I am very impressed by the credentials of all the top drainage experts in town and their fanciful solutions to the ponding problems in Orchard Road. I think they will work, if not, just at a few more measures as things go along. It just costs a little more money that’s all.
I am no expert in any of these stuff, drainage, catchment area, water flow, rate of flow, porous material, drain capacity, and building ponds on roof tops. Hopefully they don’t burst or the flats do not collapse with the additional weight.
Looking at the big picture, my first layman impression is that the Marina Bay Reservoir has raised the water level in the city catchment area. All the drains and canals are perpetually full, or filled to a much higher level and capacity. As such, any sudden downpour will only raise the water level and add to the water already in the catchment area, canals and drains. And they will overflow very quickly. You don’t need a thunder storm that pour in a year’s rainfall in half an hour. Just get the city folks to pee into the drain and you will get ponding immediately.
Maybe, if they have not done so, try to lower the water level of Marina Bay Reservoir by a meter, if that is feasible, and live with it for a while to see how much more pondings will occur. It is not going to cost any money, or very little money. Just a small experiment before they go along with all the great and fanciful recommendations and infrastructure works which may not work. But they will certainly create a lot of jobs and employment and raise the GDP or National Productivity to a higher level.
This is really a two cent worth comment. Sometimes, when a person is having obese problems, there is no need to go on a specialist circuit to pay for all the expensive tests, advices and treatment when all it needs is a little dieting. Please laugh at it if you want. I am no expert and my credential is that of Emperor of Cyberspace, and my forte is to blog on controversies.