Accountability adrift: Murky gov’t data draw dreary picture of Laguna de Bay

May 23, 2024

(Second of two parts. Click here for the first part.)

MANILA, Philippines — An investigation by has shown that large amounts of human and animal waste have pushed Laguna de Bay to a tipping point, from where the lake and all those dependent on it may not be able to recover.

The Laguna Lake Development Authority (LLDA) has faced criticism about its administration of the lake and, specifically, its willingness and ability to hold polluters accountable.

In part two of a six-month investigation of the contamination of Laguna de Bay, through a series of Freedom of Information (FOI) requests, we try to uncover who the LLDA has caught polluting Laguna de Bay and its tributaries and what is being done to hold them accountable.

The LLDA responded by denying FOI requests, while the Commission on Audit (COA) has flagged the LLDA for failure to collect rent and other fees to fund proper oversight and monitoring and deter polluters.

Instead, we uncovered scientific data identifying tributaries with the most contaminated water pouring into the lake and measured the impact of the contamination on local communities, including fishermen.

Stopping the waste at the source

In Part 1 of the investigation, we revealed the startling levels of contamination in Laguna Lake. Experts agreed that the major source of this contamination is dirty water carried in by surrounding rivers and tributaries.

“These sewage channels […] it’s like they all converge here. It’s almost like this place is the biggest septic tank because it catches all the runoff from the rivers,” said Benjie Reyes, president of the Barangay Fisheries and Aquatic Resource Management Council (BFARMC) in Barangay Bayanan, Muntinlupa City.

Laguna de Bay, until now, has kept its designation as a Class C body of water, supporting fisheries, recreational activities, and agriculture, but the water emptying into the lake is not.

“Unfortunately, most of the tributaries of Laguna Lake were declared worse than Class C,” said Emiterio Hernandez, an engineer and officer-in-charge at the general manager’s office of the LLDA.

“Some were even worse than class D — including those that are located near Metro Manila. These tributaries are only fit for irrigation,” he said in a previous interview with

LLDA’s quarterly water quality reports indicate that all tributary river systems of the lake consistently failed to meet the acceptable level of fecal coliform counts.

This was further highlighted by a study co-authored by Dr. Windell Rivera, a microbiology professor at the University of the Philippines Diliman. It showed that all tributary river systems monitored by the LLDA failed to meet water guidelines for classes A to D for coliform from 2018 to 2020.

New studies identify dirtiest tributaries

A recent study published in April 2024 in the Journal of the American Society for Microbiology highlights environmental concerns in three tributaries feeding into Laguna de Bay.

Researchers detected heavy metals, antibiotic-resistant bacteria, and fecal indicators in the San Cristobal River near Calamba, Sapang Malapit Creek in Pasig City, and Mangangate River in Muntinlupa.

“These tributaries collect waste from nearby agro-industrial and residential areas,” the study said.

In particular, Mangangate River has high fecal contamination found in samples collected and analyzed in 2021.

Veteran fisherman Rolando Molera and BFARMC President Benjie Reyes, both longtime residents of Muntinlupa City, have been fishing and monitoring the Laguna de Bay waters near their community. Over the years, they have witnessed significant changes in the lake’s condition. Photo by Cristina Eloisa Baclig

Mangagate, also known as the Alabang-Cupang River, is 10 kilometers long and flows through portions of Alabang on its way to Laguna de Bay.

The Mangangate River was pinpointed by Reyes as one of the possible primary sources contributing to the pollution in the Muntinlupa section of Laguna de Bay. It hosts a number of informal settler houses and was found to be the source of most of the solid wastes that end up in the Muntinlupa portion of the lake.

A Wealth Accounting and the Valuation of Ecosystem Services (WAVES) policy brief from May 2016 reported that the water quality of the Mangangate, a sub-basin of Laguna de Bay, was consistently classified as “BD” or “worse than D” in evaluations conducted in 2003, 2010, and 2014.

This classification indicates a water quality level below Class D, which is suitable only for irrigation, highlighting severe pollution issues.

