In mid-August Prime Ministry Prayut Chan-o-cha promised that flood water flowing from the North would not overflow downstream provinces in the Central Plains.
But on Tuesday he explained he was doing everything possible, even though the weather insists on raining.
"The government is doing everything it can to manage the water, but in some areas it is flooding because of heavy rain and because other areas are low-lying," he said
Also on Tuesday, Deputy Bangkok governor Amorn Kitchawengkul met the directors of five district offices in northern Bangkok -- Don Muang, Sai Mai, Laksi, Chatuchak and Bang Khen -- to discuss ways to cope with flood problems in these areas.
The five districts have experienced heavy rain over the past week. Floods in the areas can only be drained into the Premprachakorn canal. But the canal is now filled to capacity and canal water cannot be drained out to the Chao Phraya River, Mr Amorn said.
On Oct 1, rainfall on Chaeng Watthana Road in Laksi district was measured at 144mm -- the highest ever recorded in Laksi district.
Adisak Khantee, a former director of the department of drainage and sewerage under the Bangkok Metropolitan Administration (BMA), explained why the BMA's existing giant drainage tunnel under Rama IX Road had failed to ease flooding for the whole of Bangkok.
The tunnel has a drainage capacity of 60 cubic metres per second and cannot handle excessive floodwater caused by heavy rains, he said.
Next year, another drainage tunnel will be open under the Bang Sue canal, which will help improve flood drainage in Bangkok, Mr Adisak said.