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Flood Flood

It happened on a Saturday morning. Heavy rains continued to pour as a number of cars were already floating in water. A few hours later, people were soaked in neck-deep floods, while some were stranded on roads, bridges and roofs. Rich and poor alike, survivors cried for help as they witnessed their prized belongings swept away by raging floods. Such was the scene that unfolded at the height of “Ondoy,” the worst storm to hit Metro Manila in almost four decades.


On September 24, 2009, a low-pressure area inside the Philippine boundary developed into a tropical depression and was named “Ondoy,” with the international name Ketsana. Two days later, it intensified into a tropical storm, which made landfall in the boundary of Aurora and Quezon, and crossed Central Luzon for 12 hours. On the same day, it enhanced the habagat, which brought rains concentrated in Metro Manila, Central and Southern Luzon, and some parts of Visayas and Mindanao.
source: PAGASA
At 455 millimeters, the amount of rain accumulated in Metro Manila within 24 hours surpassed the normal monthly amount in the metropolis, according to PAGASA.


“Ondoy” exited the Philippine boundary on September 27, 2009 leaving a wake of devastation
source: NDRRMC

Based on the final report of the National Disaster Risk Reduction and Management Council (then the National Disaster Coordinating Council), Tropical Storm Ondoy affected 4.9 million people in the country. The enhancement of the habagat resulted to floods in 1,786 barangays in 26 provinces, and landslides in some parts of Cagayan, Pampanga and Camarines Sur. The catastrophic storm also took 464 lives, injured 529 and caused 37 unaccounted for. Damage to infrastructure and agriculture amounted to P11 billion.


On the seventh anniversary of the disastrous storm, we visited Marikina, one of Metro Manila’s hardest-hit areas. We asked survivors to share with us some of the lessons that the Ondoy tragedy has taught them. Here are some of their answers:
1) Preparedness is a must.

“Sobrang takot. Kapag may nagbabaha na ngayon, nagre-ready na kami. Nag-aabang na kami, baka sakaling bumaha, ay lumikas na tayo sa matataas na lugar. Alam na namin ang gagawin namin kapag andiyan na eh. Hinahanda namin ‘yung mga gamit namin. May plano na. ‘Yung kahandaan na kasi noong una, biglaan yun. Natakot din kami. Hindi namin alam ang gagawin namin.”
(It was frightening. Now, when flood occurs, we start to prepare. We monitor updates, while planning our evacuation to higher grounds. We were afraid before but now, we already know what to do.)
– REY BAYAOA, a 52-year-old shoemaker in Tumana who saved his family of six during Ondoy
“Kasi dati ang ugali namin, pateka-teka kami. Once na nagkakaroon ng bagyo, kampante ‘yung mga tao na hindi tataas ‘yung tubig o kaya, kakayanin ng bahay nila. Pero ngayon, kapag sinabing may bagyo at nag-signal number three na sa Metro Manila, automatic, ‘yung mga gamit na kayang iakyat, tinataas na,”
(We were complacent before. We were confident that our homes could protect us from flood. But now, we automatically move our things to higher ground, especially when signal number 3 is raised in Metro Manila.)
– KATRIN ABELLA, 24-year-old employee who recalled losing four neighbors due to leptospirosis that became rampant after Ondoy.
2) Be familiar with warning systems.

“Mahalaga, para makapaghanda ang mga tao. Meron na rin dati, nag-a-alarm. Kapag 15, alert ‘yun. May maiksi, may mahabang tunog. Kapag mas mahaba, malapit na sa critical ‘yun, mga 17 na yun. Tsaka kapag matagal ang ulan, nakabantay na kami. Ang alam ko, kapag hindi malakas ang hangin, habagat yun. Kapag may ulan at hampas ng hangin, bagyo. Okay naman ang PAGASA, maganda ngayon. High-tech na.”
(It is important that we know various alarms from the river warning system; a shorter siren means alert level or a river height of 15 meters. A longer siren means an almost critical level, close to 17 meters. When the rains are prolonged, we are already on the lookout. As far as I know, habagat has weaker winds while a tropical cyclone has stronger ones. PAGASA is instrumental since they have more advanced technology now.)
– ROMEO BUENAVENTURA, 58-year-old resident of Barangay Barangka who recalled how they witnessed the sudden rise of Marikina River in September 2009
3) Never be complacent.

