“Never again will all life be cut off by the waters of a flood; never again will
there be a flood to destroy the earth.”—Genesis 9:11
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Each year, extensive flooding in the lowland regions impacts the personal and economic well-being of millions of Filipinos. For many individuals engaged in the formulation of disaster-reduction strategies and flood-mitigation management, it seems that the severity of floods in the country has escalated in recent decades.
On November 5, 1991, a 15-minute flash flood, instigated by Typhoon “Uring” (international code: Thelma), caused significant destruction in Ormoc City, situated on the western shore of Leyte Island. The city was inundated with debris and mud carried by the floodwaters.
According to a report from the Environmental Research Division of the Manila Observatory, the flooding lasted just over 3 hours, during which water levels increased by an average of 3 to 5 feet.
At the peak of the flood, the water surged by 7 feet in just 15 minutes. The coastal rivers overflowed their banks. Once the waters receded, they left a sediment layer that measured 2 feet in depth.
The estimated number of casualties stands at 8,000 individuals.
On December 15, 2011, just ten days prior to Christmas, tropical storm “Sendong” (Washi) struck Mindanao, unleashing a month’s worth of rainfall within a matter of hours. Residents were already asleep when the storm impacted pineapple plantations, which are unable to absorb water; additionally, it coincided with high tide and heavily silted waterways.
Gwendolyn Pang, who was the secretary general of the Philippine Red Cross at the time, told a national daily that the event was “unprecedented and overwhelming.”
It’s not only in the Philippines where floods become common. In fact, flooding is increasing worldwide, including areas that are typically safe from flooding. As the 2025 State of Flood Report by Marsh McLennan puts it: “Extreme rainfall is a primary cause of flooding worldwide, affecting regions beyond the traditional high-risk areas along waterways.”
Dictionary defines flood as “an overflowing of a large amount of water beyond its normal confines, especially over what is normally dry land.” That definition is over-simplification.
The Manual of Operational Procedures on Flood Forecasting and Warning states: “From a strict hydrological sense, food is defined as a rise, usually brief, in the water level in a stream to a peak from which the water level recedes at a slower rate. The episodic behavior of a river that may be considered flood is then termed ‘flood event,’ which is described as a flow of water in a stream constituting a distinct progressive rise, culminating in a crest, together with the recession that follows the crest.”
“Floods are due to the complex combination of weather, climatic and human activities,” explained Rosalie Pagulayan, weather specialist II of Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) during a seminar workshop convened by the Department of Science and Technology in Davao City some years back. “Most floods occur as a result of moderate-to-large-scale rainfall events.”
Floods rank among the most devastating disasters that humanity must confront. Even minor flooding can lead to various inconveniences. A significant flood can result in damages amounting to billions of pesos, affecting agriculture, infrastructure, and causing a decline in productivity within both industry and commerce, in addition to the tragic loss of human lives.
Overcrowded urban areas such as Metro Manila and Davao City may come to a standstill for several days.
“With too much rain and floods, agriculture production especially in flood-prone areas will be adversely affected with physical and economic losses,” pointed out Dr. Rafael D. Guerrero, an academician with the National Academy of Science and Technology (NAST). “Floods will wash away crops, hasten soil erosion and increase crop spoilage due to poor storage and distribution problems.”
Flooding in the Philippines is caused by a combination of natural and human-induced factors, according to Dr. Teofredo “Doc Ted” T. Esguerra, who’s trained on Urban and Wilderness Rescue, Aviation Medicine, Expedition Medicine for Tropical and Alpine Mountain Operations, Tactical Medicine, and Disaster Management.
Among the natural causes, typhoons and monsoons stand out. “The Philippines is situated in a typhoon-prone area and experiences frequent heavy rainfall during the monsoon season, leading to overflowing rivers and widespread flooding,” he explained.
“There is no month in the Philippines which is free from typhoons,” says the Philippine Atmospheric, Geophysical and Astronomical Service Administration (PAGASA), which issues weather advisories for tropical cyclones, as typhoons are also known.
