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A less than watertight project

The construction of the second-longest tunnel in Spain has been plagued by leaks

Ramming two 25-kilometer long tubes through the Picos de Europa has been a fiasco

A construction site outside the Pajares rail tunnel.
A construction site outside the Pajares rail tunnel.

In northern León, along the border with Asturias, the rivers no longer run like they used to. And they never will again.

"Look at that brook. You can see the mark where the water used to reach a few years ago. Now it's 40 centimeters lower, despite the fact that it's been raining nonstop. It never dried up before, yet now it's running dry," says Fernando Castañón, a 57-year-old cattleman with long white sideburns who drives a small all-terrain vehicle at breakneck speed while complaining that the loss of water affects his herd of 60 cattle head. Several hundred meters beneath his feet, the Pajares tunnels — the most complex, expensive stretch of the high-speed AVE rail system — have rerouted the water to Asturias. Construction work has run into 20 aquifers, raising the cost to 3.2 billion euros, three times over the initial budget. Or in other words, over 60 million euros per kilometer of tunnel. "Damned engineers," grumbles the cattle raiser.

The engineers that Castañón blames for his problems are those in the employment of Adif, the government agency building the new link between Asturias and the plateau. This high-speed line should put the old mountain railroad tracks, built in 1884, out of service. But so far, the feat of ramming two 25-kilometer long tubes through the Picos de Europa has been a fiasco. The seventh-longest train tunnel in the world and second-longest in Spain is bogged down by leaks and banks that keep caving in. The tunnels have been dug since 2009, but no opening date has been announced yet.

The Pajares tunnels have rerouted the water from León to Asturias

The project is a mirror of the last decade in Spain. Its ups and downs reflect political and economic changes. In 2003, for instance, when the Asturian Francisco Álvarez Cascos was public works minister, the government tendered the Pajares project, comprising 50 kilometers of building work including the tunnels. On February 21 of that year, the Cabinet authorized the project, designed on a one-billion-euro budget and a five-year deadline.

In February 2004, Cascos and Economy Minister Rodrigo Rato laid down a symbolic first stone. There was a month to go before elections. Cascos boasted about the project. With every new speech, investment grew. By 2010, Cascos predicted, the Oviedo-Madrid trip would take just two hours and 12 minutes.

"We were fresh off the Guadarrama tunnels [in Madrid], which had turned out well," says a geologist who worked on the project. "But the Picos de Europa are much more complicated. For the work on the tunnel of Saint Gotard [57 kilometers under the Alps] they spent 10 years on the preliminary studies. Over here, with just a few months they thought it was enough."

The final cost is more than 60 million euros per kilometer of tunnel

In July 2005, Socialist Prime Minister José Luis Rodríguez Zapatero was on hand the day that the tunneling machines were first set in motion. Up to five machines were working simultaneously, but the trouble soon began. In November, one of them was stopped in its tracks by a sudden burst of water and mud from an aquifer it had hit - a setback that occurred on two more occasions in January 2006.

"These were the first in a series of water-related incidents that have been occurring since then on all excavation fronts," reads a report drafted some time later. That was when Adif commissioned a detailed hydrogeological study. Essentially, the machines were going in with no exact knowledge about the location of the aquifers, despite this being a rainy region with a karst topography characterized by sinkholes and crevices, which pull rainwater underground.

Another engineer who worked on Pajares feels that this would have been the right time to halt construction and decide how the tunnels were going to be waterproofed. This source points to an additional problem: the division of the workload into four separate sub-projects led by different companies, which made it hard to take a big-picture approach to the problem.

They spent just a few months on the studies and thought it was enough¨

For four years, hydrogeologists from a consulting firm called Ineco went over the ground carefully. A summary of their conclusions reveals that by then, it was too late. "The first specific hydrogeological studies were conducted during the construction phase. The water volume captured by the Pajares tunnels in January 2007 was around 280 liters per second, increasing to 480 in May 2007."

The leaks were starting to affect the aquifers. "Some sources dried up and the odd village had to resort to tanks of water brought in from outside," reads the report, which mentions 13 brooks with water-supply problems. The study includes photographs taken inside the tunnels, with two large jets of water clearly visible. Other sources claim the material used to affix the tunnel walls to the rock was not good quality, which makes the waterproofing all the more expensive.

Evidence that the problem had barely been considered at all is in the environmental impact statement of 2002, which did not concern itself with the underground water. Hydrogeologists revealed that construction work had perforated 20 aquifers and that the tunnels were draining as much water as carried in the summer by the entire Bernesga River, on the León side of the mountains. Since the tunnels slope toward Asturias, the water runs north. As a result, there is a hidden, subterranean water transfer of between 10 and 12 cubic hectometers a year from the Duero river basin to the Cantabrian Sea.

Carlos González Antón, a law professor in León, warned in 2009 that this underground water transfer is against the law and announced he would be taking the case to the European Commission on behalf of a local association.

Sources dried up, and villages had to resort to bringing in tanks of water¨

The residents noticed it straight away. Óscar Gutiérrez Álvarez, mayor of Villamanín, one of the municipalities suffering from water loss, says that nobody warned them about what was coming: "They gave us no explanations. [...] When you do things wrong from the beginning, they end up badly."

Fernando Castañón, the cattle rancher, remembers his disputes with the engineers. "They said that once they sealed the tunnel, the water would return, and I said that was impossible. One of them got mad and said that considering how much I knew, it was odd I hadn't been appointed worksite manager by Adif. But the water left, and it's not coming back."

But he knows that his is a lost cause. "They decided that in order to bring the AVE to Asturias, which has over a million people, the few people who live in these valleys had to be screwed over. All right. But they didn't do things right, and they're not going to waterproof the tunnel. Asturias has no AVE, and no water."

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