Jag Lyra Costamero

Published: November 27, 2023

Topic: #NextGen

Once, there stood a tall, forested mountain inhabited by a giant named Cargen Cargon. The mountain was abundant in trees, but the locals abused it by cutting more than they needed. Furious, Cargon pulled up the mountain and transferred it to another location. What was left of the mountain’s footprint is now the location of Central Luzon’s biggest flood sponge — the Candaba Swamp.

The legend has been passed on through generations of locals living in the municipality of Candaba in Pampanga. However, this tale of greed and negligence now seems to be playing out in reality.

As discussions ensue on the long-term solution to the worsening perennial problem of flooding, Central Luzon houses a natural answer to flood mitigation in the era of climate change – Candaba Swamp, the region’s biggest wetland.

It is a complex of freshwater ponds, swamps, and marshes with surrounding areas of seasonally flooded grassland, arable land, and palm savannah on a vast alluvial flood plain.

During the wet season, the swamp is usually flooded and serves as fishing grounds. When floods recede during the dry season, it is planted mostly with rice.


The 32,000-hectare Candaba Swamp in Pampanga, the biggest wetland in Central Luzon, acts as a sponge which holds flood water to avoid higher floods while slowly releasing the flood waters to nearby areas. (Jag Lyra D. Costamero/PIA 3)

A natural flood sponge

At 11 meters above sea level, the 32,000-hectare Candaba Swamp marks the lowest point in Central Luzon.

It serves as a natural flood retention basin of five small rivers – Maasim, San Miguel, Garlang, Bulu, and Peñaranda – and drains to the Pampanga River. Thus, it prevents higher floods in nine nearby towns of Pampanga namely San Luis, Arayat, Mexico, San Simon, Minalin, Apalit, Macabebe, Masantol, and Sto. Tomas.

Department of Environment and Natural Resources (DENR) Provincial Environment and Natural Resources Office Pampanga Officer-In-Charge Roger Encarnacion shared that the Candaba Swamp aids in mitigating the adverse effects of climate change by sequestering carbon in the soil, and accumulates it over a long period of time.

The swamp has a natural water retention capacity of about 1.5 billion cubic meters, equivalent to 600,000 Olympic-sized swimming pools, according to a 2009 study by Haribon Foundation.

Encarnacion pointed out that at present, the Candaba Swamp is still able to perform its crucial function of preventing floods in the area. However, the picturesque wetlands’ status as a flood basin faces various threats from within.


Farmers in barangay Paligui in Candaba prepare to dry their palay harvest. Apart from its role in flood mitigation, the Candaba Swamp also aids in food security. Data from Philippine Rice Research Institute shows that the municipality recorded the highest rice production in Pampanga in 2022 at 122,816 metric tons. (Jag Lyra D. Costamero/PIA 3)

Threats engulfing the swamp

Society for the Conservation of Philippine Wetlands (SCPW) Project Officer Darry Shel Estorba underscored that the ecological benefits of Candaba Swamp are at risk due to unsustainable agriculture and aquaculture practices, as well as land conversion since most of it are privately-owned.

“Since the productivity and income of the farmers in the area is declining due to higher prices of farm inputs, they have no choice but to seek other means of increasing their present income by using chemical fertilizer, pesticides, and worse, selling their lands to commercial developers,” she explained.

Apart from this, the swamp continues to be drained or converted into wet agriculture, severely limiting habitat for waterfowls such as ducks. Other areas have been converted into fishponds, creating discontinuous patches in vegetation cover.

She added that the swamp’s degradation is evident in the declining bird count.

Based on the Asian Waterbird Census conducted by DENR, Candaba recorded only 2,188 birds in 2019, a significant decrease from the 13,160 birds found in 2010.


The bird-watching site in barangay Paligui, Candaba submerges in floodwaters. Tourists and birdwatchers flock in the area during the dry season from November to April. (Jag Lyra D. Costamero/PIA 3)

Candaba Swamp is an important bird area within the East Asian-Australasian Flyway. Being a key biodiversity area, there are proposals to designate it as a Ramsar Site of International Importance.

In an interview, 57 year old farmer Abner Ramos shared how the swamp had changed through the years.

“In the past, we’re able to catch many fishes here. Now, they have declined in number. There are also fewer plants and birds. I think this is also due to the fertilizers that are being used,” he said.

In a 2017 meeting with farmers and fisherfolk, SCPW learned that rice production in Candaba’s farms is estimated at 100 to 120 cavans per hectare.

The amount of fish in the area had also decreased significantly, the fisherfolk told SCPW. It was estimated that their fish harvest is about half of what they used to get 20 years ago.


Rare birds are seen in a flooded rice field in barangay Paligui, Candaba. The Department of Environment and Natural Resources observes a drastic decrease in the number of waterfowls visiting the swamp as their feeding and roosting grounds.(Jag Lyra D. Costamero/PIA 3)

Call for conservation

With this, Estorba underscored the need to conserve the Candaba Swamp given its important role in climate change mitigation, biodiversity, and food security.

“We need to conserve and raise awareness in saving this area so that it will not be converted into industrial parks and warehouses and lose its ability to provide ecological and cultural services which contribute to human well-being,” she said.

She added that if the swamp is not maintained, what was known as the “flood sponge” will instead submerge Pampanga’s low-lying areas in floodwaters.

For his part, Encarnacion pressed that it is crucial to mainstream awareness to conserve the wetland.

“Since the wetland is mostly composed of privately-owned lands, owners are recommended to consider conservation and sustainability in their use and future development of the area. Local government units should always support initiatives for conservation and wise use of the wetland,” he stated.

These efforts will be necessary if the people of Candaba wish the story of Cargen Cargon to remain as it is – a cautionary tale.

This story is part of our #NextGen Climate Bootcamp in collaboration with the US Embassy in Manila.