Thursday, June 17, 2010

TNP 1999 : Why Orchard Road will NEVER flood...

This is such a good illustration about decision making. It is often important to know the underlying assumptions when a policy or decision is made.

Yesterday, the rainfall was very heavy in the morning. I was carrying an umbrella and still got wet.

The drains in Orchard Road is designed based on the assumption that rainfall will not exceed 100mm per hour. According to a statement by PUB, almost a 100mm of rain fell between 9 to 11am yesterday[Link].

The last major flood occurred on Nov 2009 in Bukit Timah was supposed to be a "once in 50 years" event according to Minister Yaacob[Link].

With the changes in global climate, heavy rainfall is not so infrequent anymore. Perhaps the assumptions made when we build our drains 20-30 years ago no longer holds and the risk to life and property from flash floods in a lot higher today. So is the govt going to do something or continue saying that these floods are "once in 50 years events" when they occur every 6-12 months in today's changed climate.


Date: 22 January 1999

Source: The New Paper

Why Orchard Road will never flood…

By Fong Foong Mei

Well, almost never.

For a flood to hit anywhere in Singapore, it takes a combination of high tides and about 100mm of rainfall within an hour.

And Orchard Road is protected by its mighty rain drain - the Stamford Canal.

Thanks to it, shoppers haven't had to slosh through waist-deep waters since 1960s.

But what makes a good drain?

According to a Ministry of Environment (ENV) spokesman, it's the flow capacity of a drain and not its storage capacity.

In other words, it isn't the size of the boat that matters, but the motion of the ocean.

And Orchard Road's supersucker had plenty of that.

It can empty an Olympic-sized pool before your cup of latte has time to cool.

It's very handy around this time, with La Nina is expected to bring about more wet days in the next two months.

La Nina is the weather phenomenon responsible for the heavier rains and cooler temperatures around the region.

Already, it has increased rainfall by 25 to 30 percent this year, noted a Meteorological Service spokesman.

Singapore's worst ever flood happened in 1978 when 512 mm fell in 24 hours.

Seven people died in that flood.

To prevent such disasters from recurring, the Government has spent some $1.1 billion since 1984 on about 800 km of drains all over Singapore.

How can you do your bit to avoid doing your shopping in sampans?

Simple. Just don't chuck your rubbish in the drains. Let the rain drains do their work, and go with the flow.


Anonymous said...

i am wondering the "Once in 50 Years" excuse can use how many times.

Anonymous said...

or perhaps fast population increase due to importing of human.

more human who are not taught locally, preserve the rubbish throwing culture, somehow our supposely fantastic orchard drainage system, clogging starts to take effect.

Anonymous said...

I remember I read some years back that the Marina Barrage when ready, besides serving as a reservoir, can also be used to control floods? That is the barrage gates are opened to drain off water into the sea during heavy rain and high tide.

The barrage has been in operation for some time already. How come?

Or is it I got it wrong?

Anyone can enlighten?

Anonymous said...

it is back to the past where we had floods often. seeing orchard is like the old days. welcome the sixties..we are going back to the past, not future..

Anonymous said...

I suspect this has something to do with the intense land development around orchard. Have not been to orchard rd for a long time. Last 2 wk went there.
Saw ion orchard, 313 orchard, and many more new bldgs. Even those older bldgs are upgrading themselves by tearing down and rebuilding again.
These has impact on the ground foundation.
Few yrs ago, govt introduced a dunno how many million $$$ plan to upgrade orchard rd. Now orchard more and more squeezy. Tiny plot of land also develop.

21st Dec 2012 said...

By the way, is the Istana flooded?
LOL >:)

Anonymous said...

I googled the writer Fong Foong Mei. Apparently after leaving ST( She is a malaysian on SPH scholarship ) she did a grad deg in US(Columbia?) and worked for WSJ. She won the Pulitzer prize with a group of reporters for an in-depth article on China in 2007. Of course she cannot be faulted for such a "prescient" analysis as she was only quoting MOE spokesman in 1999. However the article condition "100ml in 1 hour of rainfall" was not even met. Yesterday it was reported to be almost 100ml in 2 hours( from 9am - 11 am).

