Over the next five years, water agency PUB will be spending S$750 million to improve the capacity of Singapore’s drains by 30 to 40 per cent.
More resources will be put into retaining rainfall upstream to reduce the speed at which water flows into the drains.
Earlier this month, a panel of experts had recommended better ways to deal with increasingly intense rainfall.
On Monday, PUB said it has accepted these recommendations and laid out a comprehensive plan to tackle the problem.
This includes setting aside S$750 million to increase drainage capacity particularly at six major canals such as Geylang River and Rochor Canal.
More importantly, there will be measures such as water retention ponds and rooftop tanks to contain water in localised areas.
PUB will also come up with new flood protection guidelines for buildings within a year.
It said this approach is in recognition that Singapore has to move beyond widening drains and building flood barriers to resolve its flood problem.
One reason is that with land being a premium, there is a limit as to how much can be set aside for drains.
The panel also recommended better data. The PUB said it will be piloting a system over the next two years to better forecast where and when floods will occur.
They will be getting information on rainfall from the Metereological Service and data from their own canal sensors. PUB is not, at this point, able to say how much advance warning it can give but it said that even a few minutes will be helpful to the public.
As for Stamford Canal, in the immediate term, PUB will be coating its walls with a polymer lining to reduce friction and increase water speed. It will also remove the sewer and new water pipes that are placed inside the canal to allow the canal to hold more water.
These measures will raise capacity by about 10 per cent but in the long-term, measures such as a detention pond and diversionary canals are being studied.