“’Yung bahay namin, wala pang one kilometer away from the Marikina River… Sina mama, naging kampante sila na hindi kami aabutin ng baha. ‘Yung bahay kasi namin hanggang third floor, maliban dun, first experience naming ‘yun na sobrang baha. Sa mga dati naming bahay, kapag sinabing baha, hanggang tuhod, hanggang bewang, hindi naming in-expect na kapag sa Marikina pala, floor by floor ng bahay ang pinag-uusapan. So hindi sila lumikas… may dumating na chopper mula sa LGU tapos iniligtas sila.”

(My mom lives one kilometer away from the Marikina River. My mother was confident since our house had three floors. Before, floods only reached up to our knees and waists. We were not used to the kind of massive flood Ondoy brought so they did not evacuate. Fortunately, a chopper came to rescue them.) – KATRIN ABELLLA
4) We must care for the environment.
“Yung mga ilog, ginagawa ng ibang tapunan. Kalinisan dapat. Dapat tinatapon sa lagayan ng mga basura. Hindi sa mga ilog.”

(Some people throw garbage into the rivers. We must observe cleanliness. We should manage wastes properly.)

– GENARD GUEVARRA, 21 years old and lives just a few meters away from the Marikina River
“Kailangan talaga may pagmamahal sa kalikasan. ‘Wag babuyin. ‘Wag lagyan ng basura. Dito ang takbuhan ng ulan eh, mula sa Quezon City at Montalban. ‘Yung mga basura, inaagos.”
(We should love our environment. We shouldn’t degrade it. Rubbish from Quezon City and Montalban are brought here to our city through the river.) – ROMEO BUENAVENTURA

5) Cooperation matters.

“Gan’un na lang kaimportante ang kooperasyon ng mga LGUs sa mga kalamidad na kagaya ng Ondoy kasi nga sila ‘yung may kontrol. Kumbaga, sila ‘yung medium ng mga tao para malaman kung gaano na ba kataas ‘yung tubig sa ilog o kung kailangan na ba talaga lumikas. Nakadepende rin sa kanila ‘yung safety ng mga tao, halimbawa, mali sila ng information na ibinigay… mas maraming mamamatay.”
(Cooperation among local government units is important during calamities since they have control. They also inform us how high the river is, or if we already need to evacuate. Our safety depends on them. If they give us wrong information, lives will suffer.) – KATRIN ABELLA
6) There is hope after a tragedy.
“Yung mga gamit, kahit paano, unti-unti namin na-recover. Syempre, hindi naman mabibigla na bibili ulit. Ang mahalaga, unti-unting bumabangaon.”
(We cannot easily replace our lost possessions, but we are trying to recover, little by little. What matters is that we will stand up again.) – REY BAYAOA
7) Keep the faith.
“Anim kami. Wala namang napahamak sa amin. Awa ng Diyos, nailigitas ko lahat ng pamilya ko. Kumpleto pa rin kaya ngayon. Kapag umuulan, nakahanda na kami bilang mag-anak.”
(There are six of us in the family. No one was hurt. By the grace of God, I was able to save my family members. Now, when it rains, our family automatically prepares.) – REY BAYAOA
More than half a decade has passed, and still, memories from the Ondoy calamity burn clear in people’s minds. But more important than the tragedy are the valuable lessons we’ve learned to make sure that we don’t suffer such great devastation and loss ever again.


As the saying goes: When it rains, it pours. But in most parts of Metro Manila, the more accurate adage seems to be: When it pours, it floods. This is especially true in late June and early July until October when temperatures drop and rains fall due to the southwest monsoon, commonly known as habagat. Typhoons strike our country with an average number of 20 each year.

In this regard, the Metro Manila Development Association (MMDA) has identified more than a hundred flood-prone areas in Metro Manila. We asked the help of Mr. June Trinidad, Communications Operator of MMDA Flood Control to narrow down the list to the top three.

1. R. Papa Street in Sampaloc, Manila

Why it easily floods: The high tide along Manila Bay, heavy downpour, and the heavy foot traffic in the area (where an LRT station is located), which usually means more trash in the streets, are just some of the factors why this area is frequently flooded.


