A young couple scour a jobs board in the Thai city of Ayutthaya in a desperate hunt for work, more than a month after the factories where they worked were flooded.

They say they are willing to do any work, but with major industrial areas still submerged in Thailand's worst flooding in half a century, vacancies are scarce.

Huge swathes of central Thailand were left under water for weeks when severe monsoon rains caused massive deluges -- ruining crops, closing thousands of factories and swamping millions of homes.

Hundreds of thousands of people were put out of work when the floodwaters swept into key industrial estates in Ayutthaya, 80 kilometres (50 miles) north of Bangkok, and in the outskirts of the capital.

While many factories continue to pay wages and others handed out lump sums when they let staff go, some workers are facing acute financial worries.

"I haven't had any of my salary because I started work just two days before the floods," said Supranee Kongsomkaew at the Ayutthaya employment office.

The 23-year-old said she will probably have to wait until factories dry out before she will be able to find work.

Ayutthaya's Rojana Industrial Park, where thousands are employed by a host of international auto and electronic firms including Hitachi, Honda and Sanyo, is still deluged.

The water level was around half a metre (1.5 feet) on Thursday, down from nearly three metres in mid-October. But the waters are not expected to clear until early December, two months after the site first flooded.

Thailand's economy is predicted to take a major hit as a result of the flooding, with the growth forecast for 2011 recently revised down to 1.5 percent, from 3.5-4.0 percent.

Exports have taken a hit and tourism has also suffered as visitors are put off by dramatic images of buildings and temples marooned in vast pools of water.

Thanawat Poliwichai, director of the Economic and Business Forecasting centre at the University of the Thai Chamber of Commerce, estimates the cost to the economy will be up to 450 billion baht ($14 billion), mostly in the industrial sector.

The bill for property damage could run to $22 billion, he said.

"The damage is not just limited to this year. It will continue to cost next year as well because factories will not be able to resume production until probably February," he told AFP.

Thailand's floods have also had global effects, disrupting world production of everything from cars to computers.

Honda said it still cannot properly assess the damage to its Rojana plant, which employs 4,000 people. Aerial footage from the site shows hundreds of rusting cars covered up to their roofs by filthy water.

Hideto Maehara, of Asian Honda, said the company welcomed Thai government assurances that there will be no repeat of the disaster, but said the firm was considering the wisdom of producing key parts in one place.

"Is it better to spread out production sites and make parts locally in various countries, or to continue to concentrate our production sites and export from there? We will have to engage in further discussions," he said.

Industry minister Wannarat Channukul said the government planned to exempt replacement machinery and raw materials from import duty to ease the pain for businesses.

The floods have posed huge challenges for multinationals such as Honda, but for smaller firms the road to recovery is likely to be even harder.

Workers at the Solar Power Technology plant on an industrial estate on the edge of Bangkok hoisted valuable hardware off the ground before the floods hit.

But the water rose several feet higher than expected, lifting machines off their stands and leaving them strewn and broken across the floor.

General manager Boriwat Chim Charee said damage to equipment alone will cost 30 million baht and only new machines were insured.

But he said the firm has rented another factory to fulfil urgent orders and he was determined to restore the plant as soon as possible.

"We have already sent our people to Japan to buy new machines," he told AFP.

Economist Thanawat said the recovery of smaller firms would depend on the speed at which banks release loans and support measures come into force.

But even in the midst of the disaster, opportunity presents itself for those with entrepreneurial spirit.

In the areas around Bangkok's second airport Don Mueang, the only way to traverse the stagnant green waters of flooded streets is by boat.

One man told AFP that when the floods came and his regular work in construction disappeared, he got a boat and set up a water taxi service -- and business is brisk.