National Irrigation Administration (NIA) chief Ricardo Visaya on Tuesday insisted that the Magat Dam’s opening of the water gates was not the major cause of the massive flooding in Cagayan and Isabela.
The House joint panel is currently conducting investigations on the massive flooding in Cagayan Valley during Typhoon Ulysses.
During the inquiry, Visaya showed a matrix which indicated that from November 9 to 14 amid the typhoon, the peak water inflow at Magat Dam was at 7,128 cubic meters per second. Still, the dam released only at 6,706 cubic meters per second.
Meanwhile, Buntun Bridge’s water level, which measures Cagayan River’s water level, was at 13.2 meters, Visaya added.
The NIA chief said that looking at the matrix alone, he could already conclude that the opening of Magat Dam’s water gates was not the primary cause of flooding in Cagayan and Isabela.
“Can we draw now a conclusion from this matrix? Yes. Is it really Magat Dam that provided or the major cause of the flooding in Cagayan? I don’t think so,” he said.
“Nakita natin, it’s very clear that ‘yung contribution ng Magat Dam sa flooding ng Cagayan was not really the major cause,” he added.
Visaya also insisted that those who would be affected by the water release were warned ahead of time.
Magat Dam not major cause of massive flooding – NIA
“Six hours before release, activate the warning stations. As much as possible, hindi tayo magre-release ng tubig in any dam after 5 o’clock. Ang tina-target natin dito 3 o’clock. We are giving a lead time to all concerned including government offices, LGUs, radio stations, et cetera, six hours para makapag-react sila,” he said.
“Redundant ang pag-iinform natin dito. And it is followed by a black and white document. Lahat ng LGUs pumipirma nito. Kaya hindi nila masasabi na hindi sila nai-inform because we have the documents,” he added.
At the same time, the NIA chief said that the release of water from Magat Dam was done gradually and not all at once.
“During the typhoon, [there is] regulation of outflow from the dam to mitigate damage to the downstream. Nire-regulate ‘yan. Hindi ibig sabihin na during that time, biglang nag-release. Mali ‘yun,” he said.