TT on cusp of big earthquake

“It requires Government and us as a people to make decisions quickly, and to act quickly,” seismologist at the University of the West Indies Seismic Research Centre (SRC), Dr Richard Robertson, has said.

Robertson made the comment at a recent workshop, titled “Lessons Drawn from the Seismological Experience in Chile and its Application to Trinidad and Tobago”, at City Hall, Port-of-Spain.

“We have been monitoring seismic hazards for some time and we are exposed to the hazards, and can be impacted by a large magnitude earthquake. As professionals in the field, we don’t think as country or a region we have gotten it right,” he said.

“There are initiatives from people like Caribbean Disaster Emergency Management Agency (CDEMA), CARICOM Regional Organisation for Standards and Quality (CROSQ), CARICOM, and people doing things locally, but we think they are moving too slow.”Research Fellow in Earthquake Engineering at the SRC, Dr Walter Salazar, said the Government, through the Town and Country Planning Division and SRC, had attempted to put things in place by initiating a Microzonation Database Programme.

The database, which will detail seismic hazard risk for all areas of the country, is being funded by Government and will cover a ten-year period.

In an address on the occasion of World Town Planning Day on November 8, Planning Minister Bhoe Tewarie said, “It is hoped this project will guide the establishment of new building codes and modify site development standards that will take into consideration the potential and very real risks our present and future structures face from seismic activity.”

It is necessary, he said, “for all new attempts at land use planning to be informed by hazardous assessments so that mitigation planning can be filtered into design and land use policy conceptualisation.”

The issue of proper land planning and usage was reinforced by last weekend’s severe flooding in north-west Trinidad, which many attributed to the ill-advised removal of vegetation on hillsides by developers for housing.

Addressing the issue earthquakes, Robertson said, “To get to the stage where we are resilient to seismic hazard, it will take years. We need to start, but we are taking too long to start. An earthquake may occur before anything could be done.” From interaction with engineers, he said, “we are concerned about the buildings environment and the extent to which they can withstand the kinds of events we would expect. We have lots of problems. How the buildings are built, problems with respect to regulations and codes.”

Most Caribbean islands, he said, have building codes that may not be up to date, but are regulated in terms of enforcement mechanisms.

In addition to seismologist and engineers, he said more persons from other fields need to get involved in preparation for seismic hazards

The earthquake of January 12, 2010, in Haiti, he said, “should have, as a region, made us aware of the problems.”

How Chile manages seismic hazards, he said, “should have indicated to us what we should move from and what we should move to in terms of our building stock.”

Professor of Structural Engineering at the University of the Andes, Jorge Crempien, in addressing the earthquake problem in Chile, said Chilean seismic regulations started with the Chilean Ordinance for Construction (ChOC) in 1928 after the Talca earthquake. It addressed only construction issues. It was updated in 1939 after the Chillan earthquake that year. Following the 1960 “Great Earthquake”, the ChOC was complemented by the Seismic Design Code for buildings, which incorporated “the mandatory dynamic analysis of buildings”.

The seismic design code, he said, restricted the design of buildings only to structural engineers for buildings of more than three stories.

The seismic design code, he said, had “tremendous success” in the 7.8 magnitude earthquake of 1985 in the central zone of Chile. After this earthquake, the code was updated to include seismic macro zones. The seismic data obtained from the seismic macro zones helped to define the code in use during the 2010 earthquake.

“It worked very well,” Crempien said.

Acting Director of the UWI Seismic Research Centre, Dr Joan Latchman, said, “Our engineers are expressing concern about the stock of our buildings, even those that are engineered.”

The engineers in TT and the region, she noted, could learn from the Chilean experience.

TT also needs to legislate on building codes, Latchman said, noting that a building code committee is currently looking to get a code that can be used here.

Along with the code, she said, “there must be enforcement mechanisms in place to ensure monitoring at all stages of the building process to ensure that buildings meet code requirements.”

“What we put in place now should stand. The resources that we are using to put these things in place are not renewable resources. When we spend that money foolishly investing in something that is going to fall down the next time we have a major earthquake, we must ask ourselves ‘Where are the resources coming from?’”

Research Fellow in Earthquake Engineering at the SRC, Dr Walter Salazar, said the priority for TT is to conduct risk assessment in critical facilities and public buildings, such as hospitals and schools, that have high levels of occupancy, and economic installations.

Research Fellow in Instrumentation at the SRC, Lloyd Lynch, said, “The truth is that no assessment has been done to determine how safe public buildings are.”

Indicators such as building codes in keeping with international standards, building standards and practices, and monitoring and inspection of the construction process, would determine the safety of buildings, Lynch said.

Engineers at the seminar expressed concern that these indicators were either absent or inferior to international standards.

