Oaxaca tower that collapsed in a storm. Oaxaca tower that collapsed in a storm.

Oaxaca blamed for seismic system faults

Malfunctioning sensors mean Mexico City can't receive quake warnings

There is no good time for an earthquake but if a large one strikes now with an epicenter in Oaxaca, the consequences could potentially be even more catastrophic.

The southern state’s seismic alert system is not sending signals to Mexico City, the capital’s mayor said yesterday, meaning that if a temblor occurs there, alarms in the megalopolis won’t be automatically activated.

“We’re corroborating . . . [to see] if there is a defect in the transmission or [find out] what is happening, but it’s my duty to inform citizens that we’ve received a report that there is no service in the Oaxaca seismic alert stations. All the rest are working, but at the moment, the ones in Oaxaca are not,” Mayor Miguel Ángel Mangera said.

When an earthquake occurs in Oaxaca, an alert transmitted by loudspeakers in Mexico City can give residents up to 50 seconds to evacuate buildings before the temblor is felt.

It activated when the first of last September’s large earthquakes struck in the Gulf of Tehuantepec, although no serious damage was recorded in Mexico City.

The system’s efficacy was nullified in the second of September’s large quakes because of the close proximity of its epicenter.

Following Mancera’s announcement, the director of the Center for Seismic Instrumentation and Registry (Cires)— a non-government organization responsible for administering the alert system — said that 14 of the 37 seismic sensors in Oaxaca were out of action due to wind damage.

One tower, located in San Antonio Cuajimoloyas in the north of the state, collapsed completely in recent storms.

Juan Manuel Espinosa explained that no money had been allocated for their repair and that the organization didn’t have a contract with the Oaxaca state government.

He added that that government has accumulated a 24-million-peso (US $1.3-million) debt with Cires since 2012 and a further 14 million pesos will be needed for repair and maintenance work this year.

Oaxaca Governor Alejandro Murat accepted that the government owed the money but claimed that it was a debt that he inherited from his predecessor, Gabino Cué.

He also said that the federal government is acting as a mediator in talks with Cires to establish payments that are fair and equitable, considering that Mexico City and states in central Mexico benefit more from the alert system than Oaxaca.

Once the money is forthcoming, the repair work on damaged towers and sensors will take around 15 days, Espinosa said.

In another press conference today, Mancera said he had spoken to the governor of Oaxaca and that Murat assured him repair work had started.

He said that Murat told him that the collapsed tower, which affected 40% of the sensors that transmit to the capital, would be operational again in the coming days.

The mayor also sought to allay fears about the consequences of the alarm being out of action, explaining that sensors in Puebla and other states near the capital would alert Mexico City residents of the impending arrival of seismic activity, albeit with less time to react.

“. . . Of course, we would have a shorter period of time [to evacuate], that’s the consequence,” Mancera said.

Source: El Universal (sp), Milenio (sp)

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