It was on a Monday, April 22, in 1991, when the Limón Earthquake shook the ground with an intensity never before recorded in Costa Rica’s history and never seen again. At 3:57 p.m., with its epicenter in the Valle de la Estrella, 36 kilometers from Limón, a magnitude 7.7 earthquake struck, its impact transcending borders.
According to the National Seismological Network report, the earthquake was felt from Tegucigalpa (Honduras) to Panama City, as well as on the island of San Andrés (Colombia).
The Limón Earthquake also struck Panama
Much of the impact was shared with Panama. While there were 651 injuries on the Costa Rican side, the number of injuries on the Panamanian side rose to 1,061. Regarding deaths, 48 were on the Costa Rican side and 79 in Panama.
In addition, 4,452 collapsed structures and 7,869 damaged homes were reported nationally. The damage inventory from the Limón Earthquake was extensive, impacting 80% of Costa Rica and 20% of Panama.
“The most notable damage and losses occurred to vital lines, including roads, railroads, bridges, ports, and aqueducts,” the RSN summary states. “In Costa Rica, 309 kilometers of roads had to be rebuilt. The total damage (in Costa Rica) amounted to 21,991.9 million colones,” they added.
Limón Earthquake lasting effects
The railway infrastructure was also scarred by the Limón earthquake. The geological imprint is still visible today. In addition to the socioeconomic impact, the Limón Earthquake also generated a geological transformation in the Caribbean, shifting the coastline from Moín in the north to Gandoca in the south.
“The maximum uplift was 1.85 m measured in the vicinity of Limón. Meanwhile, along the coast of Bocas del Toro (in Panama), subsidence of up to 0.9 m occurred,” the Network highlights. This uplift caused the death of all organisms on the coral reefs that remained above water.
“Post-earthquake, a rise in the water table was also identified, ranging between 0.5 and 2.0 m in deltaic areas, especially in Matina and northeast of Limón. Nearly 3,000 km2 were affected by soil liquefaction in the Caribbean coastal lowlands, and an area of 2,000 km2 (much of the Talamanca mountain range) was devastated by landslides,” he adds.
This resulted in the destruction of 50,000 km2 of primary forest. In addition, other seismic events occurred within a few weeks, generating tremors greater than 6.0 in other areas of the country. The summary also included the generation of a tsunami with 2-meter waves that reached the coasts of both Costa Rica and Panama.
The Strongest Earthquakes
As mentioned before, the Limón Earthquake is the largest earthquake ever recorded in the country. According to the National Seismological Network list, the strongest events have been:
Limón, April 22, 1991, 7.7.
Limón, May 7, 1822, 7.6.
Nicoya, September 5, 2012, 7.6.
Golfo Dulce, August 4, 1854, 7.5.
Golfito, April 2, 1983, 7.4.
Central Pacific, December 21, 1939, 7.3.
Osa, December 5, 1941, 7.3.
These events were followed by a 1934 earthquake with an epicenter in Puerto Armuelles, Panama (7.6) and another in Nicaragua in 1992 (7.7), whose effects impacted the country. Finally, other places with earthquakes measuring 7.0 or higher have included Cartago (1948), Papagayo (1916), Orotina (1924), and Grecia (1882).
