Where will it flood in Bangkok?By Bangkok Pundit Oct 29, 2011 3:20PM UTC
“Flood will hit every area of Bangkok but each area will see the different level of floodwater,” Flood Relief Operation Centre (FROC) director Pol General Pracha Promnok said yesterday. He is also the justice minister.
Sukhumbhand frames it a bit differently as per Bloomberg:
“There is no sign that floods will spread all over Bangkok,” Sukhumbhand told a group of executives yesterday. “The severity of the problem depends on each area.”
BP: In the national address by the prime minister a few nights ago laid out the worst-case scenario as per Bloomberg:
Last night she spelled out a worst-case scenario in a national address, warning that water may “run through the center of Bangkok,” with the severity depending on elevation.
Water levels in parts of Bangkok may reach as high as 1.5 meters (4.9 feet) if a major breach occurs in dikes to the north of the capital, she said, with depths reaching about 50 centimeters in most places, she said. It would take up to a month to drain floodwaters from Bangkok in that case, she said.
Asked today how confident she was that the dikes would hold, Yingluck responded, “50-50.”
She stressed that, as eastern Bangkok is traditionally a flood way for the city, areas such as Meenburi and other eastern districts could see water of as high as one to 1.5 meters.
Residents in the North and West can expect to see 50 centimeters of flood water.
The possibility of inner city Bangkok floods will depend on if flood barriers hold. In the worst case scenario, the prime minister said that business districts would see 10 centimeters to 1.5 meters of water depending on the area. Various areas will not see the same level as some areas are lower than others.
Yingluck admitted that another worrying factor is the rising tide which is affecting the banks of the Chao Phraya River. Riverside communities and roads are the most at risk at this time.
The Cabinet also declared public holidays on October 27, 28, and October 31 which was partly done to allow Bangkokians and those in other flooded areas to leave town as that would make it easier for the authorities to evacuate the remaining people if it was deemed necessary. The key problem is that we are expecting a high tide over the next couple of days.
But the higher-than-normal tides in the Gulf of Thailand, expected to peak Saturday, are obstructing the flood runoff from the north, and there are fears the overflows could swamp parts of downtown. The government also is worried major barriers and dikes could break.
The flood walls protecting much of the inner city are 2.5 meters (8.2 feet) high, and Saturday’s high tide is expected to reach 2.6 meters (8.5 feet).
Friday’s morning high tide passed without a major breach, but the waters briefly touched riverside areas closer to the city’s central business districts of Silom and Sathorn.
“It is clear that although the high tides haven’t reached 2.5 meters, it was high enough to prolong the suffering of those living outside of the flood walls and to threaten those living behind deteriorating walls,” Bangkok Governor Sukhumbhand Paribatra said.
The Chao Phraya river running through the middle of Bangkok broke a record by swelling to 2.47 meters above the mean sea level, or 33 centimeters below the government’s main barriers. It is expected to climb to 2.57 meters later today, the Bangkok Metropolitan Administration said on its website, and Governor Sukhumbhand Paribatra warned communities in 13 districts to watch for flooding. The tide reached 1.28 meters above the mean sea level and may climb to 1.31 meters tomorrow.
AP on the morning high tide:
The complex network of flood defenses erected to shield Thailand’s capital from the country’s worst floods in nearly 60 years was put to the test early Saturday as coastal high tides hit their peak. No major breaches were immediately reported.
Fear gripped Bangkok early in the day as tides along the Gulf of Thailand crested at about 9 a.m. and pushed the city’s main waterway, the Chao Phraya river, to its brink. Overflows so far have lightly inundated riverside streets from Chinatown to the famed Temple of the Emerald Buddha.
BP: Although, a lot of money has been invested in drainage systems for Bangkok over the last 20-30 years so overflows are generally drained quickly, we still have a couple more days of high tides to go.
The two key factors that BP has been able to determine on which areas will flood are whether they are low-lying areas or not and whether they are near the Chao Phraya River and other canals. It is not an exact science. Whether you live near or close to the river and canals is usually fairly obvious, but how do you know whether you live in a low-lying area. The below map from Chulalongkorn University shows the elevation of all the roads in Bangkok:
See this image for a very high resolution and very large (20MB) image file. You can see which parts are low-lying and which are not. These images are in Thai language only so hence also see this below image, in English, to give you a perspective of where things are:
A larger size of this image can be found here. This is an image from the Royal Thai Survey Department – you can view the original Thai image and others from Chulalongkorn here. Many parts of Bangkok are barely above sea level. If you are also near the river or some canals then well it is just a matter of how much water you will get…
Btw, apologies for the lack of links, but no time. Have (for now) limited internet access and trying to finish off some posts started on Wednesday.