Faith Moneda, an 18-year-old student from the Technological University of the Philippines, who passes by this route on her way to school, has learned to adapt to the flooding situation. “When I find out that rain is coming, I pack my slippers along with my umbrella and rubbing alcohol.” She surmises, “I think the problem is the blocked drainage system because of the trash. Because of this, I strongly urge my fellow students to limit the use of plastic and to properly dispose of wastes.”

2. Araneta Avenue, Del Monte Avenue, and Quezon Avenue in Quezon City

Why they easily flood: These areas are filled with structures and don’t have enough trees to absorb floodwater. A total of 104,000 families in these areas were identified by the Department of the Interior and Local Government as living in danger zones, such as railroad tracks, garbage dumps, canals, rivers and creeks.


Antony Alcorin, who plies these routes while selling fruits talks about his experience on floods: “I felt scared when I experienced my first flood. The water was above my cart, and I could not cross the street because of the stranded cars. But I still had to sell my fruits or else they would be wasted. Floods keep me from earning money. In my opinion, these floods are caused by clogged canals. I suggest that these should always be cleaned and deepened.”

3. Pasong Tamo and Buendia Avenue in Makati City

Why they easily flood: There are a lot of road construction and improvements in these areas—some of it are along the Magallanes Tunnel Drainage System, Chino Roces Avenue and within the vicinity of District I in Makati City. Other flooding factors include the overflowing of the Pasig and Marikina Rivers.


Danilo M. Sobebe, a taxi driver for 20 years says, “I have many flood encounters especially in Makati. If I find out that my route is flooded, I change direction. If that’s not possible, I wait for the floods to subside or I just struggle with the traffic. I think floods are caused by road reconstructions and clogged drainages. I don’t want to see people throwing their trash everywhere. They don’t know that this affects everyone.”

According to Mr. Michael Puya, a Communication Equipment Operation under MMDA Flood Control, these places are classified according to flood frequency and flood level—the latter measured through stop gauges that use inches as a unit of measurement. According to their records, these places experience floods with an average height of waist-deep or 36 inches. Floods here usually reach a minimum of six inches.

Metro Manila is a low-lying area; therefore floods come from the surrounding elevated regions, all the way up to the Sierra Madre Mountains. Ground water extraction due to deep wells is causing major areas of the metropolis to sink. Global warming and climate change in the past decade have unleashed nonstop rains and stronger typhoons, which in turn, have created floods, destroying thousands of homes and roads, and submerging 90% of Manila.

Rapid urbanization is also a culprit and should be addressed properly. Houses, buildings, roads, parking lots and infrastructure cover ground that can absorb much of the storm water that falls on the metropolis. Meanwhile, road improvements add to soil wastes that clog the drainage. We need to recover our forest cover to reduce the amount of rain that floods our low-level metropolis.

Where do these floods go?
A process called the Lateral Scheme of Continuity was explained by Mr. Bobot Balboco of the MMDA Flood Control shares these stages:

1. Flood water enters an inlet or opening.
2. It goes through gutters, concrete tubes of 24 inches called Reinforcement Concrete Circular Pipes that are placed all over Metro Manila.
3. Water goes down the Drainage Lateral.
4. Water flows and converges at the Main Drainage.
5. The collected water flows to the esteros or creeks.
6. Water enters the Pumping Station or Flood Gates, whose main function is to pump out water from esteros into the water sources such as the Pasig River and Manila Bay.

But the citizens we’ve interviewed seem to have hit the problem right on the head. In these pumping stations, a total of 8,000 tons of garbage a day are being collected, equivalent to 13% of the country’s total garbage.

Balboco demonstrates the problem by using a sink and two pails of water. “This huge amount of water poured into the sink will surely fill the whole thing, but we can observe that it will smoothly subside afterwards. But imagine the sink is filled with trash that has clogged the waterways.” This way, floods will surely occur because of the blockage. But as Balboco fittingly concludes,“The response is within our hands.”

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According to a press conference held by PAGASA last August 24, 2016, La Niña is expected to develop with a probability of 55 to 60%. According to Analiza Solis of PAGASA’s Climate Monitoring and Prediction, the phenomenon, which will be likely weak and short-lived, may occur in either in late September or October this year.

Understanding La Niña

La Niña, which literally means “the girl” in Spanish is characterized by unusually cooler than normal sea surface temperatures in the Central and Eastern Equatorial Pacific.

