©️Benoît Aquin
Pétion-Ville, September 2, 2025.- Wherever there is a seismic source, there is a risk of an earthquake, warns immediately the engineer-geologist Claude Preptit. Located on a major geological fault, Haiti remains particularly exposed to recurrent and potentially destructive earthquakes. The scientific data, as well as the lessons of history, underline the urgent need to act: without prevention policy or strong state authority, the seismic threat will continue to undermine any development ambition.
The earthquake is a natural phenomenon, but its dramatic consequences are not only fatal. As the engineer-geologist Claude Preptit points out, « disasters largely result from serious errors in construction and spatial planning ». Located at the junction of the Caribbean and North America plates, Haiti is part of a seismically active area, exposed to permanent risks.
Therefore, understanding this threat, analysing structural and social vulnerabilities, and defining prevention strategies are essential for any sustainable development project worthy of this name.
The faults and mechanics of earthquakes
« Haiti is crossed by two major active flaws », explains the engineer-geologist Claude Preptit. The first, the fault of the southern peninsula (the so-called fault of Enriquillo-Plantain Garden) extends from Tiburon to Enriquillo and led to the devastating earthquake of 12 January 2010. The second, the northern fault, runs along the north coast to the Dominican Republic.
These two faults accumulate elastic stresses measured by GPS each year: 6 mm/year for the first, 12 mm/year for the second (Calais, Manaker et al. 2008). When a rupture occurs, the accumulated energy is released abruptly in the form of seismic waves (P waves, S waves and surface waves) as highlighted in Geominergie Bulletin No. 9 (BME, 2023). « It is this mechanism that causes the vibrations felt on the surface », recalls Preptit. These shocks can be amplified according to the nature of the soil, causing phenomena such as liquefaction or landslides.
Seismic risk: threat and vulnerability
In risk management, an earthquake is considered a natural hazard that becomes a risk only when it threatens vulnerable populations or infrastructure. « The problem in Haiti is the fragility of our buildings », deplores the engineer-geologist Claude Preptit. The massive damage caused by the earthquake of 12 January 2010, 105,000 homes destroyed and more than 208,000 damaged, according to the Post Disaster Needs Assessment Report (PDNA, 2010) — This structural vulnerability is perfectly illustrated.
The Bureau of Mines and Energy (BME) defines seismic risk as the combination of the hazard (i.e. the probability that an earthquake will occur at a given location within a specified period of time) and the vulnerability, i.e. the severity of the potential consequences on populations and infrastructure (BME, Geomitnergie No. 9, 2023).
A recurring seismic history
Haiti's history shows that earthquakes are both cyclical and recurrent. In 1751 Port-au-Prince was completely destroyed. Less than twenty years later, in 1770, another earthquake violently struck the capital as well as Cap-Haitien. On May 8, 1842, an earthquake of an estimated magnitude of 8 devastated the north of the country and triggered a deadly tsunami.
After a long period of decline, the earthquake of 12 January 2010 left more than 200,000 dead and 1.5 million homeless. More recently, on 14 August 2021, an earthquake of magnitude 7.2 struck the southern peninsula, causing more than 2,200 deaths and nearly 54,000 houses destroyed. This historical memory reminds us that the seismic risk in Haiti is not hypothetical: it is real, permanent and inevitable.
Areas most at risk
« The southern and northern regions are the most threatened », insists the engineer-geologist Claude Preptit. The South peninsula, which was the scene of the 2021 earthquake, has a particularly high seismic potential. The Great North, for its part, remains extremely vulnerable: according to the North Earthquake Plan published in 2016, an earthquake of magnitude 8 could cause more than 10% loss of life in densely populated cities such as Cap-Haitien, Fort-Liberté or Ouanaminthe.
These alarming projections recall the urgency of strengthening prevention and resilience policies in risk areas.
The centre of the country appears relatively less exposed, but the geologist grade:
« Even secondary faults, such as Léogâne's in 2010, can surprise. »
Parasmic construction: a national imperative
Earthquakes are inevitable, but disasters are not. The 2010 earthquake showed that human and material losses were due as much to the power of the earthquake as to the fragility of buildings.
Parasimistic norms must therefore be at the heart of any policy of reconstruction and spatial planning. This implies:
– Design buildings capable of resisting vertical waves, shearing and twisting;
– Choosing safe sites away from fault zones and unstable soils;
– To put in place strict sanctions against professionals who do not comply with the standards in force.
For Claude Preptit, « We need to invest so that homes can withstand an earthquake of magnitude greater than 7 ». This implies a shared responsibility between the State and citizens.
The State has a central role to play:
– Define a suitable construction code;
– To impose strict respect for them;
– Sanction failed engineers and builders;
– Develop safe social housing programmes for the most vulnerable.
Citizens, for their part, must involve:
– Consult with qualified professionals;
– Refuse improvised or unregulated constructions.
*Prevention, education and risk management*
Seismic risk management is carried out in three phases (BME, Geominergie n°9, 2023):
Before:
– Awareness and preventive information;
– Seismic microzoning;
– Fault monitoring and mapping;
– Evacuation exercises.
During:
– Alarm trigger;
– Rescue and first aid;
– Establishment of emergency shelters.
After:
– Rapid damage assessment;
– Support for disaster victims;
– Resilient reconstruction, incorporating lessons from the past
Since 2010, Haiti has had a network of seismic stations, newsletters and microzoning initiatives for Port-au-Prince and the Great North. But the resources are still insufficient. For Preptit, education is a priority: « even at school level, it is necessary to integrate knowledge of seismic risks so that children develop the right reflexes».
Natural hazards and sustainable development
Beyond the seismic risk, Haiti is exposed to seven major threats: cyclones, floods, landslides, earthquakes, tsunamis, drought and climate change. These recurring dangers directly undermine any ambition for sustainable development.
As Claude Preptit points out, « Every step towards development, a disaster can destroy everything and force it to start again ». Thus, reducing vulnerability to these natural risks is not only a necessity, but a sine qua non for ensuring sustainable economic and social progress in Haiti.
In conclusion, Claude Preptit's message is unequivocal: « The earthquakes are not preventable, but their consequences are. » Strengthening building standards, rigorous enforcement of sanctions, continuous risk education and institution-building must become national priorities. For, as he recalls, « If we don't manage our risks, they're the ones who will eventually manage us. ».
R.J.
