La Mesa Dam alert raises flood threat amid Habagat rains

Floyd Brenz., Philippine Canadian Inquirer
August 18, 2026

Photo Courtesy: PNA

Philippines — The rising water level at La Mesa Dam is putting several low-lying communities on heightened alert as continuous rains from the Southwest Monsoon or Habagat continue to affect Metro Manila.

The Quezon City Disaster Risk Reduction and Management Council placed La Mesa Dam under Alert Level 3 after its water level reached 79.71 meters as of 5 a.m. on August 18.

Authorities warned that excess water from the dam could affect communities along the Tullahan River, including Fairview, Forest Hills Subdivision, Quirino Highway, and San Bartolome.

Other major waterways in Metro Manila are also being closely monitored. The Marikina River was recorded at 14.98 meters, while the Tullahan River stood at 38.44 meters and the San Juan River at 11.97 meters. No alert level was reported for the three waterways at the time of monitoring.

The elevated water levels come as Habagat continues to bring heavy rains over Metro Manila, with PAGASA forecasting 50 to 100 millimeters of rainfall in the region.

Residents in flood-prone and low-lying communities are urged to remain vigilant, monitor official advisories, and be prepared to evacuate if water levels continue to rise.