THE government revived the planned Parañaque Spillway Project (PSP) in a bid to protect low-lying communities in Metro Manila and nearby provinces from massive flooding.

Public Works and Highways Secretary Manuel Bonoan said on Tuesday that the government sought the support of the Japan International Cooperation Agency (JICA) to finance the ambitious project, which was first eyed for implementation during the Arroyo administration following the onslaught of Typhoon “Ondoy” that inundated Metro Manila.

Officials of the Department of Public Works and Highways (DPWH), National Economic and Development Authority, Department of Finance, and JICA mission group recently held a fact-finding meeting for the PSP flood control project to address the perennial flooding problem in Greater Manila and the nearby provinces of Laguna and Rizal.

Bonoan said that flood damage in the Laguna lakeshore area during the rainy season due to the effects of climate change is a situation that could not be further ignored.

Public Works Senior Undersecretary Emil Sadain said the PSP is a much-needed engineering intervention to address extreme flooding by draining excess water from Laguna Lake into Manila Bay.

Using underground tunnel technology, this flood control option for the Laguna de Bay basin is based on the comprehensive flood management plan supported by surveys carried out by JICA experts, added Sadain.

To control the water level of Laguna Lake, DPWH proposed the construction of an underground drainage channel to catch overflowing flood water from Laguna Lake before it is pumped out to Manila Bay.

The Parañaque spillway involves the construction of an open channel and tunnel with the inlet at the land side in Buli (south side of Sucat) and with the outlet at the Zapote River mouth with a maximum outflow discharge of 240 cubic meters per second.

It will have a deep tunnel technology with an inner diameter of 13 meters having a tunnel depth ranging from 50 to 77 meters from the existing ground with a total tunnel length of 10.50 kilometers.

The underground structure that will connect Laguna Lake to Manila Bay will avoid the spilling of lake water into low-lying communities. The project will traverse 50 m underground the cities of Muntinlupa, Parañaque, Las Piñas and Bacoor in Cavite.

With this, the DPWH will be able to mitigate the inundation in the Laguna de Bay Lakeshore area by draining the water lake directly into Manila Bay.

The DPWH, which is mandated to implement the infrastructure development projects, including the flood control works, has identified the PSP project as one of the priority projects in the Philippine investment plan.

The project was proposed to be funded under a JICA loan.