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Earthquake Safety in Trinidad and Tobago – A Call for Action!. Richard Robertson, Lloyd Lynch, Joan Latchman, Walter Salazar, Stacey Edwards, Clevon Ash, Omari Graham, Cassandra La Barrie, Monique Johnson. Summary. - PowerPoint PPT Presentation
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Richard Robertson, Lloyd Lynch, Joan Latchman, Walter Salazar, Stacey Edwards, Clevon Ash, Omari Graham, Cassandra La Barrie, Monique Johnson
Trinidad and Tobago is highly vulnerable to large earthquakes that will occur at close range as well as a major event occurring at a greater distance
Given the present building stock, existing building practises and regulation, the estimated human and economic loss from an extreme event could be significant – as many as 30,000 fatalities and more than US$5 Billion in damage in either of the two largest cities in Trinidad
The best way forward is to implement and sustain a national earthquake risk reduction program aimed at improving earthquake safety to a specific target level
Gather a wide representation of individuals, organisations and stakeholders with involvement in earthquake safety, to thoroughly assess the existing status of earthquake preparedness and to define a way forward to ensue resilience to future damaging earthquakes
Location & geologic setting of Trinidad and Tobago => susceptible to earthquakes
Increased vulnerability and present understanding of regional seismo-tectonics => the earthquake threat is significant
Mitigation requires a comprehensive strategy
SRC and ODPM partnered to host a national consultation entitled “Earhquake Safety in Trinidad and Tobago – A call for action!”
Date: Monday 5-6th July 2010
Participants: > key stakeholders from government, academia, private sector, ngo gatherned for 2 days
Case for Action – the Earthquake Hazard
Case for Action – the Earthquake Risk
Operational Framework – National Disaster Management Institutions
Call for Action – Developing Working Groups & Committees; best practises
Over 120 participants including researcher, practitioner or consumer
Invited speakers to define state of the art with respect to› earthquake hazard and
risk assessment;› issues related to building
profession, planning and regulation;
› activities related disaster preparedness and mitigation
Panel-led discussions after each presentation
National Consultation on Earthquake Safety in Trinidad & TobagoProgramme
Arthur Lok Jack Graduate School of BusinessMt. Hope, Trinidad and Tobago
Day 1 – July 5th, 2010Time Agenda Item Presenter
Case for Action – Earthquake Hazard
Session ChairDr. Richard Robertson
Director – UWI SRC
10:00-10:40
Implications for Trinidad and Tobago of Eastern Caribbean Seismicity Past,
Present and Future
Dr. Joan LatchmanSeismologist - UWI SRC
10:40 -11:20Trinidad and Tobago in the Current
Hazard Picture for the Eastern Caribbean.
Dr. Walter SalazarEarthquake Engineer -
UWI SRC
11:20 -12:00A Case for a National Earthquake Risk
Reduction Programme
Mr. Lloyd LynchInstrumentation Eng. -
UWI SRC12:00 - 12:30 Q&A Discussion All12:30 - 02:00 L U N C H
Case for Action – Earthquake Risk
Session ChairMs Desiree JosephMitigation Officer -
ODPM
2:00-2:40Perspectives on Earthquake Risk
Assessment & Management
Prof. Jacob OpadeyiHead of Dept. UWI
DSLI
2:40 – 3:20Seismic Risk and Civil Infrastructure in
Trinidad and Tobago
Dr. Richard ClarkeSenior Lecturer – UWI
DCEE3:20 – 3:35 B R E A K
3:35-3:55Remarks on Vulnerability of Trinidad &
Tobago Infrastructure
Mr. Marlon FeveckSenior Civil EngineerMinistry of Works and
Transport3:35 – 4:25 Q&A Discussion All
4:25 – 4:30 Close
Session Chair,Ms Desiree JosephMitigation Officer -
ODPM
There is mounting seismotectonic evidence that one or more earthquakes of extremely destructive potential is looming on the horizon in the SE Caribbean
Located Earthquakes 1955 – 2010/05
• North Paria Peninsula (deeper earthquakes (50-200 km) - the most significant earthquake source
