To keep floods at bay as Singapore is lashed by increasingly intense storms, the country is pumping another $500 million into a massive upgrade of its drainage network.
National water agency PUB said yesterday the money will be channelled into ongoing projects at 75 spots islandwide, as well as those at 16 new locations and future projects, to make monsoon drains and canals bigger, and fortify older structures, for instance.
Said Mr Ridzuan Ismail, PUB’s director of catchment and waterways: “With climate change, we expect more intense storms to occur more frequently in Singapore. PUB will continue to implement ‘pathway’ (the passage that rainwater takes) measures by deepening and widening drains.”
The sum, which will be spent over the next two to three years, adds to the $1.2 billion the Government has already spent on drainage improvement works since 2011.
Meteorological Service Singapore statistics show that the annual maximum hourly rainfall rose to 90mm last year, from about 80mm in 1980.
“We are right to ‘buy insurance’, to put these plans in place and execute them, so we are not caught unprepared,” said weather researcher Koh Tieh Yong from the Singapore University of Social Sciences.
There have been floods on 14 days this year, compared with 10 last year, and six in 2015. The figure has, however, dropped from 36 in 2013.
Drains in flood-prone areas or those nearing the end of their lifespans will be given priority in upgrading. Next year, they will be improved in areas such as Thomson Road and Sennett Estate.
The 3.2km Bukit Timah First Diversion Canal will be expanded by the end of next year at a cost of $280 million. It will be able to take in 30 per cent more rainwater.
This will protect buildings in the catchment area, such as Ngee Ann Polytechnic, Beauty World Plaza, Bukit Timah Shopping Centre and Sime Darby Centre, from floods.
The project, first expected to be ready by last year, has been delayed by the difficult terrain, said PUB.
Expansion works are also ongoing at Sungei Pandan Kechil, Bedok Canal and Kallang River.
Drain works at the 75 locations are expected to be completed over the next two to three years, adding to the upgrading of drains and canals at 325 locations since 2012.
To help protect Singapore’s shopping belt from floods, such as those that washed through Orchard Road in 2010, are projects such as the Stamford Diversion Canal and Stamford Detention Tank, which are almost complete.
The diversion canal, which will relieve Stamford Canal of a portion of water, is set to be completed by the third quarter of next year. The tank will hold water temporarily – enough to fill 15 Olympic-size pools – so that less water gushes into Stamford Canal during heavy rain. It will be completed by the middle of next year, and PUB will be testing its pumps this month.
While the drains undergo their overhaul, PUB stressed that further upstream, developers too must play their part.
Mr Ridzuan said due to competing demands for land use, there is a limit to how big and wide drains can be. “A more sustainable approach is a collective effort involving developers to put in measures to slow down run-off into public drains and to protect developments from floods.”