“Each year, about 20 tropical cyclones enter our country,” says the country’s weather bureau. Fortunately, only 6 to 9 of these tropical cyclones make landfall.
Monsoons are seasonal wind patterns that introduce alternating wet and dry phases in tropical and subtropical areas. In the wet phase, warm, moist air from the oceans is transported inland, where it rises, cools, and condenses, resulting in substantial rainfall across extensive regions. In the country, two monsoons are responsible for flooding.
The Northeast Monsoon, locally referred to as Amihan, is marked by moderate rainfall and has the potential to cause flooding, landslides, and other water-related disasters, particularly in low-lying regions. Significant flooding has been reported in various areas, especially in Mindanao and Luzon, due to the heavy rains associated with Amihan.
The Southwest Monsoon, known as Habagat, is a seasonal wind system that originates from the southwest, transporting warm and humid air from the Indian Ocean and the South China Sea towards the Philippines. During the Habagat, the western parts of the country, including Luzon and the western Visayas, experience the most intense rainfall, which can lead to flooding.
Geography and storm surges are two other natural causes. “The archipelago’s location makes it highly susceptible to tropical cyclones and their associated heavy rainfall,” Doc Ted said, adding that coastal areas are vulnerable to storm surges, where sea levels rise due to strong winds and low atmospheric pressure during typhoons, inundating coastal communities.
Natural waterways – rivers and lakes – can become overwhelmed by excessive rainfall, causing them to overflow and flood surrounding areas.
Among the human-induced factors, deforestation and urbanization are the most common. “Loss of forest cover reduces the land’s ability to absorb rainwater, leading to increased surface runoff and flooding,” Doc Ted said. “Rapid urbanization, particularly in low-lying areas, results in increased impervious surfaces (roads, buildings) that prevent water from seeping into the ground, leading to higher floodwaters.”
Inadequate drainage systems can also be blamed. “Many urban areas in the country have insufficient or poorly maintained drainage systems, which can’t handle heavy rainfall, resulting in floods,” he pointed out.
Land subsidence is also a culprit. In some areas of Metro Manila, for instance, “groundwater extraction has led to land subsidence, making these areas more susceptible to flooding.”
The contribution of informal settlements confound the problem. “Many informal settlements are located along waterways, increasing the risk of flooding and also contributing to clogged drainage systems due to improper waste disposal,” Doc Ted said.
The disappearance of wetlands can also be attributed to these floodings. In the past, floods were not a problem in Davao City. The reason: there were still a lot of wetlands scattered all over the metropolis. But as the economy booms and buildings are constructed one after another, these wetlands are fast disappearing.
“The flooding problem of Davao City has been prevalent as early as the late 1970s,” wrote Vic N. Sumalinog, a columnist of Mindanao Times. “But over the last fifteen years, floods have exacted heavy grave damage to the population and even on government infrastructures.”
One possible solution to the problem is the maintenance of these wetlands. “Many studies revealed that wetlands in urban areas are efficient nature-based solutions (NBS)” against flooding problems, says the Interfacing Development Interventions for Sustainability (IDIS), Inc., an environmental conservation and ecological organization.
Based on a study, Davao City “settled early at a substantial floodplain estuarine with a vast network of swamps, marshes, and waterways.” Most of these areas are located in the city’s Central Business District, particularly in Poblacion, Agdao and Talomo.
Meanwhile, is there an end to these miseries brought about by typhoons and floods in the country? “Every typhoon season, the story repeats—rising waters, destroyed homes, grieving families,” observes Dr. Anthony Leachon, a Filipino physician, former government official, health reform advocate, and social media influencer.
According to Dr. Leachon, behind the floodwaters lie deeper currents: corruption, neglect, and a leadership void that’s been allowed to persist for far too long. “Billions are poured into flood control programs. But where are the results? Where is the audit? Where is the accountability?” he wondered.
“Filipinos do not lack resilience,” he further stated. “What we lack is a government that respects our strength enough to match it with integrity. The floods aren’t just a failure of infrastructure—they’re a failure of vision, patriotism, and moral leadership. This is not normal. It is not inevitable.”
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