Heavy downpours, high tide prompt flood alert in capital
Bangkok has raised its flood alert level with heavy rain expected to fall until Saturday, adding to a huge volume of run-off continuing to flow from upstream and high tide impeding flood water drainage.
All the capital's main canals are full, except for Klong Saen Saep which was almost full as of Thursday, said city governor Chadchart Sittipunt, adding that a trough is expected to bring more rain to the city.
Run-off coming from upstream areas measured as much as 1,850 cubic metres per second Thursday morning, which added more of a burden to attempts to drain excess water from the capital into the sea, he said.
Worse still, all these negative factors coincided with a high tide period which began on Wednesday and is expected to continue until Saturday, he said.
From Wednesday night to Thursday morning, Lat Krabang district reported the most rainfall of 130 millimetres, which triggered flooding in communities near Prawet Buri Rom Canal, the main flood drainage route in eastern Bangkok, he said.
"All the main canals in the city are full, except for Klong Saen Saep which is almost full as well, despite frantic attempts to drain excess water from the city," he said.
One of the problems with the city's drainage system is that old drains aren't capable of accommodating a precipitation level as high as 170mm as experienced in Bang Khen district on Tuesday night, he said.
That explained why Klong Lat Phrao and Khlong Prem Prachakon have been full ever since, he said. Bangkok is literally surrounded by areas with extremely high levels of water in rivers and canals, which are stalling flood water drainage from the capital, he said.