Estimating Earthquake Risks: A Case of Rapid Earthquake Damage Assessment System (REDAS) Application in the Province of Isabela, Philippines

Authors

  • Cesar Vallejo

Abstract

Disastermanagement has always been one of the major challenges in achieving a disasterresilient &more safe communities. Natural hazards are always present in our lives like floods, typhons,
earthquakes,landslides, tsunami, droughts,volcanic eruptions, and many othersaggravated by changing
climate. Moreover, poverty, a vulnerability condition, fast growing population, increase in population
densities, urbanization, pollution and degradation of our environmentincrease disaster risks and had add up
to complexities of disaster management.
This study aimed toassess earthquake risks using the Rapid Earthquake Damage Assessment System
(REDAS) for three pilot barangays in Ilagan City, Isabela namely: Calamagui I, Calamagui II and Alibagu.
The latter is the seat of provincial government while barangay Calamagui 1st and Calamagui 2nd, are
commercial barangays with critical facilities such as hospitals and schools,
Result of simulation study showed that atmagnitude 7.8 earthquake, Calamagui 2nd would have the highest
total damaged floor area and consequently the highest in replacement cost covering 13,180 sq.mareas and
Php 64 million damage cost, respectively. This is attributed to structural types of CWS dominant in this
barangay. At barangayAlibagu on the other hand, the total damaged floor area is 9,789 sq.m. and with
replacement cost of Php 53.4 million. Alibagu is the widest barangay among the three but registered lower
risk than Calamagui due to the dominant structural type of S2 which is stronger than CWS. Calamagui 1st
being the smallest barangay among the three recorded only 3,292 sq.m. damaged floor area and Php 16.3
million replacement cost. Government offices and commercial buildings will be the most damaged
establishments in Alibagu, Calamagui 1st will have major damages on residential areas while Calamagui
2nd would affect mostly schools, hospitals and some residential.
This study showed the capability of the Rapid Earthquake Damage Assessment System (REDAS) program
to give quick estimate of the possible hazards due to earthquake and the severity of the impacts to
population, lifelines, buildings, road networks and other elements-at- risks.

Published

2020-04-30

Issue

Section

Articles