
West Zone concessionaire Maynilad Water Services, Inc. (Maynilad) is ramping up its wastewater operations this rainy season to prevent sewer overflows and support flood mitigation, while continuing its year-round efforts to maintain a clean and efficient sewer network.
While Maynilad’s wastewater operations run year-round, the company deploys additional teams and intensifies sewer inspections and declogging activities during the rainy season to address increased risks of blockages and overflows.
These activities are especially critical in areas with combined or hybrid sewer systems, where stormwater mixes with wastewater, often bringing in trash and debris that can clog interceptor boxes, manholes, and sewer lines. Interceptor boxes are installed at the end of drainage lines to catch combined flows and divert wastewater to Maynilad’s sewer network for proper treatment.
As of June 2025, Maynilad has cleaned over 285 kilometers of sewer lines and cleared more than 3,500 sewer manholes. Preventive maintenance ensures that wastewater is conveyed properly to treatment plants and prevents sewer overflows that may worsen during heavy rains.
“Interceptor boxes are installed at the end of drainage lines to catch combined flows and divert wastewater to our sewer network for proper treatment,” Maynilad Wastewater Management Head, Engr. Zmel Grabillo explained. “Unfortunately, these systems can get blocked by trash that’s swept into drainages during floods.”
Maynilad has prioritized combined-sewer areas such as Quezon City, Pasay, Parañaque, and Valenzuela, where more frequent maintenance is needed during the wet season.
Although Maynilad does not clean storm drains—which fall under the jurisdiction of local government units—its work in maintaining the sewer network helps ease pressure on drainage systems, indirectly contributing to flood prevention.
The company continues to coordinate with LGUs and other stakeholders to protect sewer infrastructure and ensure public health and environmental safety.
“We ask the public to be responsible with waste disposal,” Engr. Grabillo added. “Even small acts like properly segregating trash can help prevent blockages that cause flooding.”
Maynilad is the largest private water concessionaire of Metropolitan Waterworks and Sewerage System (MWSS) in the Philippines in terms of customer base. Its service area includes the cities of Manila (all but portions of San Andres and Sta. Ana), Quezon City (west of San Juan River, West Avenue, EDSA, Congressional, Mindanao Avenue, the northern part starting from the Districts of Holy Spirit and Batasan Hills), Makati (west of South Super Highway), Caloocan, Pasay, Parañaque, Las Piñas, Muntinlupa, Valenzuela, Navotas, and Malabon, all in Metro Manila; and the cities of Cavite, Bacoor, and Imus, and the municipalities of Kawit, Noveleta, and Rosario, all in the province of Cavite. (PR)