Why we've been getting so much rain

Grace Chua Straits Times 26 Jun 10;

THE heavy rain which battered most of Singapore yesterday was due to a Sumatra squall, a seasonal line of thunderstorms, which causes rain before dawn and in the morning, the National Environment Agency said.

About 100mm of rain fell between 8am and 9.30am yesterday, causing flash floods from Balestier to Bukit Timah.

Similar to last week's deluge in Orchard Road, Friday's downpour was more than 60 per cent of June's average monthly rainfall of about 162mm.

This makes June a real dampener; with total rainfall recorded this month floating currently at 204.3mm.

Sumatra squalls take place during the south-west monsoon from June to September, but June is typically fairly dry.

However, Nanyang Technological University climate expert Koh Tieh Yong noted that two other weather phenomena coincided with the south-west monsoon to make the recent weeks more water-logged than usual.

One is the intra-seasonal oscillation, where a 'supercluster' of clouds lingers over the equator, from the Indian Ocean all the way to Peru in South America.

This results in a wet period and a dry period, which together last between 30 and 60 days, though experts do not know precisely what causes this cycle, said Assistant Professor Koh.

The other is a transition to La Nina, the 'sister' to the El Nino weather phenomenon. During La Nina, warm ocean-surface temperatures over the Western Pacific heat the surrounding air, which rises and condenses, bringing rainfall to the region. The last La Nina period, from 2007 to 2008, pounded Singapore with heavy thunderstorms.

Prof Koh said that this was not the first time the three climate phenomena have converged, and it will happen again.

But, he added, natural weather variability means the heaviest rain can fall anywhere from Malaysia to Indonesia, and could even miss Singapore the next time.

Elsewhere in South-east Asia yesterday, stormy weather was the norm.

The World Meteorological Organisation, a United Nations agency, reported heavy rain in the Indonesian territories of Kalimantan and Java as well as in southern Thailand, while the Malaysian Meteorological Department issued a warning for thunderstorms and heavy rain with strong winds over Johor, Malacca and Negeri Sembilan early yesterday.

Here, the PUB said, short showers with thunder can be expected mostly in the late morning and afternoon for the rest of the month.

Widespread showers with thunder and occasional gusty winds in the morning can be expected on one or two days.

More about the Sumatras on wild shores of singapore.

Rain causes havoc - floods, fallen trees, jams
Grace Chua & Hoe Pei Shan Straits Times 26 Jun 10;

A SHORT, sharp rainstorm yesterday morning created havoc islandwide, causing at least 25 trees to fall, snarling traffic on major roadways and overwhelming drainage systems.

Four people were hurt by the falling trees - all were sent to hospital for treatment of lacerations and other injuries - and in at least one instance, rising waters led to the Singapore Civil Defence Force (SCDF) being called out to perform rescue duties.

In that incident, 18 children were trapped in a childcare centre at Telok Kurau Lorong G when water rose to knee level.

SCDF officers evacuated the children to a neighbouring house and later pumped water out of the centre.

The storm yesterday was more intense than the one last Wednesday, which dumped 100mm of rain in a three-hour downpour and flooded Orchard Road and other areas.

Yesterday, the same amount of rain came down between 8am and 9.30am.

While last week's floods at Orchard Road resulted because of a partially blocked drain, yesterday's rainfall simply overwhelmed the drainage system in many areas.

As a result, flash floods occurred in Geylang, MacPherson Road, Old Airport Road, Thomson Road and Bukit Timah, among others.

Unlike last week, however, no widespread damage was reported and floodwaters subsided within an hour.

Nevertheless, the rising waters caused much disruption: Dustbins were upturned and basement carparks were threatened, sparking calls to car owners to evacuate.

Motorists were among those most affected, as falling trees and branches in several areas left people headed to work stuck in idling vehicles, sometimes for hours.

The worst incident occurred along the Central Expressway (CTE) towards the Seletar Expressway (SLE), between the Ang Mo Kio Avenue 1 and Avenue 3 exits. A 15m-high tree fell onto several vehicles around 9am, blocking four lanes and causing gridlock.

Two people were hurt in the incident: a woman suffered bruises and a man injured his left hand.

Traffic in at least six other spots was also diverted because of fallen trees. The affected areas included the Buona Vista exit on the Ayer Rajah Expressway and the junction of Kampong Bahru Road and Silat Avenue.