If and when La Niña comes, more rainfall is expected over the eastern side of the country, considering that the projected cyclone tracks move close to the Philippine Area of Responsibility (PAR) during this period. About 5 to 9 cyclones are expected to enter the PAR from September to February 2017. `

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Impacts of La Niña

Back in 2005 to 2006, areas in Calapan in Oriental Mindoro, Camarines Sur, Quezon, Iloilo and Palawan experienced severe floods, while landslides were triggered in Isabela. Such incidents occurred while the northeast monsoon prevailed with Tropical Depression “Agaton” hitting Visayas and Mindanao.
This also coincided with a weak La Niña.

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The weather bureau has already given precautions to the public to stay alert and to keep monitoring the development of La Niña. Also, all concerned agencies are advised to take precautionary measures to mitigate the potential impacts of the looming La Niña.

Global Watch on La Niña

There are also impacts of La Niña worldwide.

La Niña typically contributes to more hurricanes in the Atlantic. Last month, Hurricane Gaston hit the mid-Atlantic, while in Norway, more than 300 wild reindeer were killed by a lightning strike at the national park.

In Asia, Indonesia is experiencing La Niña until September. Last July, over 50,000 people were affected due to floods when a river overflowed in East Java. There were also four people reported dead in North Sulawesi due to landslides. The only good thing about La Niña is that it will keep forest fires from spreading.

Meanwhile, in South Africa where there is no assurance of a La Niña, residents are hoping for rain. According to Australia’s Bureau of Meteorology and the UN weather agency, if ever La Niña does occur in South Africa, it will be a weak one. This year, the country recorded its lowest rainfall since 1904. If another dry spell hits the country this summer, its agricultural production would greatly suffer. South Africa only managed to produce 7.2 million tons of maize, down 28% from last year’s 9 million tons.



New studies from the International Atomic Energy Agency (IAEA) researchers showed that climate change does not only affect the severity or amount of rain but also the precipitation patterns.

According to Al Gore, the founder of the Climate Reality Project, since warmer air holds more moisture, rising global temperatures also contribute to the changes in rain patterns, including rain’s occurrence, duration and distribution. Gore also stated that global water vapor increases by 7% for every degree centigrade of warming.

Climate change can affect two types of rain – stratiform and convective. Convective rain, which occurs more frequently, is sudden, intense and local. Meanwhile, the stratiform type is lighter and can fall over a larger area for a longer time.

Isotopes as clues

In June 2016, hydrology specialist Pradeep Aggarwal and his co-authors announced that the oxygen and hydrogen isotopes in rain samples provided data on the ratio of these two rain types.

Isotopes are atoms of the same element that have different numbers of neutrons that result to different atomic weights. The condensation and evaporation of water affect the ratio of heavy to light isotopes.

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Observing and understanding how the water cycle responds to climate change is difficult and critical. These findings could also contribute to a better understanding of how climate change affects rainfall patterns, which could later help in adaptation and precipitation models in the future.

Rainfall and Climate Change

As temperatures rise, air becomes warmer. Hence, more moisture evaporates from land and water into the atmosphere. More moisture in the air means more precipitation and heavy downpour.

The problem is that extra rain is not evenly distributed throughout the globe. Because of the shifting air and ocean currents brought by climate change, some countries may receive more or less precipitation than others. According to the US Environmental Protection Agency (EPA), the world is already getting more rain and snow than it did a century ago.


Looming La Niña

PAGASA and other international meteorological agencies confirmed a 55 to 60% probability of La Niña development in the last quarter of 2016. La Niña is the unusual cooling of ocean temperatures in the Central and Eastern Equatorial Pacific.

Because of this weather phenomenon, more active rainfall activity is expected in Southeast Asia, including the Philippines. PAGASA said that after the sweltering dry months, we are now anticipating slightly cooler and wetter months ahead.

Rising temperatures triggered by climate change and the previous El Niño episode may begin to decelerate due to La Niña. According to the University of New South Wale’s Climate Change Research Center, a rise in global temperatures may still occur, but it won’t be as rapid as what had been observed last year.

US Climate Prediction Center
International Atomic Energy Agency
University of New South Wale’s Climate Change Research Center
US Environmental Protection Agency