President Ferdinand R. Marcos Jr. on Friday directed a study on the building of weirs along tributaries to control the water flow from Sierra Madre down to Rizal and Metro Manila.
The unimpeded water flow causes severe flooding during the rainy season, according to the President.
“Iyong weir kasi — pagka wala namang tubig, like now, sinasabi ni (Rizal) Governor (Nina Ricci Ynares), wala ka nang makitang tubig doon sa ilog. So, bakit pa tayo maglalagay ng dam. If there’s a weir pinapadaan niya ang tubig pero mayroon siyang binabagalan ‘yung takbo,” President Marcos said during a situation briefing in San Mateo, Rizal on the effects of Typhoon Carina and Habagat.
“I don’t see a weir here in this country which is parang bagay na bagay sa atin ‘yun. It’s a weir, called w-e-i-r, weir. Maybe it’s applicable here in the Philippines. I think it might be because I’ve seen it in other places and although the water passes, mababa ‘yung tubig dito sa baba, mas mataas ‘yung tubig doon sa taas. Pero dumadaan ‘yung tubig, pati isda nakakadaan,” he said.
A weir is a small barrier built across a stream or river to control and raise the water level slightly on the upstream side, essentially a small-scale dam.
It is used to prevent flooding, measure water flow, and hold water. The impounded water can be used in towns, homes, industry, or irrigation.
A weir generally allows the water to flow over the crest (which is the top) or sometimes underneath some sections. On the other hand, dams mainly allow water flow to be regulated or controlled by gates or spillways.
During the briefing, Public Works and Highways Secretary Manuel Bonoan told the President that the previous plan was to build the Marikina Dam to control floodwaters from Sierra Madre but it has been reconsidered because of the construction of Wawa Dam.
“So, our plan is to build a series of small dams sa ibaba ng Wawa Dam so that itong mga floodwaters na ito will be impounded,” Bonoan said.
Rizal local officials acknowledged the importance of the Wawa Dam construction, which has greatly mitigated flooding in the province during the typhoon and Habagat.
During its inauguration, officials expected the dam to be filled with water in six months. But it was almost filled with rainwater in just two days, noting the recent high precipitation level.
Without the dam, San Mateo, Montalban, Marikina, Pasig, and parts of Quezon City could have been flooded, they said. PND
Comments