The policy brief identifies domestic, industrial, and agricultural/forest runoff as key contributors to the degradation of the lake’s water quality, “which are continuously drained to Laguna Lake.”

LLDA blocks data access to identify violators

The LLDA has the mandate to identify who is polluting Laguna de Bay and issue penalties to deter future pollution, yet our attempts to access a list of violators have been blocked. submitted multiple Freedom of Information (FOI) requests to the LLDA between September and October 2023, aiming to identify the entities with the highest number of citations and the industries most frequently caught dumping waste. However, all of these requests were denied.

These requests sought details on Notices of Violation (NOVs) and Cease and Desist Orders (CDOs) issued by LLDA to various entities in the region.

Among the specific details requested were the type and location of establishments and industries penalized by the agency, as well as the reasons for the issuance of NOVs and CDOs.

Despite requests involving non-personal data, LLDA said that it withheld substantial portions of the information due to the Data Privacy Act and the need to protect confidential information.

The agency, however, did not give further explanations on how the requested data violated the Data Privacy Act or the confidentiality provisions outlined by the LLDA.

“No government agency should withhold any public information, especially if the purpose of the request is for public awareness,” progressive fisherfolk organization Pamalakaya stressed.

In-person meetings with the LLDA yielded contradictory reasons for why the requests were denied.

An LLDA official explained that due to the extensive amount of “statistics” requested, they decided not to disclose such data, citing data privacy concerns, not their capacity to pull the requested records.

The official noted that there was an initial attempt to process the requested data.

“I was trying to do it as requested, but it’s quite a lot because our database doesn’t categorize specific types of business activities, and because of data privacy concerns, we cannot provide the names of the industries,” an LLDA official told

“The database only lists the type of industry without grouping similar activities together. I started processing but couldn’t continue because the categories are too diverse, including wood manufacturing, piggeries, slaughterhouses, poultry, among others,” the official explained.

“In the database, each industry needs to be listed individually. I tried to extract all those with notices of violation and cease and desist orders, but it was still a lot. I only managed to do a few hundred at that time,” the official continued, noting that managing the data request was not the only task they had.

The official admitted that they eventually “lost focus” in processing the data request despite initial efforts to compile and release whatever information was permissible.

The denied FOI requests, resulting in disappointing outcomes, are part of a broader issue.

The progressive fisherfolk organization, Pambansang Lakas ng Kilusang Mamamalakaya ng Pilipinas (Pamalakaya), has reported similar experiences with LLDA’s refusal to provide essential data and information.

Pamalakaya told that it has been requesting the LLDA for a cumulative impact assessment of the lake’s aquatic ecosystem in connection to various government and private sector projects.

Among these is the Napindan Hydraulic Control Structure that was built in 1983, which, according to the organization, has resulted in the drastic deterioration of the lake’s fishery resources and the proliferation of private fish pens and other aquaculture structures over the years.

“We can say that the agency’s non-transparency on this crucial information has also been one of the main stumbling blocks that we face as our organization and members across Laguna de Bay pursue its genuine rehabilitation and conservation,” the group stressed.

“No government agency should withhold any public information, especially if the purpose of the request is for public awareness, and if it will be used by people’s organizations and non-government entities to advance the welfare of the environment and the general public,” it added.

COA red flags

A recent audit report identified the LLDA’s failure to effectively manage its resources as a root cause of inability to collect and and disclose comprehensive environmental data.

COA also flagged inconsistencies in LLDA’s enforcement of fines for wastewater discharges and the under-collection of Environmental User Fees. These financial discrepancies significantly affect LLDA’s effectiveness in enforcing environmental laws and could impact the overall efficiency of its operations.

For example, the agency’s inability to collect sufficient fees undermines its financial sustainability and hampers its ability to pay for comprehensive environmental monitoring and enforcement activities. Without good monitoring data, they cannot pursue and fine violators and without the funding from those fees, they cannot further improve their monitoring and response.

The audit further recommended the development of specific policy guidelines to ensure consistent imposition of penalties. Implementing these guidelines could help standardize the enforcement process, making it more effective and systematic.