In a statement yesterday, the National Parks Board said the bad weather, not tree rot or poor health, led to the incidents.

PUB, the national water agency, attributed the floods to heavy and intense rain that the drainage system could not handle.

It said that after each flood, a review is carried out and an investigation on the cause of the flooding is conducted before it decides on the next course of action.

When asked, it said that in some instances, upgrades are planned but have not been implemented yet, and cited Bukit Timah as an example.

However, PUB insisted that the drainage system is continually being improved - to the tune of $150 million a year.

Last week, Mr Yap Kheng Guan, the director of PUB's 3P (Public, Private, People) Network, said: 'We can't build very big drains that will be empty most of the time.

'All these flash floods, much as we try to reduce them, we will continue to see them here and there.'

But, he added: 'We'll definitely do all we can to make sure that the kind of flooding we had in Orchard Road doesn't happen.'

However, several residents called on PUB to investigate further.

Thomson Road resident Shama Bano Khan, 32, whose compound was flooded, said she suspects choked drains were the cause.

'There have been rains this heavy, but it has never flooded like this,' she said.

Rainfall this month has been higher than normal, the National Environment Agency (NEA) said yesterday.

So far, 204.3mm has been recorded, above the 162.2mm monthly average for June, but well below the highest recorded rainfall for the month, 378.7mm, in 1954.

The heavy rainfall, the NEA added, was from a Sumatra squall, a line of heavy thunderstorms with gusty winds, which typically strikes Singapore before dawn and in the morning.

Yesterday's floods were the seventh major set of flash floods in the last four years.

Besides last week's Orchard Road flood, previous incidents have ranged from November's Bukit Timah deluge, which did a million dollars' worth of damage to high-end cars, to 2007's Lucky Plaza and Liat Towers inundation.

Flash floods occur when there is severe rainfall in a very short time.

But Singapore is also susceptible to flooding when a heavy storm coincides with a high tide, or if there is non-stop rain over a long period.

For the latest weather reports and heavy rain warnings, the public can call the NEA's weather forecast hotline at 6542-7788 or visit www.nea.gov.sg or weather.nea.gov.sg

To report obstructions in drains or check on the flood situation, the public can call PUB's 24-hour call centre at 1800-284-6600.

Additional reporting by Jalelah Abu Baker and Bryan Toh

Road chaos as trees fall in storm
Straits Times 26 Jun 10;

RAIN and wind felled trees islandwide yesterday, blocking traffic for more than an hour in some areas.

All in, 25 trees toppled over, out of a population of some 1.3 million trees here.

The worst jam was on the Central Expressway (CTE), where a fallen tree blocked four lanes of traffic, took two hours to clear and resulted in two people being sent to hospital.

The National Parks Board (NParks) said in a statement that trees and branches typically fall due to bad weather, not to poor health or tree rot.

About a million trees are under NParks' care at parks and nature reserves and along roads.

There are no particular areas where Singapore is more prone to tree failure, NParks added; tree fall depends on the direction of the monsoon storms and strong winds.

About 1,000 fallen trees and branches are reported each year, down from some 3,000 in 2001.

Urban trees bounded by roads may have less space for root systems to anchor, and there may be unseen damage caused by road and drainage works, pointed out Mr Veera Sekaran, of landscape firm Greenology.

For instance, the 18m-tall raintree which toppled in front of the Istana earlier this month had a rotten root underground. That, combined with an unbalanced tree crown, caused it to fall.

Preventing tree fall, Mr Sekaran added, is a matter of picking species which do not have soft branches or rot easily; and having trained arborists to carry out regular inspections.

NParks has a programme to inspect trees along major roads from root to crown every 18 months, and every tree under the agency's charge is checked at least once every three years.

The parks agency also has a programme to replace storm-vulnerable trees such as the Albizia, which, with its soft wood and fast growth, is less stable in thunderstorms.

Though they require maintenance, Mr Sekaran said, Singapore's trees do benefit the environment by giving shade, cutting dust and noise, and absorbing volatile organic chemicals and carbon dioxide from the atmosphere.


Children evacuated, motorists stranded
Childcare centre flooded, motorists left stranded as flood causes mayhem
Hoe Pei Shan & Linette Lai Straits Times 26 Jun 10;

THE cost of the flood damage at childcare centre, Our Juniors Schoolhouse @ Telok Kurau, has still to be assessed after yesterday morning's deluge.

