MANILA — The Department of the Environment and Natural Resources (DENR) on Wednesday said firms must also consider the "Big One" and the threat of tsunamis in their reclamation projects, as the agency undertakes a cumulative impact assessment on these.

Environment Secretary Toni Yulo Loyzaga said sea level rise and various geological events "needs to be considered" when it comes to reclamation.

Trenches and faults are two earthquake generators that can generate tsunamis, according to Phivolcs.

"On the geological hazards: So far ang nakikita ko pa ngayon in terms of the studies I have looked at for reclamation projects is the reference on the 7.2 movement sa West Valley Fault," Loyzaga said in a Palace briefing.

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"Mayroon po tayong tinatawag na Manila Trench. Ito ay nandiyan sa Manila Bay. That is the geological event we are looking at in terms of a generation of a potential tsunami. So yun, hindi ko pa nakikita sa mga studies na sinubmit ng mga proponents," she added.

The DENR chief noted that should a 7.2-magnitude earthquake dubbed the "Big One" hit Metro Manila, it will "generate some movement in the waters" and may affect efforts to provide help.

"The rescue and the relief operations were meant to come by air and by sea. So reclamation projects could possibly have an impact on that plan sa inyo, you could look up Oplan Metro Yakal Plus," she said.

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Loyzaga, however, cited some values that some reclamation holds in terms of the economy.

This was why a cost-benefit analysis is important in terms of its impact to the ecology. To do this, the DENR is currently undertaking a cumulative impact assessment on reclamation projects, which would be predominantly composed of Filipino scientists.

She earlier said they are reviewing the compliance of the projects that already started. There are 22 reclamation projects in the Manila Bay, the Philippine Reclamation Authority said.

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