The government in cooperation with Japan International Cooperation Agency (JICA) plans to pursue the implementation of the Parañaque Spillway project to protect low-lying communities in Metro Manila from massive flooding.
DPWH, together with representatives from the National Economic and Development Authority, Department of Finance and the JICA mission group held a fact-finding meeting for the planned Parañaque Spillway project.
Manuel Bonoan, DPWH secretary, said flood damage in the Laguna lakeshore area during rainy season and due to the effects of climate change is a situation that could not be further ignored.
The discussions focused mainly on the project’s proposed timelines, possible financing scheme and environmental and social considerations, DPWH said in a statement.
Emil Sadain, DPWH senior undersecretary, said the Parañaque Spillway is a much needed engineering intervention to address extreme flooding by draining excess water from the 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, he said.
To control the water level of Laguna Lake, DPWH is proposing the construction of an underground drainage channel to catch overflowing flood water from Laguna Lake before it pumps out to Manila Bay.
The project 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 meter per second.
A deep tunnel technology will have an inner diameter of 13 meters with a tunnel depth that ranges from 50 to 77 meters from the existing ground with a total tunnel length of 10.5 kilometers.
The underground structure will connect Laguna Lake to Manila Bay and avoid spilling of the lake water into low-lying communities. The project will traverse 50 meters below underground the cities of Muntinlupa, Parañaque, Las Piñas, and Bacoor City in Cavite.
