Authorities are bracing for overcrowding at major airports across the country during the Songkran festival as passenger traffic is expected to surge past last year's recorded figures.
During the holiday period, airports will be filled with thousands of local and foreign travellers, and authorities are warning passengers that long queues at immigration checkpoints are "unavoidable".
Airport officials estimated the number of international passengers will increase by more than 1.6 million, or 162,000 a day, between April 9 and 18.
"That's a 6.98% rise from last year," said the deputy chief of Immigration Bureau's subdivision 2, Pol Col Choengron Rimphadi on Thursday, before adding this figure also means that the flight numbers will go up by about 7%.
The "Wihok" -- literally, bird -- operation is currently underway until April 18, which is hoped to help expedite document inspection at immigration counters at airports, said Pol Col Choengron.
During the operation, immigration officers have been ordered to speed up their work to ensure that international passengers will not have to wait for more than one hour during "rush hours", he said.
However, he said, long queues are likely to persist at Suvarnabhumi airport, which is located east of Bangkok, as it is a major gateway for travellers flying in and out of Thailand.
Pol Col Choengron also advised passengers to plan ahead, as long queues will not only form at immigration checkpoints, but also on roads leading to major airports across the country.
"Passengers are advised to leave their homes at least three hours before their flights during this period," he said.
Their preparations came after the government announced the beginning of the "seven dangerous days" on Thursday as a part of its bid to curb road accidents during the Thai New Year period, when many people travel across the country to celebrate the holiday.
During the five-day holiday period that begins today, even more personal cars will be travelling along Thai roads. "Their numbers should increase by 3.4%, or about 7.6 million, compared to last year's figures," Transport Minister Arkhom Termpittayapaisith said.
Agencies under his ministry are working with traffic police to ensure motorists adhere to traffic laws during the period.
Meanwhile, The Mass Rapid Transit Authority of Thailand (MRTA), which oversees electric railway projects in Bangkok, will help by re-opening parts of lanes on roads that are currently closed off by construction works.
"Four projects will be temporarily stopped during the holidays -- including works in Saphan Mai, Min Buri and Samrong in neighbouring Samut Prakan," MRTA governor Phakhaphong Sirikantharamat said.
"This will help ease congestion because these sites are located on roads that lead out of the capital."