major river of Thailand - forms. From here, it stretches for 370 kilometres through nine other provinces, including Bangkok, to the sea.

For Nakhon Sawan residents, the flood season runs from August to October. About 26 billion cubic metres of water is estimated to run through the Chao Phraya in this province each year during this time.

"We are dredging canals to facilitate the flow of water as an extra measure," Jittakasem said.

Suchart Hengakul, a 62-year-old Nakhon Sawan native, did not protest when the mayor and his team came up with the flood-wall plan, even though his house is beyond the reach of its protection.

"Floods may hit my house, but at least someone in the protected economic zone will be able to send food to me during the flooding," Suchart said.

A massive structure is going up in Chai Nat too. The province's Muang, Wat Sing and Manorom districts faced serious flooding last year.

The provincial government has spent about Bt120 million on building a temporary embankment along Phaholyothin Road. It will stretch |for 23.8 km from Chao Phraya |Dam to Muang district's Tambon Tammamoon and Ban Dak Ka Non to the Manorom irrigation project. The dyke's highest level is estimated at about 3 metres above ground level.

The embankment is expected to prevent floodwater from flowing into the city zone.

Kimyan Fhakbua, a 67-year-old small shop owner, said she feared the embankment would keep floodwater in her neighbourhood and leave her house flooded longer than it should be.

In Angthong, about 12km of dyke and floodwall are expected to be built along at-risk areas by the Chao Phraya. The highest section of the wall will be 2.5m above road level.

"Angthong is located on a low plain. If we do not build a flood wall to prevent floodwater, all areas across the province will be submerged by a massive amount of water from the Chao Phraya and Noi rivers," said Chatnarong Siriporn Na Ratchasima, who heads the Angthong Disaster Prevention and Mitigation Office.

In Ayutthaya, the Royal Irrigation Department's Phak Hai Water Distribution Office plans to use seven roads as flood barriers. Once the plan is completed, these roads are expected to contain floodwater in water-retention areas designated in Phak Hai, Bang Ban and Sena districts. These areas form a natural floodplain.

The road surface will be about 5.2 metres above ground level.

Meanwhile, the Transport Ministry plans to raise the level of strategic logistical roads and build a floodwall for a combined stretch of 500km, as well as using barriers to protect the economic zone in Bangkok and nearby provinces.

Thanawat Jarupongsa-kul, a lecturer at Chulalongkorn University's Unit for Disaster and Land Informa-tion Studies, said the flood-prevention measures such as walls and dykes along the Chao Phraya would raise the level of water in the river and cause it to flow more rapidly.

"Before installing flood walls or other embankments along the river, the government should do modelling to study the impact from the construction so they will know where to build and where not to build the floodwalls," he said.

Nakhon Sawan municipality floodwall

TOTAL LENGTH: 20KM

-Total height of floodwall

above the road level:

5.5 meters

- Highest floodwater level in

2011 (above the road level):

3.88 meters

- Highest floodwater level in

2006 (above the road level):

3.33 meters

- Highest floodwater level in

1995 (above the road level):

3.13 meters

-Protected Areas: 27.8 sq km

- Construction cost:

Bt1.1billion

- Scheduled completion: 2015

- The first phase (a 4-km-long stretch) to be completed in April next year

-- The Nation 2012-07-23

[draftvader]

I'm not a fluid dynamics engineer, but the water that isn't being pushed out must go up. All we need to do is see another strong tide pulling the water up the river like happened last year and all they've done is create a giant water feature and create bigger havoc downstream. This does not bode well as it would mean that we would need less water to see more flooding in other areas.

[chotthee]

The next man made marvel. As seen on Discovery Channel.

[Moruya]

It looks like a load of sticks with mud backed up on it. Is that what they are building? Berms?

If the water goes as high as a metre or so above normal, the currents will be much faster and I'm not sure a berm is right for those conditions.

[Sateev]

"From the river's sourse in Nakhon Sawan to its mouth near Bangkok,flood barriers are go upping"

dam_n those non-degreed English teachers!

[jayjayjayjay]

"From the river's sourse in Nakhon Sawan to its mouth near Bangkok,flood barriers are go upping"

dam_n those non-degreed English teachers!

Shouldn't that term be reserved for reporting on drugs "upping"..... !

[Theboy]

No only swan upping

[Arkady]

With all the corruption and incompetence involved I imagine these barriers will end up like the pill boxes made by the corrupt PWD in Hong Kong that vaporised at the first Japanese shell.

[Robby nz]

Wont matter how high they build the barriers if the water cant get out it will go over them.

Last year where I live on the CP River the hight of flood water was about the same on the river wall as the year before.

The difference was that last year it escaped and flooded a part of the other side of the river therefore giving the water an alternate way of getting out.

Had this not happened the water along the wall would have been much highter.

What they are now doing is confining the river between the barriers meaning that it will go a lot highter.

There needs to be another way for the water to get out not to confine it.

[OzMick]

The comparison to the Great Wall is apt - it didn't work either.

[robblok]

If they do it right and make sure the river can't get out of its banks then BKK will have the problem.

[Narratio]

Could it be that's the real plan, to make sure everything hits the Big Mango?

I can see it now, secret midnight up country cabals, plotting thier 'Walls of Vengeance'. Directing every single cubic metre of flood water into Bangkok in revenge for the all the little slights and insults suffered over the years.

Yes, it all makes sense!

[Sateev]

It looks like a load of sticks with mud backed up on it. Is that what they are building? Berms?

If the water goes as high as a metre or so above normal, the currents will be much faster and I'm not sure a berm is right for those conditions.

They did this same type of retaining wall around the little lake in Nong Thin Park in Nong Khai, and then along the Mekong there. They drive prefab cement poles into the mud, then place prefab concrete slats behind the poles and backfill.

I hope the quality of work along the Chao Phaya is better than that at Nong Khai: they beat the snot out of the tops of most pilings, breaking them in the process, and uprooted/damaged all the shade trees along the bank, making a beautiful natural-looking parkland look like a nuclear waste catch basin.

No earthly reason to do it at the park, unless someone's brother-in-law needed the business.

[Moruya]

It looks like a load of sticks with mud backed up on it. Is that what they are building? Berms?

If the water goes as high as a metre or so above normal, the currents will be much faster and I'm not sure a berm is right for those conditions.

They did this same type of retaining wall around the little lake in Nong Thin Park in Nong Khai, and then along the Mekong there. They drive prefab cement poles into the mud, then place prefab concrete slats behind the poles and backfill.

I hope the quality of work along the Chao Phaya is better than that at Nong Khai: they beat the snot out of the tops of most pilings, breaking them in the process, and uprooted/damaged all the shade trees along the bank, making a beautiful natural-looking parkland look like a nuclear waste catch basin.

No earthly reason to do it at the park, unless someone's brother-in-law needed the business.

And no warranty at all I'd wager

[waza]

Great idea, lets hope these wall hold or instead of a flood they will have a tsunmi

[thaibeachlovers]

There's no mention as to whether or not they are providing areas to be flooded ie building the wall on one side only of the river, or as has been pointed out, it will take less water than before to rise higher than before, and probably overflow the wall, no matter how high they build it. Water will go where it will, no matter how clever humans think they are. That's why they need flood plains to take the excess water, but now overpopulation is settling on flood plains there is increasing pressure to erect barriers everywhere. Happens in the UK too.

Remember what happened in New Orleans- the water invaded through the weak links in the chain ( wall ).