Last month there was an article in Today of the BCA award for Design and Engineering Safety Excellence Awards. One of the winners was for the diversion of the Stamford Canal for the construction of Somerset313.

BCA awards 3 engineers
05:55 AM May 07, 2010
by Evelyn Choo
SINGAPORE - The Building and Construction Authority has awarded three engineers the Design and Engineering Safety Excellence Awards.
They were recognised yesterday for their work in designing safe and creative buildings.
Ms Joanne Wong, from Meinhardt Infrastructure, was tasked with diverting Stamford Canal so that a new gleaming shopping mall, 313 Somerset could be built over it. At the same time, engineers had to ensure that the canal remained fully functional, all this while working in busy Orchard Road. The canal is now diverted and integrated into the shopping centre.
Looking back, Ms Wong recalled the challenge she faced.
"Firstly, the canal is a live canal. It collects water all the way from Bukit Timah and runs off to the barrage. And there are also other services inside the canal. We also have people crossing the canal from the MRT station and we are in a very confined site. It's located in Orchard Road, so we have to take care of the traffic within Orchard road as well."
While this team embraced urbanisation, another from the company had to make sure their project could co-exist with the past.
Their task was to build a 30-storey condominium at Kitchener Road on soft soil, while ensuring that nearby shophouses won't be affected.
Team member Yeo Choon Chong said: "If the basement construction is not designed properly and not taken care of, what would happen is the ground in the nearby area would settle, indirectly causing the settlement of the shophouses."
The project also made use of pre-fabricated bathroom units to save space, time and manpower.
The third winner of the award went to Mr Kenneth Liew of T Y Lin International. The task was to construct a seven-storey office block above a five-storey car park in Shenton Way, with the car park staying open during the period of construction.

Maybe they should have done more simulation on their model of the diverted Stamford Canal.

Anonymous said...

Complacency. The PAP is living in the past, leeching on past glories and operating on auto-pilot mode. Things in this country will get a lot worse before turning better.

Anonymous said...

Wow, didn't these PAP ministers claim they are of such uber high calibre with helicopter vision so thats why they need to be paid MILLIONS of dollars?

How come this useless Yacoob didn't see the Bukit Timah and Orchard road floods coming but blame it on climate changes, yet have no clue what to do to mitigate future floods?

Anonymous said...

When you have massive floods on Singapore’s main shopping street, it cannot be blamed on unusually heavy downpour. There is something not right in our drainage system. Since embarking on many infrastructure projects to transform Singapore, we have become more flood prone especially in areas which were never flood prone before. This is worrying! It cannot be that the more we develop our city, the more flood prone we become.

While being no experts compared to the PUB, one cannot help but make certain casual observations:

1. The Marina Barrage was meant to help alleviate floods. Yet it may have been the cause of floods. In theory, the barrage can be opened to lower the level of water in the canal system. However there will be several hours between opening the barrage at Marina Bay and for the water to flow out from Bukit Timah or Stamford Canals. Given our climate where we get heavy downpours in 1 – 2 hours, our canals may not be able to cope with the sudden rush of rain water and therefore overflow which resulted in the floods.
2. The flooding at Orchard/Paterson junction is unusual. Prior to construction of ION, the piece of empty land was a big sponge allowing rainwater to flow into the ground. However, heavy rain falling on the entire complex now cannot flow into the ground directly would naturally pond at the lowest point ie. the Orchard/Paterson junction.
3. Flooding at Balmoral Road which was thought to be eliminated has now re- emerged. Could it be due to the construction of the tunnels of the Downtown line where again rainwater cannot flow directly into the ground and thus flooding the area?

The recurring floods has tarnished our image of having 1st class infrastructure. There needs to some answers to these all too frequent 50-year freak events.

