Bangkok Governor Aswin Kwanmuang will be remembered as someone who has been quite active in implementing flood prevention measures.
Regardless of the questionable outcome, the BMA under his tenure has invested a fortune in flood draining infrastructure.
Among his pet projects is the construction of "water banks" -- large underground concrete pools to absorb floodwater. They are regarded as the centrepiece of the "Now!" blueprint of his tenure.
The idea stems from the kaem ling water management theory of storing resources for later usage. The term kaem ling (which means "monkey cheek" in Thai) was coined by the late King Rama IX, who noted a monkey's tendency to save the edible flesh of bananas in its cheeks to eat later.
King Rama IX introduced kaem ling to facilitate better water management during both the rainy and dry seasons. He explained that natural water-retention areas in Bangkok had been replaced by houses and buildings, resulting in more floods.
One legacy of the project in Bangkok at that time was Bueng Rama IX Pond. In 1989, King Rama IX instructed City Hall to install aerators he invented in the pond to treat wastewater discharged from Khlong Lat Phrao Canal. In 1992, he suggested the BMA turn this 53-rai natural pond into a flood-absorbing lake.
The BMA has developed several more kaem ling in recent years, for instance, Bueng Nong Bon adjacent to King Rama IX Park, which has become a recreational centre where members of the public can take part in activities such as sailing and boat rowing.
It also serves as a wastewater treatment site, receiving discharge from households and buildings in that area, and a water retention site to ease flood problems.
The BMA later committed to expanding the concept to similar ponds across the city.
Unfortunately, this pledge has translated into barely any action.
A prime example is the 2012 plan to build six kaem ling in the upper and eastern parts of the city, covering about 1,000 rai of land.
However, four of the six drainage basins in Bangkok did not materialise as the designated area had been sold for real estate and commercial purposes.
In 2017, the BMA made an unsuccessful bid to expropriate the land but its owners turned down the offer, preferring to continue to use it for commercial purposes.
The result is that there are only two kaem ling -- the "Bueng Khubon Flood Catchment" in Kannayao district and the "Bang Chan Flood Catchment" in Min Buri district.
For the Bueng Khubon Flood Catchment project, a private firm also turned a 30-rai land plot in the designated water retention site into a commercial complex, which adversely affected the city's flood mitigation measures.
Yet city officials seem unconcerned by the lack of progress in this effective method of water retention and have instead chosen to focus is on costly headline-grabbing projects such as water tunnels and an underground water bank.
Solving the persistent flooding in Bangkok requires a holistic approach, not only investment in technology and fancy infrastructure.
As well as putting money into building effective flood draining systems, the BMA should work faster and harder to acquire land plots to create more kaem ling to ensure a more sustainable water management system in the capital.