Oral Reply by Ms Grace Fu, Minister for Sustainability and the Environment, to Parliamentary Questions on Flooding
Mr Seah Kian Peng: To ask the Minister for Sustainability and the Environment (a) whether the Ministry has conducted a comprehensive review of areas that are susceptible to flash flood situations like what was experienced on the morning of Friday 20 August 2021; and (b) what plans are being made to mitigate such possibilities from recurring going forward.
Ms Hazel Poa: To ask the Minister for Sustainability and the Environment whether he can provide an update on the flood management measures and early warning system in view of the recent flooding.
Mr Desmond Choo: To ask the Minister for Sustainability and the Environment in view of the recent incidents of flooding and forecast of inclement weather due to the Indian Ocean Dipole over the next two months, what are the Ministry's plans to mitigate against flooding, especially in areas where there are major roadworks.
1 The effects of climate change are being increasingly felt around the world. Recently, we saw widespread flooding caused by record rainfall in parts of Europe, China and the USA.
2 Singapore has also experienced intense rainfall events in recent months. On 17 April and 24 August, more than an entire month's rainfall fell on our western parts within three to four hours. Given climate change, we must prepare for more extreme weather scenarios as we are likely to see more flash floods from intense rain.
3 PUB has invested almost $2 billion on drainage works in the last decade, and reduced Singapore's flood prone areas from 3,200 hectares in the 1970s to 28 hectares today. PUB will continue to monitor these flood prone areas closely. Another $1.4 billion will be invested over the next five years on drainage improvement works. It is, however, not practical to expand all 8,000 plus kilometres of our drains and flood protection infrastructure to accommodate every extreme rainfall event, as this would require massive land take and much higher costs.
4 Flash floods arising from intense rainfall occur in limited areas and are transient - most will subside within 30 minutes, given our extensive drainage system. Moreover, PUB deploys immediate and practical measures to protect our properties against flash floods, including portable flood barriers that can be installed at doorways or erected on roads and pavements. These flood barriers protect residents and businesses against flash floods and minimise potential damage to their premises.
5 PUB is using technology to better predict and respond to floods. PUB will complete enhancements to its rainfall forecasting capability by 1Q2022. This will help forecast locations which will face heavy rainfall, issue earlier public alerts and enable early deployment of portable flood barriers in areas at risk of flash floods. Coupled with an extensive network of water level sensors and CCTVs installed at flood prone areas, PUB's Quick Response Team will be deployed on site faster, and assist premises owners to set up flood barriers if required. Information on floods and road closures are communicated to the public promptly through radio broadcasts, news media, myENV Mobile App, PUB Facebook and Twitter, as well as LTA's Expressway Monitoring Advisory System. SMS alerts are also sent to those who have registered to receive flood warnings.
6 These measures will also help build preparedness to extreme weather events and strengthen community resilience, as we check weather advisories and warnings and adjust our daily schedules accordingly. I encourage members of the public to subscribe to NEA's and PUB's SMS alerts.
7 PUB will continue to strengthen our forecasting and sensing capabilities and implement cost-effective measures to minimise flood risks. However, PUB cannot minimise flood risks on its own. Building owners must ensure that flood prevention measures in their developments remain effective. Contractors must also implement proper flood prevention measures at their worksites. We have seen cases of contractors failing to do so, resulting in floods in their locations.
Flash flood on 20 August 2021
8 This brings me to the flash flood incident that occurred on 20 August 2021. This flash flood was reported at the junction of Tampines Ave 10 and Pasir Ris Drive 12 towards TPE entrance at around 8.00am. PUB's Quick Response Team was immediately deployed to assist drivers and pedestrians, together with SCDF and the Police. PUB also issued advisories to motorists and members of the public to avoid the area.
9 This location is not a flood prone area, and the drainage system is more than adequate to cope with the rainfall intensity experienced on 20 August 2021. PUB's investigations found that the contractor carrying out road widening works along Tampines Avenue 10 had altered the public drainage system there without approval. As a result, stormwater could not discharge effectively into downstream Sungei Api Api. PUB does not condone such illegal works and will be pressing charges against the contractor under the Sewerage and Drainage Act.
10 Under the Sewerage and Drainage Act, no one can carry out any works to alter our storm water drainage system without PUB's approval. PUB also requires contractors working in the vicinity of any watercourse to put in place measures to prevent construction materials from falling and choking up the drainage system. PUB takes a serious view of all works that affect our public drainage system. We have reminded all contractors to comply with the requirements and will take enforcement action against errant contractors.