It accepts expert panel's recommendations, will take steps to tackle floods
By Feng Zengkun, The Straits Times, 31 Jan 2012
NATIONAL water agency PUB has accepted the recommendations of an expert panel to tackle floods and will roll out a slew of measures in the next five years.
These include short-term engineering solutions such as increasing Stamford Canal's flow capacity by 10 per cent within a year to reduce floods in the prime Orchard area.
PUB, which announced the measures yesterday, will also spend $750 million over the next five years on 20 drainage projects. It will deepen and widen six other major canals, in places such as Bukit Timah, Geylang and Bedok, to increase their capacity by 30 to 45 per cent.
The panel of foreign and local experts, appointed by the Government last June after a spate of floods here, released its recommendations earlier this month.
The panel of foreign and local experts, appointed by the Government last June after a spate of floods here, released its recommendations earlier this month.
It said PUB would need to implement a range of solutions at buildings and along pathways to handle more intense storms and mitigate the effects of increased urbanisation.
PUB should also review its drainage-system planning guidelines as well as improve its flood-warning system, the panel added.
It noted that more data on rainfall patterns and how rain water flows across the land would need to be collected.
PUB chief executive Chew Men Leong yesterday called the new moves 'a multi-pronged plan... to minimise and mitigate the impact of flash floods in Singapore'.
Besides engineering solutions, the agency will also improve flood-prediction and warning systems, such as posting closed-circuit television images of flood-prone areas on its website from March.
By year end, the National Environment Agency (NEA) will roll out an improved heavy-rain alert system.
PUB will also create digital land height maps of the major catchment areas by next year to be used in a new flood-prediction model by 2014.
In Orchard Road, hit by three floods in the past two years, PUB will smoothen the walls of Stamford Canal between Cuscaden and Grange roads to speed up water flow. Pipes in the canal will be removed to increase its capacity.
These projects will be completed within a year.
In Orchard Road, hit by three floods in the past two years, PUB will smoothen the walls of Stamford Canal between Cuscaden and Grange roads to speed up water flow. Pipes in the canal will be removed to increase its capacity.
These projects will be completed within a year.
The agency will decide by May whether to build a diversion canal or water-storage pond or both to ease the canal's burden in the long term. Minister for the Environment and Water Resources Vivian Balakrishnan had said in Parliament earlier this month that the canal would divert rain water to the Singapore River, and the pond would be about the size of two to three football fields.
Other engineering solutions include fresh guidelines for new buildings by the year end.
These may include green roofs that can help slow and retain rain water, and flood barriers at buildings in low-lying areas. The agency said it would consider making the guidelines mandatory in high-risk places and may work with building managers to retrofit existing structures.
In the long term, PUB will update its drainage masterplan every three years, compared with every five years now. This will help the agency keep on top of weather changes and make adjustments or interventions, or change drainage-design standards, said Rear-Admiral (NS) Chew. PUB will publish the masterplan next year.
He added that an inter-agency committee convened in 2010 to tackle floods, comprising PUB, the Housing Board, Singapore Land Authority, Land Transport Authority, Building and Construction Authority, National Parks Board and industrial landlord JTC Corporation, will continue to work on the new measures together.
Head of the expert panel Chan Eng Soon said the agency's solutions are in line with the panel's recommendations. 'These are significant commitments and I am glad to note the emphasis on a holistic approach that covers the entire drainage system in each of the catchments,' he added.
But Mr Chik Hai Lam, building supervisor of Liat Towers which has been hard-hit by floods three times, said increasing Stamford Canal's capacity may not be enough.
PUB has to take care 'of the debris in the canal as well. We went into the canal to have a look ourselves, and there was so much debris - sand, branches', he added.
