Written by Manuel T. Cayon / Mindanao Bureau Chief
DAVAO CITY – Filipino scientists working on a project to evaluate climate hazards would start mapping out the Compostela Valley towns of New Bataan and Monkayo, using a precision light-detection mapping gadget attached to a single-engine airplane.
Seventeen Filipino engineers, geologists and climate scientists from the University of the Philippines and other government agencies were scheduled to start their aerial-borne light-detection and ranging (Lidar) mapping project of the two towns, to generate light-coded images of the topography of the area, and identify actual and potential hazard areas.
Dr. Elsie Solidum, assistant regional director of the Department of Science and Technology (DOST), said the team was part of the entire unit of the Disaster Risk Exposure Assessment for Mitigation (Dream)-Lidar project that would map out the major river tributaries in the country.
The Dream Lidar was launched on Nov. 22 last year, with demonstration on how the light-resonating gadget would generate fine details of the topography of the locality, identifying rivers and waterways, faultlines, forest resources and the terrain of the area in color-coded images.
The project was supposed to start mapping in Luzon, then down to the Visayas and Mindanao, starting with the areas around Clark in Pampanga, where the Lidar gadget was launched.
But with super Typhoon Pablo creating what scientists described as “phenomenal” and “unprecedented” distortion of the terrain, project scientists decided to forego with the schedule to study the changes on the main river in New Bataan and Monkayo, which flattened and dispersed the water channel.
“What was once a single river [flowing from the Andap mountains to the rest of New Bataan] with deep channel is now spread of small streams with big boulders in the previous river way,” she said.
For scientists, she said, “these are events or situations that usually dictate them to immediately conduct a study. It’s like the phenomenal eruption of Mt. Pinatubo.”
The Lidar gadget is an instrument that photo-scan the terrain of a place, generating color grids that indicate slopes, mountains, valleys, rivers and forests, she said.
“The resulting topography map would allow us to pinpoint water sources and channels, and pinpoint potential hazards of water flow, possible mud flow and landslides,” she said.
While the regular mapping would use the bigger scale ratio of 1:50,000 meters, such as the geohazard map of the Mines and GeoSciences Bureau, and the Google Earth at 1:5,000, the Lidar-generated map would be finer detailed at 1:20 centimeters.
“With the mapping gadget attached to an airplane, the mapping would better present an area than the usual ground-based mapping,” she said.
The team would spend 10 days mapping the two towns, and was likely to resume their work plan of starting in Luzon down to Mindanao.
The P1.8-billion Lidar project estimated 500 “flying days” to finish mapping the major river tributaries in the country. Solidum said the resulting map would still be subject to validation from another ground-based study.
She said the Lidar map would have other crucial and more important uses including forest inventory (determining forest cover), environmental monitoring, infrastructure mapping and faultline mapping.
“These would be a lot important to policy-makers, disaster risk-reduction teams, local governments, students and scientists,” she said.
The Dream Lidar project is a component activity under the Project National Operational Assessment of Hazards of the DOST.