Mexico City subway collapse was a tragedy foretold
MEXICO CITY — The Mexico City elevated subway line that collapsed this week, killing 25 people, was problem-plagued and poorly designed from the day of its inauguration in 2012.
Passengers and authorities alike came to fear that the screeching and bouncing of wheels on the line's tight curves were quickly wearing away the tracks, raising fears of a derailment.
But few expected the thing would simply collapse.
However, an official 2017 survey of damage caused by a deadly 7.1 magnitude quake showed indications of construction defects that should have shut the line down immediately, according to an experienced structural engineer.
José Antonio López Meza said the defects detected in the subway system report — a sagging section of too-weak steel near the latest accident — is the kind of thing that could have contributed to Monday's collapse.
Instead, authorities decided on quick patches, welding props under the bowed beams and reopening service.
“Here in Mexico, nothing is taken care of until a tragedy occurs,” said López Meza, a seismic and structural engineering consultant.
But authorities weren't concentrating on structural defects. They had their hands full over the last decade simply trying to keep the subway train on its tracks, to avoid what could arguably have been have an even more nightmarish failure than Monday's collapse involving two subway cars.
The $1.3 billion Number 12 Line, the newest section of a vast subway system opened in 1969, was ill-fated from the start. The so-called Gold Line cost half again as much as projected, suffered repeated construction delays and was hit with allegations of design flaws, corruption and conflicts of interest.