The implementation of these suggestions would not only solve problems related to the uniformity of enforcement but also improve the LLDA’s transparency by increasing its openness and accountability in decision-making processes that could stop the flood of wastewater entering the lake.

Findings from last year’s COA report highlighted another facet of the management challenges faced by Laguna Lake.

The report points out that private corporations own almost half of the allowable fishing area in the lake, exceeding the designated 40 percent limit set for corporate entities, thereby compromising the allocation that should favor independent and underprivileged fisherfolk.

The 2018 Zoning and Management Guidelines (Zomag) specify that 60 percent of the allocated area, or 5,520 hectares, should be reserved for independent fisherfolk. The remaining 40 percent, amounting to 3,680 hectares, is allowed for corporations, partnerships, and cooperatives.

“We would like to emphasize one of the primary purposes for the systematic and equitable area allocation […] is to rationalize the utilization of the Laguna de Bay area and its resources with due regard to the underprivileged fishermen and their entitlements which LLDA failed to achieve,” COA noted.

It added that the provisions of the Zomag prevail over its implementing rules and regulations after inconsistencies in the document were found, including the lack of distinction between cooperatives and individual fishing operations.

Deadly impact

As the lake water grows dirtier and dirtier, local communities along the lake are the ones feeling the impact.
Aside from being one of the major causes of lake deterioration, Rivera stressed that fecal material from different sources that are discharged into the lake “may contain harmful microorganisms that can cause diseases and thus pose a potential health risk.”

This was echoed by Dr. Rico Ancog, dean of the School of Environmental Science and Management at the University of the Philippines (UP) Los Baños, who noted that “highly infectious pathogens” harbored by fecal matter found in water resources can be transmitted and affect humans in various ways, primarily through ingestion of food and water sources and direct contact with contaminated water.

“Water-borne pathogens are among the most common sources of diseases related to fecal coliform contamination,” said Ancog.

Among major waterborne diseases related to ingestion of water contaminated with fecal coliform include:

“Of these [diseases], the most prevalent modes of transmission are through ingestion and consumption of contaminated food and water resources from the lake that are not processed or prepared hygienically (i.e., fish, kangkong, etc.) and through direct contact with the contaminated water,” Ancog explained.

Globally, at least 600 million, or one in ten people, become sick due to contaminated food, according to the World Health Organization (WHO). It added that at least 420,000 people die every year due to food poisoning.

“Diarrhoeal diseases are the most common illnesses resulting from the consumption of contaminated food, causing 550 million people to fall ill and 230,000 deaths every year,” it said.

Although the Department of Health (DOH) noted a reduction in the morbidity rate due to diarrhea from 1,520 per 100,000 population in 1990 to 347.3 per 100,000 population in 2010, recent years have seen notable outbreaks, which health authorities attribute to a combination of socio-cultural factors and environmental issues.

The significance of these health risks is highlighted by recent data by the DOH on Acute Bloody Diarrhea cases in the Philippines from 2019 to 2022. This data presents a comprehensive view of the ongoing public health challenges:
Regionally, the CALABARZON (Cavite, Laguna, Batangas, Rizal, Quezon) area also reflected these trends. While cases declined for two years during the pandemic, cases picked back up in 2022, reaching 323.

While the fluctuations in acute bloody diarrhea cases underscore significant environmental impacts on gastrointestinal health, typhoid fever introduces another layer of complexity. This enteric disease, also linked to waterborne pathogens, further highlights the broad spectrum of public health issues affected by water quality and sanitation practices. Rates of typhoid fever deaths follow the same pattern.

While the data on Acute Bloody Diarrhea and Typhoid Fever provided by the DOH are not explicitly linked to fecal coliform contamination nationwide or specifically in the regions surrounding Laguna de Bay (CALABARZON), they serve to illustrate the broader impact of waterborne diseases.

These statistics offer insight into the potential health consequences of water quality issues, emphasizing the need for vigilance in monitoring and improving water sanitation to mitigate the spread of such diseases.

