Cleaning up Manila’s Pasig River, one tributary at a time


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Jun 30, 2016 | Urban Sustainability | 0 comments

By Anna Valmero

MANILA, Philippines — When the American architect and urban planner Daniel Burnham came to Manila more than a century ago, the Pasig River reminded him of the bucolic Seine in Paris. Burnham likened the Pasig’s many tributaries to the canals of Venice.

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By the 1930s, the comparisons were fading fast. Pollution from residential and industrial waste began to choke the Pasig and its offshoots. It only got worse, thanks to rapid urbanization along the riverbanks, meager infrastructure for handling sewage and weak enforcement against industrial dumping. By 1990, the river was biologically dead. Stripped of oxygen by algal blooms, the smelly river could only support the hardiest species, such as water hyacinths and the pesky “janitor fish.”

For years, uncoordinated efforts to collect trash and dredge silt from the river bottom failed to clean it up. Expensive schemes to aerate the river water by pumping air into it only created more sludge, requiring more dredging.

But a few years ago, officials here finally hit upon a solution that’s showing results. The strategy required thinking on a small scale, not a grand one. Rather than looking for a single bold stroke that would clean up the river, planners set their sights on the Pasig’s 48 small tributaries, or esteros. If they could stop people along these smaller waterways from treating them like open sewers and garbage pits, then they could stem the flow of wastes flowing downstream into the river and ultimately into Manila Bay.

The strategy got its first tryout along one of the most polluted inlets, a 3-kilometer branch called Estero de Paco. It was so successful that it’s become the model for communities along 19 more esteros here. If Manila’s waterways are ever to be restored to what Daniel Burnham saw, it’s going to happen this way: one tributary at a time.

One problem, many impacts

As in cities throughout the developing world, Manila’s water quality problem is not just about the environment. It’s also about flooding, public health and quality of life.

Even during moderate rains here, floating garbage clogs waterways and keeps them from draining properly. Tributaries filled with sediment from organic matter quickly overflow their banks, sending polluted flood waters into riverside communities of shanties.

Manila resident Ruby Cientos works as a ’River Warrior’ to keep Estero de Paco clean. (Anna Valmero)

Manila resident Ruby Cientos works as a ’River Warrior’ to keep Estero de Paco clean. (Anna Valmero)

When Typhoon Ketsana hit the Philippines in 2009, hundreds of people died and much of the capital was submerged for weeks. A leptospirosis outbreak followed, as many people waded for days in waters contaminated with rat urine and garbage. Ruby Cientos, a resident of the village alongside Estero de Paco, recalls how piles of trash that residents had thrown into the water were carried back into their homes during the floods.

The typhoon forced planners to look for new approaches. And it was in Cientos’ neighborhood where they began the search. They set out to see if it was possible to clean up Estero de Paco — and keep it clean. If it worked, maybe the solutions could scale up.

To run a pilot project, the Asian Development Bank tapped the local subsidiary of INCLAM, a water engineering firm based in Spain. The project was carried out with project partners and stakeholders, including the ABSCBN Lingkod Kapamilya Foundation, government agencies, the Pasig River Rehabilitation Commission, schools and other interested nonprofits.

When Angel Gomez, country manager of INCLAM Philippines first visited Estero de Paco in 2013, he found a waterway choked with decaying trash. Both children and adults were practicing open defecation and discarding the waste directly into the water. The creek gave off an assaulting smell. It “looked dead,” Gomez says.

It was. Water testing indicated extremely high amounts of organic matter in the water — a sign of lots of raw sewage. There also were high levels of suspended solids, including oil, grease and coliform bacteria. Even the hardy water hyacinths wouldn’t grow here.

INCLAM held several rounds of meetings with community leaders to understand the root of the problem and the context on how the local community perceived the issue, says Gomez. They found most houses were built without toilets, and those that had them were built without septic tanks to collect and treat the waste. Due to the lack of infrastructure and the general neglect for sanitation, Gomez says, “when people need to get rid of waste, the easiest means is the nearby tributary.”

From the rounds of meetings and visits in the area, Gomez’s team identified two things that required urgent action to rehabilitate the waterway. First, they needed affordable technical solutions to increase the amount of sewage that gets treated before reaching the creek. And second, they needed to raise community awareness about the importance of keeping Estero de Paco clean.

Treatment tanks

On the technical side, the team settled on a solution that is common in in other countries, especially Brazil: “condominial” sewage systems. It’s sort of like a large-capacity underground septic tank that serves many homes. Household wastewater from connected homes collects in the tank and begins to settle. Cooking grease forms into solids that sink to the bottom; these and other solids are removed monthly by Maynilad Water Services, the local water provider.

The remaining wastewater is pumped into a contraption called an “anaerobic baffled reactor.” In another set of tanks, organic matter settles to the bottom as sludge and is removed. A chemical solution is added to rid the remaining water of most of the pollutants. The electricity necessary for this process is generated by solar panels atop the reactor.

A mural along the Estero de Paco footpath reminds residents to keep the tributary clean. (Anna Valmero)

A mural along the Estero de Paco footpath reminds residents to keep the tributary clean. (Anna Valmero)

Finally, this water is released into an adjacent wetland constructed by INCLAM. Vegetation planted here can process and use up the remaining organic substances as nutrients. Once the water finishes passing through here, it is released back into Estero de Paco.

