THAILAND will not see a replay of the Great Flood of 2011 this year because the level of rainfall and others factors are different – in fact hydrologists are warning that water might even be in short supply during the next dry season.

“We have to understand that we are in a total different situation than 2011. That year we faced five storms inbound for Thailand,” Royon Jitdon, director of the Hydro and Agro Informatics Institute, said last week.

“We also received a tremendous amount of precipitation almost all year, which filled all major dams by the middle of the rainy season.”

Since this year’s flood season is now in full swing and as of Friday, 17 (out of 77) provinces across the country had reports of flooding, many people are worrying that devastating floods will strike again, as happened five years ago.

However, the specialists, who took part in flood mitigation back in those days, stressed that water situations in 2011 and this year are different.

According to the Irrigation Department’s records, rainfall in 2011 averaged 1.95 metres, compared to 1.24 metres this year up to September.

There was as much as 70 billion cubic metres of water in all reservoirs across the country was and this filled all of the major dams in the Chao Phraya River basin rapidly.

“We’re talking about a whole different volume of water that we’re facing this year, from back in 2011,” Royon said.

Chaowalit Chantararat, managing director of the TEAM Group, said the water volume back in 2011 was too much to manage.

“At that time we faced a serious water management problem because all major dams were full and urgently needed to discharge water,” he said.

“But downstream was already swamped with water as well, so the existing floodwaters combined with the dam discharge caused the historic flood. The only strategy we could use that time was to drain the water to the sea as fast as we could and a major flood was inevitable.”

Seree Supharatid, director of Rangsit University’s Centre of Climate Change and Disasters, said there was no way this year’s flooding would match what occurred in 2011, as the situation was totally different and the flooding now has come mainly from rain, not the dams like five years ago.

“I think that the South should be warned of major floods more than the Central Plain, as the prediction is for heavy rain and possible storms in the South,” Seree said.

Chaowalit pointed out that water mismanagement was another factor that worsened the flood situation in 2011.

“There was a severe drought in the dry season of 2010-11, so the water policy of that year was to store more water for the next dry season and the policymakers did not think that there would be so much rainfall during that year,” he said.

“We just realised this when there was already flooding downstream and the dams were full,” he said.

Royon said the major weakness of water management was that policy-makers often managed the water situation based on fear of flood or drought.

“We have to manage water based on scientific data and predictions,” he said. “We should plan water management by considering the real-time water situation, the scientific prediction for the next two weeks and the rain pattern of next year.

“We already have big lessons from the big flood of 2011 and major drought of 2015. We should not repeat the same mistake.”

Despite the flood in Central Plain this year, he suggested that the water should be stored for the next dry season rathen than wastefully discharged to the sea, because the country just passed through two years of serious drought and there was not much collected in the major dams.

“The rain pattern for this year and next year was predicted to be at the normal rate, but considering the water storage in the major dams, we should spare the water supply for the dry season and we should release water with care,” he said.

Chaowalit also noted that Bhumibol Dam was still at less than half of capacity. “We should manage the water carefully for the upcoming dry season,” he said.