Lake resources dwindle

High fecal coliform levels in Laguna de Bay not only pose a risk to public health but also threaten its diverse natural resources and the livelihood dependent on them.

Laguna de Bay hosts an array of life, including 31 fish species across 16 families, 154 phytoplankton species, 36 types of zooplankton, and 24 macrophyte species. Commercially important species such as white goby, mudfish, milkfish, and the freshwater prawn Macrobrachium sp. are vital to both local diets and economic activities.

The lake also supports a variety of endemic and migrating waterfowl, making it a hub of biodiversity.

However, this rich biodiversity is under threat. Ancog noted, “High levels of fecal coliform can indeed affect the health and population of fish and other aquatic organisms in various means.”

“Exposure to microorganisms related to fecal contamination could lead to dire health impacts on fish species such as impaired reproduction and growth, which could result in population decline in fish species, particularly in target species,” he stressed.

Recent data on fishing yields illustrate the possible outcomes of such ecological pressures caused by a rise in fecal coliform levels in aquaculture and municipal fishing activities.

Before the pandemic, Laguna de Bay’s aquaculture production was robust, with fisherfolk hauling in 46,420 metric tons of fish annually. However, by 2022, this figure had significantly dropped to 26,679.76 metric tons.

The situation for municipal or small-scale fishing is similarly alarming. In 2022, the yield plummeted to 32,535.24 metric tons, marking its lowest point in five years and reflecting a decrease of approximately half from its 2018 peak of 64,116.21 metric tons.

The reduction in yields can be visualized in a more tangible way. For instance, if a fisherman in Laguna de Bay was able to fill 464 tubs of fish annually before the pandemic, by 2022, this same fisherman would only be able to fill approximately 267 tubs — a stark reduction highlighting the environmental strain on aquaculture production.

Similarly, in the realm of municipal or small-scale fishing, a fisherman who could have caught around 641 tubs of fish in the peak year of 2018 would find his catch diminished to just about 325 tubs by 2022.

These figures demonstrate the adverse effects that declining water quality and other environmental challenges have had on the traditional livelihoods dependent on the lake.

Despite the general downward trend, 2021 saw an uptick in aquaculture production, which rose to 39,067.32 metric tons from 38,605.43 metric tons the previous year — an increase of about 462 tubs.

However, the same year saw a substantial decline in municipal fishing output, which fell to 42,253.13 metric tons from 57,388.47 metric tons in 2020 — a loss of roughly 15,135 tubs.

These fluctuations in fishing yields, while not directly linked to high fecal coliform levels, underscore the ecological vulnerability of the lake and the economic repercussions for local communities.

As such, they underscore the need for enhanced management strategies to safeguard Laguna de Bay’s natural resources and support the fisherfolk relying on them.

“The lake can still sustain fisheries but is threatened by contamination from pollution,” the LLDA stressed in one of its policy briefings.

Additional factors also constrained fishing operations across the country, according to Pamalakaya.

Travel restrictions and social distancing protocols during the pandemic hindered fishers’ ability to operate, reducing their operating hours and catch. Concurrently, a series of increases in oil prices last year curtailed the fishing days and hours for small fisherfolk.

Pamalakaya also cited the absence or inadequacy of government subsidies, coupled with the ongoing degradation of some of the country’s water bodies due to harmful conversion and reclamation projects, as aggravating circumstances among poor fisherfolk.

Cleanup drives: Efforts to save the lake

Despite these challenges, Reyes highlighted the efforts of the local government and fisherfolk in Muntinlupa, who have been proactive in cleaning their sections of Laguna de Bay. He noted that because much of the pollution originates from estuaries carrying waste from nearby cities, it complicates the local cleanup efforts.

According to the LLDA, another potential source of contamination in Laguna de Bay is the backflow from the heavily polluted Pasig River, which occurs due to tidal fluctuations in Manila Bay.

Cleanup efforts, however, mostly focus on solid waste, not the fecal contamination that presents the real hazard.
In 2023, the LLDA, the Watershed Management Councils, and other partners, conducted cleanup activities in several key locations:

All are among the many tributaries that feed into Laguna de Bay, contributing to the lake’s water system and impacting its overall water quality.