Anonymous said...

can we have another golden prediction, "PAP will never fail in the next 20 years!"

love to kick some, if not all, useless bums out of the parliament

Anonymous said...


Anonymous said...

I have a funny feeling the flood is caused by rubbish clogging the drainage system. One of the videos posted I viewed showed PUB workers clearing bags of trash from clogging drains.

Let's wait for the outcome of the investigation before happily pointing fingers again, although some might claim their reports will be fudged.

Oh well.

Anonymous said...

>>By the way, is the Istana flooded?

Ya...if the angmoh spy from above...they'll see a "swimming pool" BIGGER than that of N.Korea's Kim

heaven piss on Spore said...

Perhaps it is better for Orchard Rd and many parts of Spore to be permanently flooded, then it will really be the Venice of SEA.

Trishaw riders, taxi drivers can switch to gondolas or local made sampans.

Anonymous said...

i just can't wait for pub's investigation results. let me see, will it be like mas selamat's report - aka it's all small fry's fault?

or will it be like smrt-vandalism report - it's all people's fault for not alerting authorities earlier?

either way, i can't wait to see what brilliant excuse, to explain this "freak" incident...\

long live the pap!

Anonymous said...

As one of the readers here pointed out, PUB's investigation so far revealed that the drainage is clogged with rubbish. What the hell are the agencies NEA and PUB been doing all this while? Complacent to the extent that the core business of cleaning up Singapore is neglected?

Anonymous said...

Lucky Tan,
look the heaven is punishing the old fart and his pathetic family ...

Have u forget what what happen to the "unsinkable" titanic ?

"It was said that the builders and owners of Titanic claimed she was 'unsinkable'. The claim actually made was that she was 'practically unsinkable', close enough, but nevertheless an unfortunate statement and one which would haunt both builder and owner for years."

Those PAP fu@#$cks might have claimed Orchard road is practically unfloodable.... but not when you have curse of the murderous Junta Orchard in Botanic Garden !!!!!!!

The curse has befallen the evil party ...

Anonymous said...

It is a massive loss of face for the most expensive shopping belt in SE Asia. And as usual you won't see any PAP minister come out to say anything soon, lol.

Anonymous said...

Ya, massive loss of face for PAP but so what?

They can get away with it what?

Because they will still form the next gahmen with 2/3 majority.

Sinkies lan lan will still vote them, unless they vote with their feet.

Anonymous said...

Brillant...singaporeans will be blamed for the orchard road flood due to littering and clogging the drains...

Anonymous said...

You people are speaking nonsense because for all we know, it may be part of PAP's masterplan to make Orchard Road the Venice of Singapore !

Anonymous said...

Got to blame heaven this time.
SIN alredi got Newater, still sent so much water for what? How can heaven so blind?

Anonymous said...

Strange that nobody pointed any fingers at the litterbugs even though the cleaners have been cleaning up.

Boy, was I right!

Anonymous said...

Actually, I quite like the idea of turning Orchard Road into a Venice of sorts. In fact, I wish I was there during the flood.

Anonymous said...

This one takes the cake:

It is the small drains that drain water into the big one. If they are clogged, what is the use of the biggy?

Alan Wong said...

Maybe this concerned Minister was put in place by whoever as a political tool to bullshit the Malay voters that they have someone to represent them ? That's it.

That's our brand of meritocracy that PAP is so proud of.

Is there anything to do with the environment ? I certainly doubt so. Do you ?

Daft Singaporean said...

you're so right, we won't see any million $$$$$$ pap ministers coming out to speak anytime soon after their incompetency is exposed.

clogged drains? oh please, let me count the ways why these are clogged?

1. foreign trash throwing trash into drains - walk down orchard road, and you'll see more ft than sporeans.

2. foreign nea workers sleeping on their job, or perhaps disposing rubbish conveniently into drains.

3. poor design of diversion of stamford canal by award-winning engineers?