• Gulf of Paria (shallow earthquakes)
• Southwest of Tobago (shallow earthquakes)
• Southeast of Trinidad (30-100 km)
Using GPS measurements Weber et al has shown that 65% (~13mm/yr) of present day motion between the Ca-SA plate boundaries in the SE Caribbean is accommodated on the Central Range/Warm Springs Fault
Zone 11• North of Paria Peninsula: log N = 3.643 – 0.783 M
Recurrence interval* (T=1/N):M=7.7: 243 years + 1766 = 2009 last big earthquake
M = 8.3 : 718 years
Size of the earthquakes
*Recurrence interval: refers to the average time between earthquakes of a particular magnitude or larger in a given seismic source
The ground motions produced by these earthquakes are likely to exceed those experienced during most earthquakes that have affected Trinidad and Tobago in the last 200 years and will rigorously test the stress threshold of the built environment
Strong ground shaking from such an earthquake can continue for more than two minutes during which time it is unsafe to move around within buildings.
Damage From Ground Shaking
Antigua – Elephant foot buckling spillage into bund
1974/10/08 Mag.7.4.
Antigua – Compaction at Port 1974/10/08 Mag.7.4.
HAZARD MAP 2475 YEARS RETURN PERIODPEAK GROUND ACCELERATION
Port of Spain
San Fernando
Point Fortin
HAZARD MAP 475 YEARS RETURN PERIODPEAK GROUND ACCELERATION
Port of Spain
San Fernando
Point Fortin
Rock conditions Rock conditions
(0.33g)
(0.28g)
(0.26g)
(0.58g)
(0.52g)
(0.48g)
~ 70% of commercial structures inspected by the Design Engineering Branch of the Ministry of Works and Transport for approval have not met suitable code requirements for earthquake resistance.
Commercial and industrial zones on the west coast will experience anomalously high ground shaking during strong earthquakes. This increases the possibility of exposure to secondary hazards such as fire, liquefaction, ground settlement and subsidence surge.
Current risk transfer portfolio in Trinidad and Tobago is grossly inadequate to cover losses from a large earthquake:› less than 25% of properties are insured;› CCRIF contributions will provide governments with short-
term liquidity not recovery
The national disaster management agency was only recently (2005) restructured and given the mandate and resources to manage disaster using contemporary approaches
The population at large is oblivious to the prevailing state of affairs
Implement and sustain a national earthquake risk reduction program aimed at improving earthquake safety to a specific target level
Establish a National Earthquake Stakeholder Organizatoin (NESO) with a Steering Committee to take the work forward
The NESO should be a public-private partnership to which any individual or organisation desirous of working toward Earthquake Risk Reduction should be invited to participate.
Arrange a meeting with the Government comprising of key ministers to brief them of the outcome of the meeting and the recommendations made with respect to Earthquake Risk Reduction
Organise a series of workshops/meetings to discuss and undertake the following:› Establish work groups and define a work programme› Establish a Steering Committee for the NESO› Designate an operational base› Develop a business plan for the organisation
Trinidad and Tobago is highly vulnerable to large earthquakes that will occur at close range as well as a major event occurring at a greater distance
Given the present building stock, existing building practises and regulation, the estimated human and economic loss from an extreme event could be significant – as many as 30,000 fatalities and more than US$5 Billion in damage in either of the two largest cities in Trinidad
The best way forward is to implement and sustain a national earthquake risk reduction program aimed at improving earthquake safety to a specific target level
Seismic Research CentreUniversity of the West IndiesGordon StreetSt. AugustineTrinidad and Tobago
Tel: +1 868 662 4659Fax: +1 868 663 9293Email: uwiseismic @ uwiseismic . comWeb: www . uwiseismic . com