Aerial shots show the floodwater entering the Upper Wawa Dam reservoir and how the dam’s controlled impoundment reduced the impact of flooding caused by typhoon "Carina".
Government officials have cited the big contribution of the Upper Wawa Dam in reducing the impact of the flooding caused by Typhoon “Carina”, especially in low-lying areas of Rizal province and eastern part of Metro Manila.
The Upper Wawa Dam was a result of the joint venture agreement with the Prime Infra-led WawaJVCo Inc., which currently develops and operates the Wawa Bulk Water Supply Project. The Phase 2 of the infrastructure project is the Upper Wawa Dam,
In a briefing with President Marcos on the impact of “Carina”, Rizal Gov. Nina Ynares said the flooding would have been worse had it not been for the Upper Wawa Dam which helped in impounding water that was supposed to sweep the low-lying parts of the province.
“Mr. President, some time this month, we were together during the inauguration of (Upper) Wawa Dam. We saw it was empty and (they said) it would take six months for them to fill it up...Without it, I feel that, most likely, San Mateo and Montalban would be down; and definitely, Marikina and parts of Quezon City and even Pasig would be affected,” said Ynares during the briefing.
“The Upper Wawa Dam project by WawaJVCo has significantly reduced the effects of flooding in comparison to previous occurrences,” she added, through the presentation of the situation in Rizal by the provincial government to Marcos.
While designed as a water supply dam, the project can also help mitigate flooding in downstream communities.
The Upper Wawa Dam began impounding its reservoir on July 10, an occasion that was attended by the President himself.
National Irrigation Administration (NIA) Administrator Eduardo Guillen affirmed the role of the Upper Wawa Dam in reducing the impact of flooding in Metro Manila.
“Iyan ang kagandahan sa sinasabi ng ating Pangulong Ferdinand Bongbong Marcos Jr., na iyong water management, para kapag tag-ulan, maka-mitigate din ng baha kapag nag-iipon tayo ng tubig (That’s what President Marcos has been saying on the importance of water management so that during heavy rains, it could mitigate the impact of the flooding) said Guillen.
“Like in the case of Metro Manila, there’s the (Upper) Wawa Dam, The destruction would have been worse with the absence of (Upper) Wawa Dam because a huge volume of water was impounded there,” he added.
The Upper Wawa Dam features a reservoir of about 450 hectares, approximately twice the size of Bonifacio Global City, and can store up to 120 million cubic meters of water.
It is the largest dam to be built in over 50 years, with the critical objective of addressing water supply security in Metro Manila and the province of Rizal.
Based on measurements conducted throughout July 24, the floodwater entering the dam’s reservoir peaked at approximately 2,100 cubic meters per second (m3/s).
The controlled impoundment successfully managed the discharge downstream to approximately 200 m3/s, significantly lessening the impact of the floods by a factor of 10.
The Upper Wawa Dam reservoir accumulated over 90 million cubic meters of water during the super typhoon. This helped to mitigate downstream flooding, contributing to the protection of lives and property.
The Upper Wawa Dam will start to supply bulk water by the end of 2025.
WawaJVCo said it will continue collaborating closely with its host communities to help strengthen resilience against future weather-related challenges.
The Prime Infra-led company said it remains steadfast to building better lives and resilient economies through critical infrastructure, ensuring that its projects are environmentally resilient and socially relevant.