Advancing pools of filthy water threatened the Thai capital's underground system today and surrounded the emergency headquarters set up to deal with flooding that has claimed more than 500 lives nationwide.
Bangkok Governor Sukhumbhand Paribatra has ordered evacuations in 11 of Bangkok's 50 districts, and partial evacuations apply in seven more, as the huge run-off from monsoon-buffeted central Thailand seeps south through the metropolitan area to the sea.
The evacuations are not mandatory, and most people are staying to protect homes and businesses.
But the orders illustrate how far flooding has progressed into the city and how powerless the government has been to stop it.
The latest district added to list was Chatuchak, home to a large public park and an outdoor shopping zone that is a major tourist attraction.
The Chatuchak Weekend Market was open over the weekend but had fewer-than-normal vendors and customers, as floodwaters poured past the market's eastern edge.
Chatuchak, just a few miles north of Bangkok's still-unaffected central business zone, also is home to the government's national emergency flood relief headquarters.
It is housed in the Energy Ministry - a building now surrounded by water.
The relief headquarters moved several days ago out of Bangkok's Don Muang airport after it, too, was flooded.
Relentless rainfall has pummelled Thailand since late July, swamping the country and killing 506 people, according to the latest government statistics. Most victims have drowned, while a handful died from flood-related electrocutions.
No deaths have been reported in Bangkok. The nearby province of Ayutthaya, which has been submerged for more than one month, has the highest toll with 90 reported dead.
Floodwaters have begun receding in some provinces north of the capital, and a major cleanup is planned in Ayutthaya this week. But water has massed around Bangkok and completely submerged some of the city's outer neighbourhoods.