Potential Danger of the Laguna Lakeshore Expressway Dike
A potentially devastating threat looms over the proposed Laguna Lakeshore Expressway Dike (LLED) should it be built. According to experts, a major earthquake in the West Valley Fault could rupture the dike and lead to a catastrophic flood.
The LLED is proposed to run from Taguig in Metro Manila to Calamba and Los Baños in Laguna. It will be 47 kilometers long, with a six-lane dike that has bridges, pumping stations and ancillary flood gates. The project will also involve 700 hectares of reclaimed land. The project aims to provide commuters with an alternative route between Metro Manila and Laguna as well as mitigate flooding for communites along Laguna Lake.
However, University of Illinois professor emeritus Dr. Kelvin Rodolfo warns that a rupture in the dike would cause a massive flood in Manila Bay, stating that this could happen with or without a seiche. A seiche is described as standing waves set up on rivers, reservoirs, ponds, and lakes when seismic waves from an earthquake pass through the area. Rodolfo also pointed out that reclamation of land would actually worsen floods in the area instead of mitigating them, as it reduces the size of the nearby body of water making it fill up faster. “The worst-case scenario is, if this (earthquake) happens at the height of the rainy season with a very full lake, it is accompanied or succeeded by a series of seiches, and it happens at night,” Rodolfo said.
Scientist have stated earlier that a 7.2 magnitude earthquake is due in the West Valley Fault.
