Bangkok is on heightened alert for potential flooding as high sea levels threaten low-lying areas along the Chao Phraya River through to Sunday.

The Bangkok Metropolitan Administration (BMA) is coordinating with other agencies to monitor the situation closely and issue warnings when necessary, the Drainage and Sewerage Department said.

The high tides have prompted daily inspections of flood barriers and drainage infrastructure in the river and the connected canals, namely Khlong Bangkok Noi, Khlong Mahasawt and Khlong Phrakhanong.

Bangkok's permanent floodwalls range from 2.8 to 3.5 metres above mean sea level, but 32 sections, known as "gapped barriers", remain incomplete.

These total 4.35 kilometres and are being temporarily reinforced with sandbags to mitigate flood risks, the department said.

So far, 21 permanent barrier sections totalling 2.58km have been completed in key locations, such as Si Phraya Pier in Bang Rak and Riverside Condo in Bang Kho Laem.

Four additional segments, including areas in Yannawa, Khlong Toei, and Bang Phlat, are under construction and are expected to be finished before the October flood season.