Javier Coloma Brotons, an urban development specialist at the Asian Development Bank, says this approach represented a major change in thinking about Manila’s water problem. “Instead of treating the water within the river,” he says, “the solution must help reduce the pollutants from untreated solid and liquid waste that go into the tributary.”

The biggest hurdle to this strategy is getting households connected to the condominial network. There’s a connection fee of 100 pesos per month — a little more than US$2. That’s more than many families in the neighborhood can afford. About a quarter of the 1,000 homes targeted were connected. Gomez says that’s still “significant” as a starting point. Water testing has shown a significant drop in the presence of organic matter in the water; some wetland plants have begun making a comeback.

The technical improvements required clearing a 3-meter wide easement zone along the estero, which meant relocating some 2,000 families who had been squatting in shanties that in some cases were built right atop the water on stilts. The relocation was headed by a local nonprofit called KBPIP, which had deep roots with the community. Having received the worst of the Ketsana floods, many families were ready to move, says KBPIP’s Melvic Cabasag. They went to homes managed by the National Housing Authority in nearby provinces outside Manila, where they received livelihood and job-skills training.

Once the easement zone was cleared, the collection points for the condominial sewage system were built. A footpath was paved along the estero and fruit trees were planted to help stabilize the riverbank. Those improvements not only added protection against future flooding but also increased the amount of green space in the tightly packed neighborhood.

Role models

Around 8 o’clock in the morning, 57-year old Armando Panganiban can be seen riding a small raft around Estero de Paco and scooping out plastic bags and other trash.

Panganiban is a “River Warrior,” part of a corps of residents who patrol the waterway and keep it trash-free. They not only zip around Estero de Paco in rafts but also sweep the footpath and keep the riverbanks clean.

At first, the River Warriors were volunteers. Now, they have been trained and deputized as “environmental aides” who earn a monthly salary of 8,000 pesos, or about US$175. They work for the Pasig River Rehabilitation Commission, a public-private partnership engaged in the broader river cleanup efforts.

“The River Warriors are like the guardians of the estero,” Panganiban says.

Trash collection has been implemented in a market that used to dump garbage in the creek. (Anna Valmero)

Trash collection has been implemented in a market that used to dump garbage in the creek. (Anna Valmero)

Officially, there’s a no-littering policy along Estero de Paco. As a practical matter, it will take some time for old habits to change. The River Warriors’ very presence is part of the effort to make that happen. In addition to patrolling the area and picking up trash, the workers also do regular house visits to remind families to take trash to designated collection points where trucks pick it up three mornings per week.

“People won’t throw their trash into the estero if they see us,” Panganiban says. “Some still do, but it is much less than before.” Panganiban says he once scooped a fetus from the waterway.

There have been other efforts aimed at culture change. On walls alongside the estero, community members painted murals whose message is to keep the waterway clean. The local youth also staged a theater performance depicting a garbage monster from the dirty estero; the people defeated the monster by cleaning up the water.

Still, it’s hard breaking bad habits and forming new ones. That’s most obvious on weekends, when the River Warriors aren’t on duty and plastic bags and bottles begin showing up, floating on the water. Change is happening but it’s happening slowly, says 47-year old Gloria Hernandez, another River Warrior.

“The biggest challenge,” Hernandez says, “is how to change the mindset of the people that the estero is not a dumpsite where we can throw waste and just forget about it.”

Scaling up

The Estero de Paco cleanup finished last year. Aside from the obvious reduction in trash floating on the water and the generally improved look of the area, there have been other benefits. The foul odor of decomposing trash is for the most part gone. Ruby Cientos, who also serves as a River Warrior, says it seems like people around here — especially the young and elderly — aren’t coughing or suffering asthma attacks as much as they used to.

Cientos also says neighbors enjoy using the new footpaths and often bump into each other and chat while out walking.

A new riverbank pathway provides open space prevents flooding. (Anna Valmero)

A new riverbank pathway provides open space prevents flooding. (Anna Valmero)

The project “connected the people in the neighborhood into a community and the quality of life improved,” Cientos says. “Young kids can play here and people get out to chat with neighbors, too.” A study by a local Catholic school in the area cited the same benefits and noted that petty crimes reported in the area had gone down.

Importantly, the area appears to be much more resilient to flooding. In a country that gets hit by an average of 20 typhoons per year, these tests come frequently. Over the past year, heavy rains have flooded some parts of Manila but the neighborhood around Estero de Paco fared well.

“The main benefit of the Estero de Paco project is creating a flood-free environment,” says Miko Aliño with the ABSCBN Lingkod Kapamilya Foundation, who was involved with the resident relocation piece of the project. “Residents no longer have to worry about evacuating their homes or staying in the upper floors during heavy rains.”

According to the Pasig River Rehabilitation Commission, communities along 19 other tributaries in Metro Manila are now following the example of Estero de Paco. The commission says that with this and new efforts to come, all 48 tributaries of the Pasig could be cleaned up by 2019. Cientos, who is 37, is optimistic that she will be able to see a clean Pasig River in her lifetime.

“Ten years ago, before the rehabilitation, I thought it was impossible to see the sky reflected on the estero waters,” she says. “Now, the water is free of floating garbage. That’s a good source of inspiration to keep on doing what we have started.”


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