The 18 children and seven staff had to be evacuated after the centre found itself knee-deep in water just after 9am.

The Singapore Civil Defence Force (SCDF) and the staff then spent most of the morning bailing out the water.

The centre's spokesman, Ms Imeelia Ismail, told The Straits Times that they hope to be open again on Monday, but if it is still water-logged: 'We've arranged with other Cherie Hearts kindergartens in the area and we will deploy the children there if necessary,' she said.

She added that PUB will be at the centre today to assess the damage and check on the cause of the flood.

Elsewhere, rising water levels in several areas created mayhem and severely affected traffic flow across the island.

Along Sin Ming Road, residents stood by helplessly as giant green rubbish bins began floating away in the rising floodwaters.

Many were late for work, trapped by the water and deterred by the gusty winds, or stuck in massive jams along a number of expressways.

A flooded carpark in Bedok South near Block 2A also dampened the mood as motorists were unable to leave.

Said resident and IT saleswoman Madam Patricia Kwa, 30, who was delayed for more than an hour: 'It is very frustrating, especially not knowing why these floods are suddenly happening.'

The SCDF also had to assist a taxi driver and his passenger who got stuck in high floodwaters at the junction of MacPherson Road and Kampong Ampat.

The officers had to manually pry open the doors to the vehicle, and guide both passenger and driver to safety.

Sporadic flash floods were not, however, the only problem yesterday.

A motorist and his wife had a close call when a tree smashed into the rear of their car along Beach Road.

Businessman Zen Tay and his wife were completely taken aback when the tree - which Mr Tay described as 'five storeys' high'- fell on the Mercedes as it was reversing, breaking the glass in the rear and creating a large dent in the boot.

Said Mr Tay, 29: 'We were very lucky. I hope something is done before other trees cause more damage.'

Businesses count the cost of floods again

Yesterday's heavy rain causes localised flash floods in a number of areas
Uma Shankari Business Times 26 Jun 10;

A FRESH round of flash floods hit Singapore yesterday - even as businesses were still dealing with the fall-out from last week's Orchard Road flood.

National water agency PUB said 100mm of rain fell between 8am and 9.30am yesterday. That is the same amount of rainfall that fell on June 16 and caused massive floods at Orchard Road. The amount is also more than 60 per cent of the usual average rainfall for the entire month of June. Yesterday's heavy rain caused localised flash floods in a number of areas including Bukit Timah Road/Dunearn Road, the junction of Thomson Road and Balestier Road, and Old Airport Road. The flash floods subsided within 30 minutes, PUB said.

Fallen trees, combined with the floods, also caused chaos on some roads. An uprooted tree fell across the entire northbound carriageway at the Central Expressway (CTE) near Ang Mo Kio, making the expressway impassable to traffic. The incident caused a massive jam which tailed back several kilometres and traffic had to be diverted away.

Orchard Road, one of the worst-hit areas during the last downpour, was spared yesterday - although a fallen tree near Orchard Central blocked two lanes of traffic. Businesses at Lucky Plaza and Liat Towers - which were major casualties during last week's floods - were not affected by yesterday's downpour. But for retailers already hurt by last Wednesday's flood, it was still not back to business as usual yesterday.

Luxury retailers Hermès said that it has not started on repairs at its Liat Towers boutique and is still in the process of speaking to its insurers. Other retailers in the building and nearby Lucky Plaza, which was also badly hit, also had not resumed operations as of yesterday.

But insurance claims - both from retailers as well as from vehicle owners who found their prized cars submerged in muddy floodwaters - have largely come in.

NTUC Income said that to date, it has received about 30 flood-related claims from vehicle owners, and a handful of claims from shop and building owners. The company estimates payouts to be a few hundred thousand dollars each for property and motor insurance.

'We believe the majority of claims have already come in,' said Pui Phusangmook, NTUC Income's senior vice-president and general manager for general insurance. 'Our assurance to our policyholders is that we will honour all policy terms relating to the flood damage, and that we will be fair and prompt when assessing and handling their claims.'

MSIG Insurance has also said that it has seen property and motor vehicle claims. Market watchers have estimated that the total amount of damages from last week's flood could cost millions of dollars in total.

