The recent flooding caused 180 deaths in 18 provinces - and 90 per cent were from drowning, permanent secretary for public health Dr Prat Boonyawongvirot said.

The ministry's survey of eight provinces with a total of 120 deaths found the cause most cited was alcohol consumption at 27 per cent, followed by victims slipping into water at 21 per cent. The number of male victims was six times more than female victims and about 55 per cent of those drowned were aged between 31 and 60 years, Prat said.

Death from drowning happened fast, within three to four minutes in fresh water and within seven to eight minutes in salt water.

Prat urged Loy Krathong festival revellers - especially children - to be careful when floating their krathongs in rivers and other flowing water sources, and said water-transport operators should prepare life-saving equipment to prevent further tragedy.

The ministry has ordered hospitals nationwide to be ready for emergencies. People can call 1669 around the clock for help.

In Angthong, four family members drowned before noon after their car plunged into a flooded area.

Captain Paithoon Utama-ampaipong, 52, his son Nithra, 27, a relative Tongta, 45, and grandson Khunnithi Supanoraroj, 3, suffocated after the failure of an electric-window system trapped them inside their submerged car for 20 minutes. Pathoon's daughter Suporn, 23, the sole survivor, said tearfully they had left Bangkok to take necessities to a relative's home in flood-hit Wiset Chai Chan district in Angthong.

The car swerved to avoid hitting a motorcycle that cut in front of them. Paithoon lost control of the vehicle, sending it into a flooded roadside area. "We were struggling for our lives and trying in vain to open the doors for 20 minutes. It was horrible," Suporn said.

Information and Communications Technology Minister Sitthichai Pookaiyaudom visited Angthong's Pa Moke district in the morning to deliver 1,400 relief bags from the private sector to affected residents, while Phra Wisit Khanaporn, deputy head monk for the province, gave Bt10,000 in assistance to 60 flood-hit temples in the province.

As water levels in the Chao Phya River and adjacent flooded areas are falling by about 10 centimetres a day, flood waters at the Muang Angthong municipal market have receded by 80 per cent and many roads have become useable. The situation is expected to be back to normal by Wednesday, officials said.