Whole Lotta Shakin’ Going On: Nicaragua Rattled By Multiple EarthquakesJune 26, 2014
Nicaragua remains on “red alert” following a cluster of pre-Easter earthquakes that killed two people; damaged nearly 5,000 homes, some completely; opened up a 20 km-long crack in the earth; and may have even caused an odd drop in the water level of Lago Xolotlán, also known as Lake Managua.
The first of the quakes, measuring 6.2 on the Richter scale, struck on the evening of April 10. Hardest hit was the town of Nagarote, located some 50 kms northwest of Managua, the Nicaraguan capital, where damage was also reported. The quake leveled approximately 300 Nagarote dwellings and left another 600 inhabitable, El Nuevo Diario reported.
That night President Daniel Ortega issued an official “alerta roja.” The red alert has since been upgraded to an “alerta roja extrema,” which remains in effect for much of the area around Lago Xolotlán. “We share the pain of the families that have been affected,” he said. “We have to be prepared, because these are signs from nature, signs from God, telling us to protect ourselves, to act responsibly. This isn’t about sowing fear, or sowing terror. But it is a call for responsibility, so that we can protect our families.”
The president’s message proved to be apropros. Less than 24 hours later, Nicaragua was hit by a second, even stronger quake (6.6-magnitude). The follow-up tremor caused relatively minimal damage but raised widespread concern that together the two jolts might be signaling an even greater disaster to come.
“There have been tremors during the night, very strong ones. And during the day it shakes ever hour, every hour-and-a-half,” a Managua resident named Lucila Delgado told BBC Mundo. You feel super tense, always on alert, listening to the radio all day, not knowing what can happen, thinking [the house] can crash down on you at any moment.”
“The situation is strange”
First lady and government spokesperson Rosario Murillo did little to dispel those concerns when, in an April 13 televised address, she suggested that the earthquakes may have “activated the faults beneath Managua.”
By far Nicaragua’s largest city, Managua has a population of more than 1 million. It also has a history of seriously destructive earthquakes that, over the past century-and-a-half, have occurred at intervals of roughly 40-45 years. The last major quake struck the city in 1972 (42 years ago), killings thousands and leveling all but a handful of the Managua’s major buildings. The Nicaraguan capital was also devastated by quakes in 1885 and 1931.
Murillo, who heads the government’s Consejo de Comunicación y Ciudadanía del Poder Ciudadano, warned people to sleep outside or with their doors open. “We’re full of lakes, lagoons, volcanoes and threatened by faults. It’s part of our life that we have to recognize as a reality and prepare ourselves,” she said.
Adding to the drama were comments by German-born geophysicist Wilfred Straus of the Instituto Nicaragüense de Estudios Territoriales (INETER). “To tell the truth, we’re a little worried about the possibility [of a major quake in Managua],” he told reporters. “We see that something is changing, that something is getting closer to Managua. We can’t predict anything, but the situation is strange. It’s not normal.”
Nerve-rattling tremors have continued to shake the area. A 5.1-magnitude jolt struck on the night of April 13. Authorities registered another sizeable shake (4.6) on the morning of April 15. Similar magnitude events occurred on April 18 (4.3), April 19 (4.4), April 21 (4.3), April 23 (4.4, April 26 (4.3) and May 1 (4.7).
Thankfully, though, the dreaded “big one” has not materialized. And as the frequency and force of the tremors has gradually tailed off, life in and around the quake zone has slowly regained some semblance of normalcy. Researchers from the Universidad Nacional Autónoma de Nicaragua (UNAN) now say that the original April 10-11 earthquakes did not, as had been feared, activate Managua’s dangerous fault lines. Nicaragua, it would seem, dodged a bullet.
The Ortega administration continues, nevertheless, to keep the country on alert. In the meantime, it has launched reconstruction efforts in Nagarote and other areas hit hard by the quakes and, as a preventative measure, ordered the demolition in Managua of several buildings that survived the 1972 disaster but are now deemed unsafe.
Managua was also the scene on April 27 of an elaborate earthquake drill organized by the Sistema Nacional para la Prevención, Mitigación y Atención de Desastres, or SINAPRED. The drill took place at the Mercado Oriental, Nicaragua’s largest market place, and involved thousands of participants. Authorities have organized mock evacuations in other market places as well.
“What we’re doing here is building a protective consciousness, a permanent vigilance. Above all – through these climatic, volcanic and seismic episodes – we’re strengthening bonds of affection between Nicaraguan families and communities,” Rosario Murillo told reporters April 19.
Ticking time bomb?
And yet for all of the government’s efforts to demolish, conduct earthquake drills and be “permanently vigilant,” it remains unclear how Nicaragua will fare should a major quake strike the capital directly.
The city is crisscrossed with fault lines, including the Tiscapa and Estadio faults that were responsible of the 1931 and 1972 earthquakes respectively. Scientists from UNAN’s Instituto de Geología y Geodesia (IGG) recently concluded a study focused on six of those fault lines. But there are many others about which little to nothing is known, according to the IGG’s director, Dionisio Rodríguez. “They say that in Managua there are 16 [fault lines]. Others say there are 18. Those need to be studied systematically,” Rodríguez explained during a recent presentation. Nicaragua’s current seismic maps are “out of date and contain incorrect information,” he added.
The city’s many fault lines are only part of the problem. Another factor is Managua’s volcanic subsoil, which is relatively new, extremely loose and thus particularly volatile when shaken, seismologists warn. Seismic events that would be considered manageable elsewhere, such as the 6.2-magnitude quake of 1972, can cause nightmarish devastation in Managua.
Building materials and overall construction quality also play a role in how well cities fare during earthquakes. Despite the lessons learned from past experiences, Nicaragua – one of the hemisphere’s most impoverished countries – continues to be vulnerable in this regard. The April 10 quake in Nagarote was a case in point: the hundreds of homes that collapsed were simply not built to withstand the kinds of seismic shifts that can so easily occur in Nicaragua.
“I started building my house with plastic, then with corrugated metal, until it was finally standing,” Blanca Estela Medrano Pérez, a 52-year-old Nagarote resident whose home collapsed, told the Sandinista news site El 19. “The earthquake did away with 25 years of sacrifice. It took 25 years to build this house, and now I see this,” she said, pointing to the ruins.
(This article originally appeared May 8, 2014 in LADB)