Garbage clogging Metro Manila’s waterways remains the primary cause of flooding across the capital region, with thousands of metric tons of waste removed annually from pumping stations and creeks, a top official said.

Metropolitan Manila Development Authority general manager Nicolas Torre III said during the agency’s “Kwentong Kalsada” podcast that the MMDA retrieves about 7,000 metric tons of garbage every year from its pumping stations alone.

Separate cleanup operations in creeks and estuaries removed nearly 5,000 metric tons of waste from January to May this year.

“The flooding problems are because our waterways are clogged with garbage,” Torre said.

The accumulated waste blocks the flow of water through Metro Manila’s drainage networks, causing floodwaters to back up rapidly during heavy rains.

Torre said the MMDA regularly deploys personnel to inspect inundated areas to determine whether clogged drains are the culprit before launching declogging operations.

Flood management has become increasingly difficult because rapid urbanization has left little open ground to absorb rainwater, according to Torre.