The agency reported that over the course of the year, these initiatives resulted in the removal of 5,792 kilograms of assorted solid waste from these rivers, aiming to improve the condition of these waterways.

This is an equivalent of approximately 386 sandbags, enough to protect critical low-lying areas in the country during seasonal floods.

Photo: Various solid wastes were removed from Laguna de Bay during a clean-up drive. Photo from the Laguna Lake Development Authority
Photo: Various solid wastes were removed from Laguna de Bay during a clean-up drive. Photo from the Laguna Lake Development Authority

In a previous interview with, Hernandez said there are annual cleanup drives in the lake. One of the peak cleanup activities of LLDA usually takes place in the dry season — around April to May — when more water hyacinths or water lilies propagate in the lake.

“We usually do that during summer months because it is easier to transport and gather [the water lillies]. It is also easier to operate the equipment compared when during rainy seasons since the waves and winds are stronger,” Hernandez explained, speaking in Filipino.

Water lilies could cover an entire portion of the lake, which could lead to lower light penetration in the covered water. When this happens, there would be fewer fish in the area — which can affect the livelihood of fishermen.

Hernandez also explained that water lilies, when left to decompose in the lake, will degrade the quality of water in Laguna de Bay.

Aside from water lilies, the LLDA likewise focuses on cleaning or removing filamentous freshwater green algae in the lake, which bloom more during the summer season.

While the algae — also known as pond scum of the genus Spirogyra — does not produce toxins that can make humans and animals sick, it can deplete the oxygen levels in the lake once these algae decompose.

In Muntinlupa alone, residents like Reyes and Ronaldo Molera have commended the efforts of both the local government and the community in maintaining the cleanliness of their waterways despite being the “catch basin” for waste from nearby cities via connecting rivers or streams.

“The LMO often cleans up, so what happens is we end up cleaning up trash from other places,” said Reyes.

“We keep cleaning non-stop. Of course, trash doesn’t come with an address. If it did, say from Las Piñas, perhaps we could send it back, but it doesn’t work like that. Once it gets here, there’s nothing we can do but clean it up,” said Molera in Filipino.

The LLDA outlined its efforts in a 2023 accomplishment report, which highlighted not only ongoing cleanup efforts but also the enforcement of regulations against polluters.

“The monitoring of industries resulted in the issuance of Cease and Desist Orders (CDO) to 9 establishments due to water pollution and for operating without the necessary LLDA Clearance / Discharge Permit (LC/DP),” the agency revealed.

solid wastes

Graphic by ED LUSTAN /

Additionally, LLDA issued NOVs to 924 industrial and commercial establishments. Despite these actions, the LLDA’s report did not specify which industries or establishments were issued with NOVs and CDOs, continuing a pattern of nondisclosure that may mean the eventual death of Laguna de Bay.

Local fisherfolk, such as Molera, meanwhile, seek out alternatives to keep the lake viable. Molera details the support from the local government, including the quarterly stocking of fingerlings, which ensures continued fish availability.

“Our LGU (local government unit) is helping us not to stop production,” he said.

“We find ways to sustain it. We maintain our hatch, release fingerlings, and our mission is always to keep the environment clean,” he added, illustrating a community deeply invested in the lake’s health.

Pagdingalan underscored the resilience of Laguna de Bay. “It is still far [from being declared as biologically dead],” she asserted, signaling that the situation, although serious, has not yet reached an irreversible point.

Molera, meanwhile, embodies the resilience and proactive spirit that bolsters these governmental efforts.

Yet, despite these efforts, challenges persist.

Engineer Jocelyn Sta. Ana, division chief III of the Environmental Laboratory and Research Division (ELRD) of LLDA, has recognized the existing challenges. Despite these issues, she maintains a positive outlook on the fisheries industry’s current situation, noting that it continues to operate within the parameters of the Class C water quality classification.

“Though there are problems in localized areas, generally, Laguna de Bay remains within the Class C classification,” she said, pointing out that the situation, while managed, is not ideal.

