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ODPEM officer says massive quake could destroy sections of Kingston

Published:Monday | July 22, 2013 | 12:00 AM

Daviot Kelly, Staff Reporter

SECTIONS OF Kingston and St Andrew, including those housing critical facilities, could take a massive hit if Jamaica was rocked by an earthquake equal to the 2010 tremor in Haiti.

Major Marlon Brown, eastern regional coordinator at the Office of Disaster Preparedness and Emergency Management (ODPEM), revealed the agency did a rapid visual screening (RVS) of hospitals, fire stations and police stations in 2012.

"And based on the criteria used, if we should get an earthquake of the magnitude that Haiti did, we would really be left with only one facility still standing," he said, pointing to the Stony Hill Fire Station.

"This has now drawn into focus how it is that we go about planning and development as a city and a country."

Brown said ODPEM was working with the Earthquake Unit at the University of the West Indies, Mona, and other agencies "to either retrofit those existing buildings that we have or to abandon them altogether and find more suitable locations." Brown noted Jamaica has more than 280 tremors annually.

While the RVS was only for critical facilities, Brown said there were plans to screen other buildings.

"We are working with the Earthquake Unit to do some mappings first and then complete all of the profiles," he said. Brown noted a major component of the study involved soil type.

"They (soils) are graded from A to D, where D is the worst of it, which is what we call the alluvial soil type," he said. "Once you have a shaking, if you're on one of those soil types, you're going to feel the shake a lot more." Brown said this allows for liquefaction, a phenomenon in which the strength and stiffness of a soil is reduced by earthquake shaking or other rapid loading. This is what destroyed Port Royal.

WORST-CASE SCENARIO

"Based on the studies that have been done on the Kingston region, we are on alluvial soil type for the most part," he said, noting other buildings might also suffer heavy damage. But he assured that ODPEM was not predicting widespread devastation, as the model used was merely to give an indication of the possible scale of destruction that may occur with an earthquake of such magnitude.

"We normally plan for worse-case scenarios, so that you're planning for everything," he said. Brown said there were other variables to consider, including how the particular building was constructed and how modern it is.

"Some areas may be deeper than others, which means that you may meet up on harder rocks, bed rocks quicker than in some areas," he explained. "So buildings located in those areas will remain standing more or less not having any problems."

A magnitude 7.0 earthquake rocked Haiti in 2010, killing an estimated 220,000 people and causing either damage or destruction to some 250,000 residences and 30,000 commercial buildings.