|- Localised topographic characteristics|
| ||Localised depressions on the roads and on the ground are naturally prone to water accumulation. In low-lying areas, options to reduce flooding are sometimes limited because the deepening of drains, especially those leading to the sea, would need to tie in with downstream levels.|
|- Clogged drainage systems|
| ||Drains can get choked with leaves, litter and other debris that get washed into them during storms.|
10. Can we solve the flood problem by widening and deepening drains and canals?
While flooding cannot be completely prevented, it can be alleviated with continual drainage improvement. Widening and deepening of drains and canals, and road raising are some ways of improving drainage.
In low-lying areas, however, drainage improvement projects are effective only if the surrounding ground level is also raised. Such projects will be carried out when the area is redeveloped. For existing older roads which are relatively low-lying and flood-prone, the road levels would be raised either in conjunction with drainage upgrading works or LTA’s road upgrading works as part of PUB’s plan to reduce flood-prone areas wherever possible.
11. How does Marina Barrage help in flood alleviation?
The Marina Barrage is a dam built across the Marina Channel to keep seawater out. It is part of a comprehensive flood control scheme to alleviate flooding in the low-lying areas in the city such as Chinatown, Boat Quay, Jalan Besar and Geylang. During heavy rain and low sea tide, the crest gates at the dam will be activated to release excess storm water into the sea. When the sea tide is high, giant pumps that are capable of pumping an Olympic-size swimming pool per minute, will drain excess storm water into the sea.
Click here to find out more about the Marina Barrage.
12. Are the recent floods due to the increased urbanization in Singapore?
Prior to any new land development or before construction begins in any area, PUB works together with agencies such as URA, HDB, LTA and JTC to map out necessary drainage measures.
13. What is PUB doing to alleviate floods?
PUB has a Flood Management Strategy to manage flood risks in Singapore. These include providing adequate drainage ahead of new developments; implementing flood protection measures; and continual drainage improvement in flood prone areas.
Click here to find out more about flood management strategies.
14. Is climate change a contributing factor to the recent floods?
In 2011, the Expert Panel on Drainage Design and Flood Protection Measures conducted a six-month review on flood protection and risk management measures that will be implemented in Singapore over the next decade. The experts noted that, based on the rainfall intensity records over the past 30 years, there is strong evidence of a trend towards higher rainfall intensities and frequency of intense rains. These up-trends are consistent with the Inter-governmental Panel on Climate Change 4th Assessment Report (IPCC AR4) and could add further strain on Singapore’s existing drainage infrastructure. PUB has put in place a multi-pronged plan that covers the entire spectrum of drainage and flood management. This includes implementing higher drainage design standards and holistic solutions, building new capabilities and working with stakeholders to improve preparedness. Through these efforts, we seek to minimise and mitigate the impact of flash floods in Singapore.
Click here to find out more about the key conclusions and recommendations of the Expert Panel.
15. Did poor maintenance contribute to floods?
To keep our drains free-flowing and able to perform to their designated capacities, PUB adopts a multi-barrier approach to trapping litter and litter collection as part of its litter management. Contractors are deployed island-wide to carry out physical cleansing, maintenance and minor structural repairs of drains and canals.
A new Department of Public Cleanliness (DPC) has been set up within the National Environment Agency, aimed at improving operational efficiency by integrating the cleaning functions of public areas (including the cleansing of drains, canals and waterways) by various agencies. This will be done in phases from April 1, 2012. In the long run, this will allow the DPC to better manage cleaning contracts, improve service standards and enhance responsiveness to public feedback. Choked drains, canals and dirty waterways will limit drainage capacity and prevent fast and effective drainage during heavy rain. Therefore everyone can do their part in keeping our waterways clean and litter free. If you see any choked drains or pollution in the waterways or reservoirs, you can call the PUB 24-hour Call Centre at 1800-2846600 or call DPC hotline at 1800-600-3333 or email email@example.com to report.
Click here for more information on drainage maintenance.
16. Can PUB inform the public of floods or potential floods?
The public can access PUB’s Facebook and Twitter accounts for the latest update on flash floods. They can also call the PUB 24-hour Call Centre at 1800-284 6600 and tune in to the radio for the latest news.
As part of its monitoring system, PUB has installed 163 sensors in key canals and drains to track the water levels. The public is able to access information on the water levels in the canals either through PUB’s dedicated flash flood management website, an SMS alert service or PUB’s free iPhone app “MyWaters”.
Click here for more information on Water Level Sensors and CCTV images.
Click here for more information on subscribing to SMS alerts.
Click here to go to PUB’s official Facebook Page.
Click here to go to PUB’s official Twitter page.
17. Why are there floods after the completion of the Marina Barrage?
The recent flooding incidents in Orchard Road (June 2010) and Cuscaden/Tomlinson Roads (June 2011) were due to the exceptional storms.
The Marina Barrage is part of a comprehensive flood control scheme to alleviate flooding in the low-lying areas in the city such as Chinatown, Boat Quay, Jalan Besar and Geylang. By removing tidal influence, the five rivers (Stamford Canal, Rochor Canal, Kallang River, Singapore River and Geylang River) are safe from back-flow of water as the water level within the Marina Reservoir can be kept constant or lowered when there is impeding storms.
By keeping seawater out, Marina Barrage acts as a tidal barrier to reduce flash floods in low-lying areas in the city. Its nine crest gates will be lowered if there is excess water in the basin. In the event that heavy rains coincide with high tides, seven drainage pumps will be activated to remove excess storm water in the basin.
18. How can I get weather information?
NEA provides weather information and updates on their website (Weather@SG, rain animation, etc), through their Twitter account (@NEAsg) and their iPhone application (“myENV”). The public can now subscribe to heavy rain warning SMS alerts as well.
Click here to visit their website here for more details.
Click here to subscribe to the heavy rain warning SMS alerts.
19. Is PUB providing further flood protection for the Orchard Road area?
PUB has completed the raising of Orchard Road (from Orange Grove Road to Cairnhill Road) in 2011. It has also announced plans to increase the flood protection for the Stamford Canal catchment (which includes the Orchard Road area) by constructing a detention tank and diversion canal.
Click here for more information on enhancing flood protection for the Stamford Canal catchment.
20. What additional flood protection measures is PUB adopting to deal with the more intense storms?
To provide additional flood protection measures, PUB has in place a Code of Practice on Surface Water Drainage that stipulates drainage requirements. This includes minimum platform and crest levels for buildings and entrances to underground facilities (e.g. basement carparks, underground MRT stations, etc). The latest revision in December 2011 entailed raising the stipulated minimum height of platform, land reclamation and crest levels for new developments to provide better flood protection for buildings. The design parameters for new drains were also enhanced to cater to more intense rain storms.