THE ARCHIVE

When fully completed, the new line will stretch for almost 48 kilometres, making it the longest line in Europe and the longest metro line in the world of entirely new construction. It is also the most expensive enterprise the Catalan government has ever undertaken. The original projected cost was €2.25 billion, but it will wind up costing €6.5 billion, according to a recent La Vanguardia article.

The L9 will run clear across Barcelona from Can Zam in Santa Coloma to the Zona Franca on to the El Prat airport, with its L10 branch line going from Gorg in Badalona to the Nova Estació Poligon Pratenc. While the first five of its total 52 stations opened in December 2009, the estimated date for the line’s completion won’t be until some time in 2014, according to the latest estimates.

“Tunnel builders know that you sometimes know when you’ll begin a tunnel, but you never know when you’re actually going to finish it,” said Henning Schwarz, director of the geo-technical and monitoring department of GISA, the Generalitat’s public company that manages all major public construction, including that of metro lines. He said security in construction always has first priority.

The challenges facing the tunnellers in Barcelona’s metropolitan area are daunting. They must bore through highly varied geology, ranging from solid rock to soft sand and everything in between. The route passes beneath both of the city’s rivers, and lies below sea level in areas by the port. The project must proceed with the utmost care as it digs beneath the densely populated surface areas of the city. “Everybody wants a metro stop near their home, if possible,” Schwarz recently told Metropolitan. “But nobody wants it directly beneath them.”

The concern is understandable, given the ground destabilisation that occurred a few years ago in the Carmel neighbourhood during work on extending the L5 metro line. Although the only structure that actually collapsed at the time was a car park, hundreds of residents had to be temporarily relocated as a preventive measure, some for almost two years. At any rate, the officials at GISA said that extreme caution is being used as they tunnel below Barcelona’s busy surface.