Bangkok governor MR Sukhumbhand Paribatra blamed widespread flooding and the resulting traffic gridlock on Tuesday to unseasonably heavy rain.
Speaking to reporters today, MR Sukhumbhand said streets flooded because the downpour was unusually strong, falling at up 60-70 millimetres per hour.
The BMA was able to drain the runoff from major streets within two hours, except for Asok Montri Road, where it took three hours. Drainage was slow on the street because the city was holding water in the Saen Saep canal for dry season, when normally there are shortages, the governor said.
In a press conference on Wednesday to explain reasons for the flooding, MR Sukhumbhand said that the rain on Tuesday was unseasonably strong and fell at up to 60-70 millimetres per hour.
- BMA in hot water: Prayut irked by Bangkok flooding
- Gallery: Rain leaves flooding, traffic jams
BMA permanent secretary Sanya Chenimit said Bangkok has more than 1,000 water pumps at 166 stations and can handle rain falling at a maximum 60 millimetres an hour. However, he noted, some pumps were out of service for repairs.
An obviously annoyed Prime Minister Prayut Chan-o-cha said on Wednesday said he had ordered the National Council for Peace and Order and the BMA to explain why the city was so unprepared.
MR Sukhumbhand said other hard-hit areas — such as a basement-level supermarket on Sukhumvit Road and Rama IX Soi 7 — are private property and not the BMA's responsibility, MR Sukhumbhand said. The Tops supermarket was inundated when a sewer pipe back-flushed into below-sea-level store.
The governor promised that the BMA will be more capable of coping with heavy rain when Bangkok's second large drainage tunnel under the Bang Sue canal is completed in September next year.
As for where he was during the flood, MR Sukhumbhand told reporters he couldn't reach the inundated area and, besides, his arrival would have only worsened traffic.
As an executive, his job was to issue orders, not "dredge a canal" himself, he said.