Ancog emphasized the need for a comprehensive management approach targeting both direct and indirect sources of pollution.

He stressed the importance of mitigating the impact of fecal coliform contamination on the lake’s marine resources through a variety of strategies, from improved sewage treatment to enhanced regulatory enforcement.

“Implementing these management practices in a coordinated and holistic manner is crucial for safeguarding the ecosystem’s health and supporting sustainable fisheries for future generations,” Ancog noted.

He encouraged the public to engage in preventive measures to reduce health risks associated with high fecal coliform levels:

“By following these preventive measures and staying informed about water quality conditions, the public can reduce the risk of adverse health impacts associated with high fecal coliform levels in Laguna Lake and help preserve the health of the ecosystem for future generations,” Ancog advised.

Urgent balancing act

The LLDA has crafted a master plan aimed at revitalizing the lake’s ecosystem by 2026.

While it acknowledged the deterioration of the water quality in the lake, its proposed management strategy focused only on rehabilitation.

The plan targets “Areas Needing Special Protection,” such as denuded forestlands, encroached shorelands, and heavily silted areas.

Key actions include enhancing water quality through engineered wetland systems, preventing erosion in critical watersheds, managing flood risks with sustainable solutions, and improving the resilience of lakeshore communities

waterborne diseases

Graphic by ED LUSTAN /

The LLDA said this comprehensive approach aims to restore the lake’s ecological health and support sustainable local settlements, including the over 14.6 million people who rely on the lake for essential resources.

Despite the LLDA’s belief that Laguna de Bay remains far from being biologically dead—contrary to earlier predictions that it would perish within 10 to 15 years—it’s crucial to recognize that its tributaries, especially the West Bay, are at risk of severe ecological decline.

Moreover, Ancog stressed that “the presence of such high coliform counts, regardless of subsequent decreases, should not be downplayed as it indicates underlying pollution issues that need addressing.”

Perhaps one that should also not be downplayed is the balance between data privacy and the public’s right to crucial environmental information. This delicate balance is critical when access to necessary data could be pivotal in mobilizing efforts to prevent the lake from facing ecological catastrophe.

“In our database, each industry must be listed individually. I tried to extract all those with notices of violation and cease and desist orders, but it was still a lot. I only managed a few hundred at that time, and that wasn’t the only task I was doing, so I lost focus on that, but I tried to group together what could be grouped,” an LLDA official said in Filipino, explaining the agency’s reluctance to provide the requested data.

When considering the stakes of the lake’s ecological health, the question arises: should the volume of data requests outweigh the urgent need for transparency and action?

Reporting for this story was supported by the Environmental Data Journalism Academy – a program of Internews’ Earth Journalism Network and Thibi.


Fecal coliform data was acquired from the Quarterly Water Quality Reports by the Laguna Lake Development Authority, covering the period from January 2018 to December 2022. Due to the pandemic restrictions, data collection was missed from April to August 2020, and in November 2020, data was not collected due to power interruption caused by Typhoon Ulysses.

A complete list of the steps undertaken in scraping, cleaning, and analyzing the fecal coliform level data can be found on the Data Diary sheet of the DataDoc on Laguna de Bay fecal coliform analysis.

The data on fish production in Laguna de Bay, covering the years 2010 to 2022, was provided by the Laguna Lake Development Authority through a Freedom of Information (FOI) request. The process of data analysis for this data can be viewed in the Data Diary section of the DataDoc on Fisheries production in Laguna de Bay.

For the health-related datasets, data on water-borne diseases in the Philippines—specifically data on cases of Acute Bloody Diarrhea and Typhoid Fever from 2019 to 2022—were collected from the Philippine Integrated Disease Surveillance and Response Weekly Surveillance Report by the Epidemiology Bureau Public Health Surveillance Division of the Department of Health.

This article also used data on the sources of fecal contamination in Laguna de Bay from a study by Windell L. Rivera, et. al, published online in the Journal of Water & Health by the International Water Association.

Another study by Arizaldo E. Castro, et al., published in the Journal of the American Society for Microbiology, was also referenced in this report.

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