Flood facilitation, not flood control

This is the third week of daily clouds and rain in Metro Manila and many provinces in the country. Economic and infrastructure damage must have been high as many businesses were forced to shut down on days with heavy rains and flooding, and a “classless society” of frequent class cancellations have been issued.

Philippine monsoon

The Philippines and other tropical East Asian countries have two monsoon seasons every year. The southwest monsoon or “habagat” wet season runs from June to October, and the northeast monsoon or “amihan” is a dry but cold season that runs from November to early March. Cold winds from Siberia and China blow to Luzon and other parts of the archipelago.

Habagat 2025 was terrible. I counted 12 days straight in July last year of almost no sun in Metro Manila, only clouds and rain. There were also typhoons before, during and after those 12 days. The flood-control scandal exploded that month.

Habagat 2026 started weak last June to early July. The sustained daily rains started last July 31 until this week except last Saturday (light showers) and a sunny Sunday. Then, the strong rains fell that night and worsened last Monday, August 17, flooding so many places in Metro Manila and many provinces in Luzon.

So far, we have had 20 days of daily rain. I checked the 10-day rain/precipitation forecasts for Metro Manila from Google’s Gemini and AccuWeather. Both see rain with some thunderstorms until at least August 28. This means we have four weeks of clouds and rain, and this would make habagat 2026 probably the longest sustained period of daily rain in the last 10 or 20 years, despite the current big El Niño.

Global cyclones

I checked the Climate Atlas’ Accumulated Cyclone Energy (ACE) data, https://climatlas.com/tropical/. From AI, ACE is a US National Oceanic and Atmospheric Administration (NOAA) index “measuring the total kinetic energy and lifetime activity of tropical storms, calculated every six hours by squaring a storm’s maximum sustained wind speed (in knots) while at or above 34 knots, summing those values, and dividing by 10,000.”

From January to August 2026, here are the data on (a) current ACE, (b) normal ACE for the 30-year climatological normal for the same months and (c) percent of normal, respectively.

Northwest Pacific (including the Philippines and East Asia): 195, 98, 199 percent, well above normal.

Northeast Pacific: 62, 59, 106 percent, near normal.

South Pacific: 55, 54, 103 percent, near normal.

South Indian: 107, 111, 96 percent, near normal.

North Indian is at 0, while North Atlantic is at 16 percent.

Global average: 422, 351, 120 percent, well above normal. Cyclone energy and storm strength this year so far are high.

I also checked the global ACE from 1972 to June 2026, a chart made by Dr. Ryan Maue from the same website.

ACE readings above 1,600 were recorded in 1973, 1991-1999, 2003-2007, 2015-2017 and 2019-2020, or 20 of 55 years. ACE readings below 1,600 were recorded in 1972, the years in between those periods and 2021-2026, but the second half of 2026 might pull up the overall ACE to above 1,600.

The above numbers show natural climate cycles: the warming-cooling cycle, the strong-weak ACE cycle and the stormy-less stormy years. These are consistent with the El Niño-La Niña cycle that happens every three years on average, or the annual wet-dry season cycle in the tropics, the winter-spring-summer-fall cycle in the Northern and Southern hemispheres, the water evaporation-condensation cycle, carbon emission-absorption cycle, nitrogen fixation-assimilation cycle and so on. These are natural or nature-made cycles with many precedents, not man-made “unprecedented” global warming.

Lessons on regular and annual flooding

One, our “problem” in the Philippines and the tropics yearly is lots of rain and water, not a lack of water. What we lack are lakes, both natural and man-made, dams, weirs and other water storage structures to minimize flash flooding.

Two, flooding just follows gravity. Water just wants to go down to the sea as quickly as possible. If its pathway is narrow, shallow and restricted, street flooding will happen.

Three, we need flood facilitation, not flood control structures that in some cases cause more flooding. For example, a five-meter-wide creek became four meters wide because half-meter-thick cement embankments were built on both sides. Even if there was zero corruption in building the embankment, making the creek narrow will contribute more to street flooding.

Public policy implications

Energy: have more hydroelectric plants, fewer solar plants. Have more coal and gas plants too, plus nuclear, that can produce electricity 24/7 even if the Sun is not shining, even if the wind is not blowing.

Discontinue additional solar Green Energy Auction (GEA) projects beyond what has been granted. Many upland and midland forests and fruit orchards have already been cleared and converted to solar farms, which contribute to more flash flooding.

Infrastructure: Have more flood facilitation projects. Make the creeks and rivers wider and deeper to allow the flood waters to drain to the sea as quickly as possible and protect roads and houses from flooding.

Environment: have more man-made lakes, more dams, weirs and other water storage structures, or make existing lakes and ponds wider and deeper.

Mining: amend the mining law to leave mined-out areas as open artificial lakes. Do not cover them with soil then reforest.

Public finance: cut or stop funding for climate agencies, junkets and bureaucracies. Divert public funds to more regular, annual, large-scale dredging of creeks, rivers and lakes.

In the Budget of Expenditures and Sources of Financing (BESF) 2027, Climate Change Expenditures (Table B.21), actual spending (Adaptation plus Mitigation) in 2025 was P1,045 billion, the General Appropriations Act (GAA) 2026 is P614 billion and the proposed 2027 budget is P669 billion. About 85 percent of these expenditures are for the DPWH alone, likely for the various flood control projects. DPWH and LGUs should realign their projects toward flood facilitation, allowing water to flow to the sea as quickly as possible.