The Thai government says it is taking steps to prevent a repeat of last year’s massive flooding. But experts warn that some of the government’s big ideas – such as large-scale new dikes – probably won’t be completed before seasonal rains arrive in just a few months.

Unusually heavy monsoonal rains in 2011 caused the worst inundations in Thailand in half a century. The floods killed hundreds of people, swamped industrial estates, and caused billions of dollars of economic damage. In a note sent to clients earlier this week, economists at Goldman Sachs warned of the risk that some companies might relocate from Thailand if the floods recur.

With the next annual monsoon season expected to begin roughly in May, the government has put forth several flood prevention proposals, including some $11 billion of water management projects it says should help reduce the risks of a repeat. The efforts include steps to clear clogged canals, strengthen existing flood barriers and create new basins for runoff. It also includes some major construction projects to build new reservoirs and erect new dykes.

Moreover, the government says it has created a new “single command water management organization, chaired by Prime Minister Yingluck Shinawatra, that will organize flood prevention across agencies such as the Bangkok Metropolitan Association and the Royal Irrigation Department. Backers of the plan believe it would help streamline flood control and prevent some of the disputes between government offices that experts say exacerbated flood-management problems last year. A recent government statement said authorities also expect to hold a “major flood drill in August to test preparedness.

Meanwhile, the Industrial Estate Authority of Thailand has reportedly suggested the government give grants and loans to private companies to build flood walls around the industrial estates that were hit last year. Precise funding and legal details, however, are still unclear.

Most recently and perhaps most ambitiously the government said it aims to build a nearly 200-mile-long series of flood walls along a vulnerable stretch of Thailand’s main Chao Phraya river. The barriers would run from the central Thailand province of Uthai Thani south to the city of Ayutthaya. But many experts and residents question whether such floodwalls could be built in time for this year’s rains.

Dr. Seree Supharatid, director of the Disaster Warning Centre at Thailand’s Rangsit University and a member of the government’s Strategic Committee for Water Resources Management, confirmed the plan and its objectives in an interview with Southeast Asia Real Time. But he said that it would be “difficult to complete such a system before the rainy season starts. “Nobody can guarantee the project’s completion date, he said. One variable in the plan is that some of the barriers would be temporary ones built by people in the local communities presumably at different times, not permanent structures erected all at once by the government.

Dr. Ruth Banomyong, an infrastructure expert at Bangkok’s Thammasat University, said he doubted that such a massive project could take shape quickly.

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