What PUB will do to fight floods
IN THE SHORT TERM
Increase Stamford Canal's flow capacity by 10 per cent within a year to reduce floods in Orchard Road
Set up fresh flood prevention and alleviation guidelines for new buildings, which may include roofs with plants to slow and retain rain water and flood barriers at buildings
Set up fresh flood prevention and alleviation guidelines for new buildings, which may include roofs with plants to slow and retain rain water and flood barriers at buildings
Make available closed-circuit television images of flood-prone areas on the PUB's website from March
Roll out an improved heavy-rain alert system by year end. This will be undertaken by the National Environment Agency
IN THE MID TERM
Launch a new flood-prediction model by 2014, which will take into account cloud patterns, rainfall and water levels; digital maps will predict where rain water will flow
IN THE LONG TERM
Expand six major canals in places such as Bukit Timah, Bedok and Geylang, to increase their capacity by 30 to 45 per cent in the next five years
Build a diversion canal or water-storage pond to ease Stamford Canal's burden. The PUB will decide which measure to adopt by May
Review drainage masterplan every three years instead of every five, as is being done now. The PUB will publish a masterplan next year
Singapore 'must broaden flood-risk calculations'
By Grace Chua, The Straits Times, 1 Feb 2012
By Grace Chua, The Straits Times, 1 Feb 2012
THE price tag from flood damage in June and July 2010 was $23 million.
That was the tally from 868 insurance claims for business interruptions, property damage and motor vehicle damage, a government-appointed panel of experts said in its technical report on flood prevention.
The report, published on Monday, urged that Singapore broaden its risk management calculus to take such damage and other factors into account when planning drainage systems.
At the moment, drainage planning here takes into account only the size of each catchment and the type of installations, such as MRT stations, on the land.
But many things contribute to the risks posed by flooding. The frequency, duration and magnitude of floods all play a part, as do their consequences: How long will it take and how much will it cost to clean up afterwards? What vital infrastructure stands in the way of the inundation, and to what extent will traffic and the economy be disrupted?
The panel's technical report said: 'High risk can occur either from frequent floods that have relatively limited consequences (as in the case of the 2010 and 2011 flood events in Singapore), or from rare floods that have great consequences (such as the 2005 flooding in New Orleans).'
Already, countries such as the United States, Australia and the Netherlands use the more comprehensive risk management approach. By using this approach, the panel said, the potential of solving a flood problem in one location and creating flooding elsewhere can be avoided. It is also a cost-effective way to prioritise spending.
But weighing and computing the various flood-risk components is easier said than done, said National University of Singapore civil engineering associate professor Vladan Babovic. Prof Babovic, who was not involved in the panel, said the value of tangible assets like property is easy to calculate, but intangibles are less easy to put a price tag on.
'If you have a flooded park, that is not very nice, but what is the value in monetary terms?' he said. 'Those intangible assets need to be valued.'
Other intangibles, the panel's report said, might include the impact of floods on reputation or effects on health.
Prof Babovic noted that the rapid changes in storm frequency, intensity and duration make floods even more difficult to predict.
To address this, planners use a variety of scenarios, which give a range of outcomes. And when building drainage infrastructure, planners could reserve some physical space to increase the capacity of canals, for instance.
Prof Babovic and colleagues at Singapore-Delft Water Alliance are helping develop analytical tools to help planners work out the trade-offs between reserving such flexibility, building a high-capacity canal immediately and building something else.
Canal works: Expect traffic diversions
Some of the projects involve drains under roads being widened
By Feng Zengkun, The Straits Times, 1 Feb 2012Some of the projects involve drains under roads being widened
DRIVERS in parts of Singapore could face up to a year of traffic diversions because of work to expand several major canals.
National water agency PUB said yesterday that projects at Bukit Timah, River Valley, Geylang and Rochor will involve drains under roads being widened and deepened.
Diversions and traffic snarls could last from six months to a year for the smaller drains.
On Monday, the agency announced it will expand six canals as part of its plan to reduce floods. The other two are in Bedok and Kallang.
PUB said it will carry out the work in stages to keep disruption to a minimum.
If there are separate projects taking place in the area, it will cooperate with the other authorities to make sure that the public suffers as little inconvenience as possible.
In Rochor, for example, part of the canal expansion will be near work on the Downtown MRT Line.
PUB said the canal work will be split in two, with the Land Transport Authority leading the expansion of the canal stretch near the line.
This will allow both projects to be coordinated more efficiently.
The agency added that 'during the work period, roads and pedestrian pathways will remain accessible and businesses and traffic can continue as usual'.
But engineers told The Straits Times that the canals go through old, built-up estates. Given the scope of the expansions, some disruption to businesses and residents will be unavoidable.