Even before a building goes up, Lynch said, strong local government institutions, such as Town and Country Planning, should ensure that a location or site is suitable to build on.

“Unfortunately, our institutions have not been effective in putting measures in place. Even buildings that are engineered have deficiencies because of the lack of quality assurance and monitoring.”

Giving the reason for the absence of an up-to-date building code, Lynch said that engineering professionals in the 1970s recognised that benefits were to be obtained from the use of the code.

“At that time, attempts were made to put together a Caribbean unified building code. It was 75 per cent complete in the late 1980s. By the time it was completed the world had moved on. In the early 1990s, the three organisations governing building codes in the US formed an International Building Code Council and introduced ‘The International Building Code’, which was radically different from the previous codes. This rendered the Caribbean effort at obtaining a regional code obsolete.”

On pre-financing for disasters, Lynch said that Government subscribes to the Caribbean Catastrophic Risk Insurance Facility (CRIFT), which was set up to provide quick funds to take care of contingency expenses in a disaster until more permanent arrangements could be made.

Apart from CRIFT, he said, “We have private insurance but the amount of private insurance for disasters in the Caribbean is rather low.“Less than 15 per cent of infrastructure is insured. Even those that are insured, are under-insured.”

Insurance regulations, he said, “are so archaic we risk the possibility that in the event of a large earthquake or any major catastrophe, some of these insurance firms will go insolvent.”

Another problem, he said, is that many companies do not submit financial statements on a timely basis, so things can go awry without being detected.

Governments need to put aside more funding to deal with major disasters that will inflict huge financial losses, because they will be faced with huge contingent liability.

“We need to look at things such as a residential catastrophe pool, or a business contingency pool or insurances for businesses. It will need radical changes in terms of incentives that government gives to financial entities such as insurances companies,” he said.

“We need to accept the fact that before all these measures are put in place, we could get a large earthquake and as such, we need to have measures in place to pre-finance the disaster so that businesses can recover quickly.”

Given all that is at stake, Lynch said that if Government was serious about sustainable development, and meeting the Millennium Development Goal “it would be necessary to spend more on preparedness for earthquakes”.

Since the country had gained political independence, he said the economy had grown four times. However, this growth has gone in areas of human development and standard of living, noting citizens benefit from Government’s Chronic Disease Assistance Programme; students benefit from Government Assistance for Tuition Expenses and the population benefit from gas subsidies.

A large earthquake, or a shallow moderate one occurring under San Fernando or Port-of-Spain, he said, “can easily inflict damage that is so large that a lot of these subsidies will have to be taken away. The budget would have to be adjusted so as to make amends for the damage inflicted, and all of those development gains will go out the door.”

Questioning the amount of capital invested in the accumulation of buildings and infrastructure, including bridges and overpasses, he said, “In an earthquake, a lot of that could be shaken to rubbles in seconds. It is very important we pay more attention to this. It is inevitable.”

Earthquakes in developing countries, he said, tend to be quite costly in terms of the amount of repairs that need to be done to infrastructure afterwards, business opportunities lost and the impact on human societies based on lives lost.

Some of the preliminary estimates that have been done, he said, indicate that an earthquake could wreak damage in the tune of US$6 billion in San Fernando alone. Residential housing stock alone in Port-of-Spain could be in the sum of TT$10 million.

“We have to work hastily to start putting measures in place to start transforming the building stock and to put emergency measures in place to respond to the inevitable,” he said.

The level of shaking of the earthquake and the depth determines the extent of damage, the experts said. Dr Latchman said a shallow 5.8 magnitude earthquake destroyed Managua in 1972 because it occurred at a depth of seven kilometres right under the Nicaraguan city.

“We have a shallow earthquake in the magnitude range of 6.1 to 6.5 on the Richter scale occurring every ten or so years somewhere around Trinidad that could destroy a city within seconds,” she said.

“All of these earthquakes, had they occurred under Port-of-Spain, would have been completely devastating.

“It is just that they have been slapping at our heels, occurring off the island. It just takes one such earthquake to occur under Port-of-Spain or San Fernando and it would be a completely different story.”

In San Fernando, Lynch said, the SRC has uncovered in recent times geologic structures in the Central Range Fault that “may be accumulating strain and could rupture sometime in the future”. He said these geological structures cut right through some of the most productive regions of the island, including Point Lisas, San Fernando’s residential areas and Point-a-Pierre.

In the event of a large earthquake, these communities will suffer strong shaking and are likely to experience huge amount of damage.

As nationals, Lachman said, “we need to take some personal responsibility for our own safety, given that we would be living in structures that may not live up to a massive earthquake. So we need to have our disaster bag, medical kit batteries, torch- lights and have them stocked. Have family plan at every time. Earthquake has no respect for season. They can occur at any time of the year.”