Additional reporting by Felda Chay

Flash floods wreak havoc across S'pore in morning rush hour
Imelda Saad Channel NewsAsia 25 Jun 10;

SINGAPORE : The heavy downpour on Friday morning caused chaos on the roads with another bout of flooding across the island.

At least four people were injured, and several others trapped by rising waters and fallen trees.

This comes just a week after flash floods wreaked havoc at Singapore's Orchard Road shopping belt.

A van crushed by a massive tree was just one casualty of the storm that lashed through the island early Friday morning. Gusty winds uprooted the entire tree from its roots.

The Singapore Civil Defence Force (SCDF) said two people in the van were injured and were sent to Tan Tock Seng Hospital.

Along the Central Expressway (CTE), another tree fell onto a car, causing a massive traffic jam which stretched several kilometres.

Traffic Police were on hand to divert traffic away from the CTE towards SLE in between the Ang Mo Kio Ave 1 and Ang Mo Kio Ave 3 exit due to the fallen tree.

For many motorists, visibility on the roads was down to just a few metres.

A similar scene was observed near Orchard Central. A fallen tree blocked three lanes of traffic.

Responding to queries from MediaCorp, the National Parks Board said it attended to 25 incidences of fallen trees at various locations islandwide.

Its assistant director for Streetscape (Projects), Ng Cheow Kheng, said: "Most obstructions involving fallen trees or branches this morning were cleared within the hour, or pushed to the road verges to be cleared later.

"The exception was the fallen tree at the Central Expressway (after Ang Mo Kio Ave 1), which took about two hours to remove due to traffic conditions."

Mr Ng added: "We look after about 1 million trees located within parks, nature reserves and road verges, and they are generally healthy. We also have a sound tree safety inspection and maintenance programme in place.

"Our regular checks showed that incidences of fallen trees or branches were mainly due to adverse weather conditions rather than poor health or tree rot. ... Apart from regular checks on trees and soil conditions, we also identify trees which are vulnerable during rainstorms and replace them with stronger ones."

At a childcare centre at Telok Kurau, in the eastern part of Singapore, 18 pre-school children and seven adults were evacuated as knee-deep waters gushed into the building.

The SCDF used pumps to extract water from the affected building.

MediaCorp viewers also sent in videos of vehicles trapped by rising waters.

Singapore's national water agency PUB said heavy and intense rain fell in many parts of Singapore. It added that 100 millimetres (mm) of rain fell within an hour, between 8am and 9.30am.

That is 60 per cent of the average rainfall recorded for the entire month of June. The same amount of rainfall was recorded on June 16 when storms led to the massive flooding in Orchard Road.

PUB said the heavy rain on Friday morning caused localised flash floods in a number of areas and the waters subsided within 30 minutes.

The National Environment Agency (NEA) told MediaCorp that "the total rainfall recorded for June 2010 to date at the Climate Station in Changi is 204.3mm".

This has surpassed the average monthly rainfall of 160mm for June. Two heavy downpours, including the one on Friday morning, in the last ten days contributed to most of the rainfall - about 200mm.

NEA added: "Although the Southwest Monsoon months of June to September are characterised by relatively dry weather, it is still possible for Singapore to experience such intense showers from time to time.

"For the rest of this month, short-duration showers with thunder are expected mostly in the late morning and afternoon. Widespread showers with thunder and occasional gusty winds in the morning can be expected on 1 or 2 days."

Since the flooding last week, PUB has installed gratings at canals at Holland Road and behind Tanglin Shopping Centre.

All in, PUB said it will spend S$25,000 to install five gratings in drains upstream from the Stamford Canal, which runs in the heart of Orchard Road. The gratings are designed to trap debris while allowing water to flow through.

Those affected by the floods are hoping such measures will mitigate any future problems.

At the Lucky Plaza shopping complex, a bookstore which was one of the many shops hit by the floods last week was luckier this time round.

Bernard Chung, owner of Discount Bookstore, said: "The flood in my memory was very clear because I was here at about 10.15am in the morning and the water came in so quickly it covered up the whole place and it turned into a swimming pool at the basement.

"This morning I was concerned, so I came a little bit early just to make sure, but thank god nothing happened."

Interestingly, shopkeepers are now offering post-flood discounts at Lucky Plaza, in a bid to lure back the crowds.

- CNA/al