MANILA -- An expert said there is a need for local government units (LGUs) to invest in anaerobic digesters - tanks where microorganisms break down biodegradable waste into useful material - to improve solid waste management (SWM) nationwide.

"Long-term SWM investments will help turn biodegradables into organic fertilizer and biofuel while protecting the environment and reducing the volume of trash for disposal," said Eligio Ildefonso, executive director of the National Solid Waste Management Commission (NSWMC) Secretariat.

Ildefonso stressed the urgent need for anaerobic digester investments stems from the increasing volume of waste, as well as the government crackdown on illegal dumpsites and the permanent closure of the Payatas sanitary landfill where Quezon City had been dumping its trash.

The government target to increasingly divert waste from landfills increases this urgency, he added.

According to experts, anaerobic digestion is a biological process that occurs naturally when microorganisms break down organic matter in environments with little or no oxygen.

Data from the Environmental Management Bureau (EMB) indicate the extent of biodegradable waste and the potential for harnessing the anaerobic digestion process in several Metro Manila LGUs.

The data showed that biodegradables account for the bulk of waste in the cities of Caloocan (48.6 percent); Mandaluyong (46 percent); Marikina (46.54 percent); Pasay (41.20 percent); Quezon (54 percent); Taguig (52.37 percent); and Valenzuela (46 percent); as well as the municipality of Pateros (57.46 percent).

Biodegradables also form a significant part of waste in Las Piñas (27.73 percent); Makati (36 percent); Parañaque (28.36 percent); and Pasig (38 percent).

The volume of waste Metro Manila LGUs dispose of daily varies from 487 cubic meters in Las Piñas to 3,507.7 cubic meters in Caloocan, according to the EMB data.

"LGUs can reduce the volume of waste for disposal by turning biodegradables into organic fertilizer and biofuel through anaerobic digestion using proper facilities," said Ildefonso, noting that locally available basic anaerobic digesters cost about PHP1 million each.

To meet financing requirements, he said several barangays could form a cluster and pool their funds to purchase an anaerobic digester for their common use.

"That will be more practical and cost-effective in the long run than transporting all waste to sanitary landfills," he said.

The Department of Environment and Natural Resources (DENR) earlier announced plans to close down a total of 500 illegal dumpsites nationwide before 2022, with more than 50 of them due to be closed this December.

The department warned that it would file charges against local officials who would allow the operation of illegal dumpsites in their areas of jurisdiction.

Such moves are aligned with the intensified implementation of Republic Act 9003 on Ecological Solid Waste Management.

Last month, the DENR also rejected Quezon City's request to reopen the Payatas sanitary landfill until December due to various environmental violations in the dumpsite and its susceptibility to trash slide.

With Payatas' closure, the NSWMC noted that Quezon City can opt to bring its garbage to the sanitary landfills in Rizal province's Rodriguez and San Mateo municipalities as well as in Pampanga province's Clark area and Bulacan province's Norzagaray municipality.

Taguig City Mayor Lani Cayetano recognizes the need for more cost-effective SWM measures, noting that hauling waste in her area of jurisdiction is becoming "overwhelmingly expensive".

She said Taguig collects an average of 550 tons of waste a day, mostly from restaurants in high-end Bonifacio Global City.

The budget for such waste can be used for other services, she said at the Third Integrated Ecological Waste Management Expo in Metro Manila last month.

NSWMC and EMB decided to spearhead the expo in partnership with the interior department, Metro Manila Development Authority, Quezon City and Taguig City to help raise public awareness about SWM.

The partners also sought the promotion of lifestyles that support sustainable products and practices.

Various products exhibited at the expo demonstrated the possibilities from practicing SWM, such as household and fashion accessories, as well as one-of-a-kind outfits made of materials that can be recycled and reused.

Recycling and reusing materials are among the SWM measures being promoted by the government. (PNA)