In Syed Alwi Road in the Rochor catchment, shop owners said business has dropped by up to 50 per cent since work on drains started last September.
In Syed Alwi Road in the Rochor catchment, shop owners said business has dropped by up to 50 per cent since work on drains started last September.
Mr Gobikkrushnan, manager of fruit and vegetables firm Lavan Agro-Veg Trading, was one of the worst affected. 'The roadworks take up most of the road, leaving our customers with very little room for parking,' said the 50-year-old, who goes by one name.
Bank executive Joy Lee, 30, lives in Bukit Timah near ongoing construction on the Downtown Line and drainage works. She said both projects had led to 'a lot of congestion in the area'.
But shopkeepers and residents who spoke to The Straits Times saw the improvement works as necessary in the long term.
Mr Perumal Viki, a cashier at the Taj Restaurant on Syed Alwi Road, said they were needed to prevent a repeat of the floods in the past few years.
'When the floods occurred, cockroaches tried to enter the restaurant to escape the flood waters,' said the 39-year-old.
Student Vanessa Chua, 15, lives in the Tessarina condominium in Bukit Timah, which was badly affected by the 2010 floods. She said the drainage works could help prevent the area suffering the same problem again.
Engineers said disruptions could be managed with technology such as temporary decks, which are laid over underground construction work to allow traffic to continue flowing.
But they noted that several concerns would need to be addressed. Associate Professor Tan Soon Keat, a fellow at the Institution of Engineers, said the capacity of the canals could be reduced during the construction works, leading to a higher risk of floods.
Assistant Professor Vivien Chua from the National University of Singapore's civil and environmental engineering department said computer models should be used to evaluate the impact of the works on downstream areas.
'Such works could result in changes to water quality, change the way sediment is transported and affect marine ecosystems in the reservoir,' she added.
Staying above water
The Straits Times, 2 Feb 2012
Staying above water
The Straits Times, 2 Feb 2012
RESPONDING to public concerns over flash floods, national water agency PUB has announced it will spend about $750 million over the next five years on 20 drainage improvement projects. The capacity of six major canals will be increased by a significant 30 per cent to 45 per cent, and solutions specific to catchments will be implemented to meet higher drainage and flood protection standards. The PUB will also address problems at source - where rainwater falls - to better manage the run-off of storm water, and will adopt problems at receptors, where rainwater flows. These are the beginnings of a comprehensive plan of action whose implementation, progress and effectiveness will be closely watched and critiqued by businesses and the public alike, who end up soaked and stuck ankle-deep when there is a major deluge.
The national water agency should be complimented for its ready acceptance of the findings and recommendations of an expert panel on drainage design and flood protection measures. That panel itself went boldly beyond existing approaches of tackling flooding to recommend new planning parameters to reduce Singapore's vulnerability to what has become a recurrent problem amid greater development and urbanisation. The measures announced by the PUB cover the shorter term: the next five years or so. What is necessary now is to look at the longer term. A fundamental way of doing this has been suggested by the panel. It notes that catchments here are planned to handle, at most, storms that are predicted to occur once every 100 years. But places such as Britain and Hong Kong have more stringent requirements. Trunk systems in Hong Kong's urban areas have to handle storms that might take place once every 200 years. The message is that foreign best practices hold lessons and can be incorporated into the anti-flooding strategy here. Singapore can also broaden its flood-risk calculations when planning - taking into account the impact of floods on such areas as businesses and the economy, quality of life and Singapore's image as a place where things work.
All this requires time, money that is well spent, and a mindset change. Singaporeans must acknowledge that even with the best of intentions and efforts, flooding can be minimised but not completely eliminated. The Government's recognition of public and business disquiet over floods, the work of experts, and the PUB's response to recommendations signal not only the beginnings of a mindset change, but also a new determination to respond to what nature can dish out and to keep Singapore above water.
All this requires time, money that is well spent, and a mindset change. Singaporeans must acknowledge that even with the best of intentions and efforts, flooding can be minimised but not completely eliminated. The Government's recognition of public and business disquiet over floods, the work of experts, and the PUB's response to recommendations signal not only the beginnings of a mindset change, but also a new determination to respond to what nature can dish out and to keep Singapore above water.
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