THE largest inland body of water in the Philippines and third largest freshwater lake in Southeast Asia, the Laguna de Bay, may soon emerge as an alternative source of raw water to meet the ever-increasing demand for clean, drinking water in Metro Manila and nearby provinces.
Maynilad Water Services Inc. and Manila Water Company Inc., the private water service providers in Metro Manila, and Metropolitan Waterworks and Sewerage System (MWSS) concessionaires are already tapping into its vast natural water resource.
However, like most bodies of water in the Philippines, Laguna de Bay’s sustainability is currently facing an enormous challenge. Environmental degradation, plastic pollution and chemical poisoning are aggravating the decades of abuse and neglect, prompting key players in the water sector to renew the resounding call for its massive rehabilitation to maximize its economic potential.
AN endeavor similar to the Boracay Action Plan to rehabilitate, protect and preserve the biodiversity of Laguna de Bay and ensure its sustainable development is being proposed by various stakeholders.
The Annual Million Trees Challenge, a movement initiated by former MWSS Chairman and Administrator Rey Velasco, and Million Trees Foundation Inc. (MTFI) Executive Director Melandrew Velasco are backing calls for such initiative.
“What we need is to create a special task force that will take the lead and implement the massive rehabilitation of Laguna de Bay, the way it was done in Boracay and now being done in Manila Bay,” the former MWSS chief said.
MTFI’s Velasco added that a “massive” tree-planting activity involving various national government agencies, local government units, academe, scientific community, church, youth and local government units is needed.
This, he said, will help Laguna de Bay recover from environmental degradation, allowing it to provide the ecosystem services, including defense against natural calamities, which it used to deliver.
He said degraded forest areas around Laguna de Bay should be rehabilitated and planted with a combination of indigenous or native trees, including bamboo, while removing garbage and other debris in the now heavily silted portions of the lake itself, thus reviving the entire watershed.
WITH its multiple uses, the Laguna de Bay Action Plan must identify key result areas and enlist the collaboration and partnership of all stakeholders.
The challenges confronting Laguna de Bay call for a holistic solution. Aside from poor water quality due to pollution, it suffers from decreasing water-holding capacity, and its denuded watersheds need to be reforested.
“Rather than investing additional funds to keep upgrading our treatment technology, we think the more sustainable option is to protect the lake,” Maynilad President and Chief Executive Office Ramoncito S. Fernandez said. “Maynilad’s water treatment capacity can be affected by the varying water quality of the lake,” he explained.
Benefits it brings
LAGUNA de Bay has multiple uses and benefits.
It is home to a variety of fish species, mollusks and crustaceans. It is currently the biggest aquaculture hub in the country, supplying wet markets in Metro Manila and surrounding towns and provinces with affordable fish, such as tilapia and bangus, an important source of protein.
It is also used as a transport route, a source of animal feed, and provides water for irrigation and hydroelectric generation as well as domestic water supply.
Water supply capacity
ACCORDING to the Laguna Lake Development Authority (LLDA), it has a total volume of 3.2 billion cubic meters, a shoreline of 220 kilometers and an average depth of 2.5 meters.
Its waters come from rivers and streams, rainwater, storm water runoff, and sewage.
Laguna de Bay is the catch basin of industrial and domestic wastewater pollution coming from the areas that border the lake among the provinces of Laguna, Rizal and the Metropolitan Manila cities and municipalities.
Several rivers and streams, 22 of which are significant river systems, drain into the lake. The Napindan Channel is the only outlet that drains lake waters into Manila Bay through the Pasig River.
Failed rehab attempt
A PREVIOUS attempt by the government during the term of then President Gloria Macapagal-Arroyo, through the Department of Environment and Natural Resources (DENR), and a Belgian company, Baggerwerken Decloedt En Zoon (BDC), to rehabilitate Laguna de Bay was scrapped in 2011 by the late President Benigno S. Aquino III.
The project was intended to dredge Laguna de Bay and increase its depth to meet global standards for harvesting lake water for purification. Laguna de Bay’s water quality belongs to Class C and is unfit for human consumption without treatment.
The project also called for the creation of navigational channels. The project, unfortunately, was scuttled, sparking controversy and dragging the country to an international arbiter for which it paid dearly.
Huge water potential
THE potential of Laguna de Bay as a source of potable water is enormous. With the service area of the MWSS located within the Pasig-Laguna de Bay river basin, it is a viable water source for its concessionaires. Harnessing the lake’s water for domestic consumption entails investing in technology.
In 2011, Maynilad formally unveiled its Putatan Water Treatment Plant. The treatment plant taps Laguna de Bay as an alternative water source to Angat, the primary water source of MWSS concessionaires. In April 2019, Maynilad inaugurated another water treatment plant in Barangay Putatan.
However, the water treatment facilities’ production capacity has been adversely affected by the raw water quality of Laguna de Bay, especially during periods when algal blooms occur.
REPEATED episodes of algal blooms can be an indication that a river or lake is being contaminated, or that other aspects of a lake’s ecology are out of balance.
The LLDA, in its advisory on algal bloom, stated that in Laguna de Bay, the algal bloom is a periodic occurrence—in the Central Bay and West Bay—where Muntinlupa City is one of the lakeshore’s local government units.
While algal blooms are natural occurrences, their acceleration can be triggered by human activity. Algal blooms arise from shifts in the nutrient balance of the lake water resulting from chemical/industrial/agricultural waste/leachates.
These algal blooms also impact water production.
It can be recalled that an algal bloom in Laguna de Bay that happened in June 2019, when the maximum algal bio count reached 13,230 counts/mL, affected Maynilad’s water production.
DESPITE the current predicament confronting Laguna de Bay, various stakeholders remain hopeful.
In fact, Maynilad is currently constructing a new water treatment plant in Poblacion, Muntinlupa, which will also get raw water from Laguna de Bay.
It is designed to produce 150 million liters per day and is targeted for completion by 2023. Once operational, this new facility will produce a “buffer” supply so that Maynilad can sustain water services despite sudden shifts in the raw water quality of Laguna de Bay.
Image credits: Contributed photos