Spain and Portugal for Visitors

Posted by : John Ross on Mar 08, 2007 - 11:12 AM railways

The prime ministers of both countries have declared their intention to carry through with the project for a Europe-Africa rail tunnel. The plan is not new - a tunnel under the Straits of Gibraltar between Spain and Morocco has been officially under consideration since at least 2003 - but the joint announcement reflects recent progress towards this end. A Swiss firm, Lombardi Engineering, was commissioned to produce plans for the tunnel last year, and the project was presented in Rabat on Tuesday, March 6 2007, at the end of a visit by Spanish head of government José Luis Zapatero. Read more.

The economic benefits of a tunnel to both Spain and Morocco and to their neighbours are evident. The costs, however, will be enormous, and Zapatero insists that he will work to raise European Union funding. Private investment is also likely to be sought.

At first sight, the tunnel would seem similar to the Chunnel which now connects Great Britain and France, indeed, the intention is that it should also be a double railway tunnel, and the distances involved are similar, or smaller. However, the engineering obstacles are more daunting. For one thing, the depth of the Strait of Gibraltar (300 to 900 metres) is greater than that of the English Channel (45 to 150 metres), and the route chosen for the tunnel is twice as long as the shortest distance across the strait to keep the depth of the tunnel as low as possible. What's more, the sea bed of the Strait of Gibraltar is soft, even muddy, and the tunnel will have to be bored another 100 metres down. The pressures at this kind of depth mean the tunnel will unavoidably "leak heavily, no matter how well it is built," according to Lombardi's project engineer Andrea Pancieri, as unreassuringly reported by various media sources, including the Washington Post.

The earliest possible completion date I have heard is 2025, so the Algeciras ferry will continue to be the main connection between the two countries for a while to come. And I predict that, although the tunnel will, eventually, be built, even more serious difficulties will be encountered in its construction. It will be built because the need for such a connection between Europe and Africa it is far greater than the relatively insignificant interests of Spain and Morocco. And huge obstacles will arise because it will not just be another, engineering record-breaking feat. It will connect continents, not far from a depth where tectonic plates regularly wrestle with each other, and across a major earthquake fault line at that. This is not just a tunnel, it's Jules Verne territory.