Second A-6 viaduct collapse in Spain after two decades

A-6 viaduct collapses again: a two-decade-old structure

The viaduct at kilometer 431 of Spain's A-6 motorway has collapsed for the second time. It is not a relic from the nineteenth century but an infrastructure project from just two decades ago, built to last generations. Official explanations currently point to a "hidden problem" that repair works did not cause. In essence, a structure being reinforced precisely because it showed signs of failure has fallen before reopening.

No one disputes this sequence. What remains debated is responsibility, the role of inspections, and why road network maintenance is often neglected by politicians who prefer new inaugurations.

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Why did the A-6 viaduct collapse?

According to initial statements from the Ministry of Transport, the official version points to an undetected flaw in that section prior to the tendering of reinforcement works. The Minister ruled out the ongoing construction as the cause. A viaduct collapsing while being propped up leaves little room for chance and much for an uncomfortable hypothesis: that structural stability was not verified before intervention.

Technical discussions within the public works sector suggest the collapse could stem from design errors, execution faults, or miscalculated ground settlement. Industry experts note that while calculations are standardized and projects audited, budget stretching during award and execution phases can compromise less visible aspects.

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Warnings from the 1967 highway plan

Before the motorway existed, authorities were aware of the challenges. Studies from the 1967 REDIA plan and 1970s highways concluded that the terrain between Vega de Valcarce and Becerreá was highly unstable for elevated viaducts on the future A-6. Two specific conflict points were named: El Castro and Los Nogales, both in Lugo province.

The viable alternative—expensive for the era—involved lowering the elevation with tunnels, including two approximately four kilometers long. No Spanish company dared assume concession costs, leading to the cancellation of the National Highway Plan in 1977 despite awarded sections. Half a century later, the viaduct fell on the same ground engineers had flagged as risky.

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Maintenance: investment without political returns

This issue is not unique to Spain, which offers some reassurance. Construction Engineering professor Víctor Yepes warns of a global infrastructure crisis if conservation resources are not increased. He cites the United States, where much of the interstate network and bridges date from the 1950s and 60s, suffering decades of deferred maintenance.

Conservation does not generate headlines like ribbon-cutting ceremonies. Repairing Benavente's pavement or reinforcing a viaduct lacks political appeal. The cost of such neglect is paid later, all at once and with interest.

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Why do recent structures fail while older ones endure?

History provides a painful comparison. The Arenales viaduct on the AP-6, built in 1972, was in optimal condition when tested for expansion to three lanes and remained standing fifty years later. The A-6 viaduct did not reach half that lifespan.

Some recall that Spain produced top civil engineers in the past, even when women were rare in the profession. Today, veterans observe the current professional level with nostalgia. While not a decisive argument, it reflects growing discontent.

Suspicion also arises regarding quality reductions in public works, allegedly with the complicity of control bodies. This widespread accusation lacks firm proof. Sector professionals dismiss it practically: flawed calculations are easily attributed to identifiable designers in accidents, making such risks unpopular to sign off on.

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The Italian model and the Genoa warning

The Sarracena Bridge collapse in Genoa serves as another inevitable reference, demonstrating that structures stand until they suddenly don't, and deferred maintenance is unforgiving. Spain's network is younger than Italy's due to later development, which raises concern: if viaducts from the 90s and 2000s are failing, what will remain when the network reaches fifty years?

Resigned observers joke that abandoned infrastructures become greenways for cycling and hiking. This represents a future plan for a country that once aimed for German-quality motorways.

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The prediction is simple yet uncomfortable: if maintenance remains the last budget priority, collapses will cease to be news. With reservations—since a country capable of tunneling through impossible terrain in 1976 is not incapable of preserving existing assets—the scenario points to more collapses and fewer inaugurations. The question is not whether another will occur, but how many pass before someone audits the entire network.