Ecuador: behind the disaster
Last April 16th at 18:58 local time, a seismic event of 7,8 degrees shook the Ecuadorean region of Manabí, being the strongest seism in the country since 1987. It was such a powerful earthquake, that the seismic waves were felt abroad the nation, reaching as far as the cities of Cali & Pasto in Colombia or Tumbes & Piura in Peru. The number of victims and injured people are devastating: recent figures indicate 659 fatalities, 27.732 injured and 40 missing people. Assuming that the earthquake was severe, one cannot ignore the fact that behind these figures transcends a thought: What is failing in a country that was meant to have all the anti-seismic preventions to have such fatality figures?
If there is any legal framework able to guarantee the security of citizens in a country like Ecuador, that is the NEC-SD-DS, the Ecuatorian Standards for Seismic Resistant Design and Construction. Within the standards, there is a complete breakdown of appendices to regulate the way different structural typologies need to be designed and dimensioned: reinforced concrete, wood and steel structures among others. A large part of these standards are based on American ASTM Standards, which is always a guarantee.
Besides structural typology, another relevant factor is the seismic area where the construction is going to be implemented. Overall within the regulation there a 6 different seismic zones, being the epicentre of the earthquake right in the most risky area, between the regions of Pedernales and Cojimíes. Logically, the higher the risk level is, the higher applicable requirements to the structural components.
As the third factor, after the structural typology and the seismic zone, the NEC-SD-DS within its definitions specifies the different security levels to be guaranteed. The most relevant one, defined like “Life Security Level” or “Seismic Design” seeks to protect the life of the tenants against an earthquake with a return period of 475 years, that therefore, has a annual chance of 0.002% to occur, in other words, a 10% of probabilities to happen in 50 years. Taking into account the consequences of the earthquake of 1987 with over 1.000 fatalities and the current ones with over 650, after only 29 years, it is clear that something does not work. But the problem is not the regulation.
So, if there is nothing wrong with the NEC, what is failing? The answer we found is related to the deficient self-construction and the non-compliance of the regulations. In accordance with the data from the Latinamerican Bank for Development, in 2012, 50% of Ecuatorian families have no roof over their heads, or they live in unworthy conditions. This reality combined with a 7,8 degree earthquake becomes a perfect storm for low socio-economic social strata.
The comparisons are odious, but turning around our eyes to the south we will see how Chili, under similar conditions & regulations, is able to face these natural disasters. Measuring 8.8 on the Richter Scale, a point higher than in Ecuador and being the 8th most aggressive earthquake in the history of humankind, the seismic movement of 2010 in Chili caused 525. The difference might not look to wide, but it must be understood that a considerable part of the deaths were caused by a tsunami that razed the coastal cities, and not by the massive collapse of the buildings.
Back to the references of the Latinamerican Bank of Development, we will see that the gap between the families living in poor conditions in Ecuador and Chili, is a 27%, less than the half. This seems to confirm the obvious theory that there is a direct link between the poor living conditions of the families and the earthquake mortality rates. In any case, what we can be sure of is that the cause of so many deaths is much more linked to the precariousness that to the existing regulations.
Against this background, from our point of view, Ecuadorian institutions should focus their efforts in two main directions: the first one, to invest additional efforts in order to carry out a proper control over the NEC, ensuring that when a new earthquake occurs, buildings will endure. The second one, much more complex to be developed, is to create the conditions to enable the access of the families to worthy and safe social housing. Like in many other areas, pre-engineered housing solutions will play a relevant role in this new stage that needs to start immediately.