4. ultimately, yacoobs minister sleeping on his job for the third time (remember bukit timah and geylang food poisoning last year), joining his other chinese counterpart, wong cant sing.

you've got to love pap for the million $$$$$$ mistakes they make everywhere - orchard road, temasek/cpf investment, lta circle line collapse etc etc

Anonymous said...

You mean debris like dead leaves are the work of litterbugs? Hahahaha, so fine the trees and Nparks LOL. Please use your brains and not be always so quick to point fingers at Singaporeans like the PAP govt. Besides, you walk on Orchard rd you see more foreigners than Singaporeans so who are the litterbugs.

PUB's outsourcing and failure to do regular inspection and supervision is the PROBLEM!

Anonymous said...

The Minister of Environment deserves rottan at least 6 strokes.

Anonymous said...

News also report rain water seep into casino from it's roof top.

Nowadays mentality:
Developer want infrastructure to finish faster.
Contractor also want job to finish faster, get the money fast then if got any problem, fix it later.

Not enough planning and time to do proper job.
Rush, rush, rush and later have to spend money to fix problem (and pass the cost to consumer?).

Maybe someone can compile a detail list of recent broken infrastructure.
1. Power failure, lack of air condition @ 1st major conference hosted in IR
2. Resort World Sentosa's Battlestar Galactica ride closed down due to tech glitch
3. Orchard 'River'
4. The BT Timah 'Rich Man Area' Flood

Anonymous said...

anon @ 18/6/10 09:19,

There was an incident reported by xinmin or wanbao. Can't remember the details.
Resident of some estate complain that there was always a smell coming from a nearby monsoon drain

A witness manage to record a video of a cleaner sweeping garbage into the flowing waters (good job indeed!) instead of disposing them in trash bags.

That estate's GRC admitted the (lazy) cleaners were outsourced from some (maybe cheap) private company and I think they are malaysians (can't recall).

Anonymous said...

Debris includes litter and no one said the litterbugs were Singaporeans.

Use your head before you use your mouth. At least someone here is more creative and reasonable - point the finger at lazy cleaners, which could be a possibility although that does not justify littering.

Anonymous said...

Top pay for top talent.

Of course got talent but their talent cannot control lazy cleaners or too much dead leaves and debris clogging drain.

They are talented in other ways.

Anonymous said...

Top pay for top talent.

Of course got talent but their talent cannot control lazy cleaners or too much dead leaves and debris clogging drain.

They are talented in other ways.

Anonymous said...

The problem we have in this fucking governing that they do not want to accept responsibility. Giving excuses, pushing the blame and searching for a scapegoat is what they do best.

Anonymous said...

Wah so much problems: Mat's Escape, Kallang's Hacking, MRT Train's got painted, flooded Orchard Road.

Pay for the above Ministers in charge not enough lah. PM, more pay leh, not enough leh.

Anonymous said...

Do you expect a perfect world just cos you pay your ministers well? Grow up and stop whining!

Why don't you try getting elected if you think you can do better?

Anonymous said...

The explanation given is that the from pictures bigger canal that drains into the two as described smaller drains, if only one of them was full, and the other was empty, the water by right should have flowed back into the bigger one, but maybe insufficiently so it flooded and fell into the basement of Tong, Liat and Lucky, and that other upstream basement.

But how about this potential explanation, if the buildings downstream after Ngee Ann, the culvert/canal there when full, slows down the water upstream and thus causes both drains to swell and overflow, it would also overflow into the basements.

Such a possibility needs to be checked and it is hoped it has been because this type of storm may not come once only this season, but it may come twice.

Therefore pumps and other measures have to be on standby.

Anonymous said...

Orchard Road is now reserved for those baby prams pushing, trolley pushing, rude, rowdy, unruly babarians who does not care who they bumped into or even bother to apologise. I don't really mind if Orchard keeps on having flash floods. So people will stay away from there than I can shop in peace.

Anonymous said...

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