The Land Transport Authority (LTA) is increasing flood prevention measures at MRT stations.
It called a tender to enhance flood prevention measures at 11 MRT stations, several months after it did the same for six stations in the central area.
The 11 stations up for this round of enhancement works are: Braddell, Toa Payoh, Boon Keng, Somerset, Outram, Tiong Bahru, Bugis, Lavender, Bishan, Marina Bay and Changi Airport.
The works will include installing flood-barrier systems at the stations, sealing glass panels and other openings to make them watertight, and raising escape staircases, reported The Straits Times.
Two types of flood-barrier systems are expected to be installed at several points in each station - a manual stackable type and a swing-type which stays open during normal times.
Tender documents state that flood barriers should be made of lightweight aluminium panels and be designed to be watertight when flood waters are below 1.5m.
A spokesman for the authority told the paper: "All MRT stations and associated structures... were designed such that the entrance and crest levels are high enough to accommodate potential flooding in lower lying areas."
While no MRT station has ever been flooded, these will serve as additional preventive measures as these stations are located in low-lying areas with track records of flash-floods.
The earlier project was awarded to Sigma Builders for $2,228,776 to enhance six stations: Orchard, City Hall, Raffles Place, Tanjong Pagar, Novena and Little India.
Work on the first six stations will be completed by the middle of next year, while the next 11 stations should be outfitted by the third quarter of 2014.
Assistant professor Vivien Chua, who teaches in the Department of Civil and Environmental Engineering at the National University of Singapore, told the paper that temporary flood barrier systems are more reliable in holding back floodwater compared to sandbags, and are also cost-effective solutions compared to the economic cost of flood damage.