Floodwaters advanced on central Bangkok Friday, forcing a major department store in the north of the city to shut its doors while authorities struggled to divert the water from the inner city.

The floods caused the closure of the Central Lat Prao store, opposite Chatuchak Park which is famed among tourists for its weekend market.

A sea of flood runoff from Thailand’s swamped central plains has accumulated in northern Bangkok and is slowly making its way to the Gulf of Thailand to the south of the city.

The government has so far succeeded in keeping the floodwaters out of the centre of the capital, where most of the well-known tourist attractions, five-star hotels, shopping malls and upscale residential neighbourhoods are located.

But the city’s northern and north-eastern suburbs have been submerged for weeks, prompting tense showdowns between government authorities who have erected dykes to prevent the runoff from flowing into the inner city, and inundated communities on the other side of those dykes.

Authorities are trying to divert the runoff to flow west and east of Bangkok and then down to the sea.

Parts of the capital are expected to remain under water for weeks, while other neighbourhoods have been kept dry throughout this year’s monsoon season floods, the worst in five decades.

Unusually heavy rains this wet season have triggered floods nationwide since July 25, claiming 442 lives over the past three months and causing damage to crops and industry estimated at 3 to 16 billion dollars.

The Bank of Thailand has lowered its forecast for Thailand’s economic growth from 4.1 per cent to 2.6 per cent because of the floods.

The disaster is expected to also hit Thailand’s tourist arrivals, originally targeted at 19 million visitors for the year.

To date, Bangkok’s Suvarnabhumi International Airport has stayed operational.

“I am confident that we can keep Suvarnabhumi dry,” said Somchai Sawasdeepon, the acting general manager of the airport, 20 kilometres east of the city centre, which has served as the main international airport for Bangkok since 2006.

The capital’s old airport, Don Mueang, 15 kilometres north of the centre, and now used only for some domestic flights, has been closed for weeks with its runway currently under a metre of water.

Suvarnabhumi is protected by a 3.5-metre dyke surrounding the complex, which also includes a system of drainage canals and reservoirs with a storage capacity of 4 million cubic metres.

Mr. Somchai said that passenger traffic had increased 10 per cent in October, boosted mainly by a 14.5-per-cent jump in domestic traffic as citizens fled Bangkok.

International passengers were up 3.5 per cent, but started to fall off in late October.

“After October 24, arrivals from some Asian markets such as China, Japan and India started to decline,” Mr. Somchai said.

During the first nine months, some 14.4 million foreign tourists visited Thailand, up 27 per cent year-on-year, according to the Kasikorn Research Centre, a private think tank.

The kingdom’s tourism sector has been hard hit by a series of natural and man-made disasters over the past decade, including the 2003 SARS scare, the 2004 tsunami, the 2006 coup, followed by months of street protests in Bangkok in each of 2008, 2009 and 2010.

For a week in November-December 2008, Suvarnabhumi Airport was closed to all international flights after the “yellow shirt” protesters seized the airport in their bid to force the government to resign.

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