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Spain and Morocco Revive Fixed Link Project under Gibraltar Strait

Spain and Morocco Revive Fixed Link Project under Gibraltar StraitThe project to link Spain and Morocco with a tunnel beneath the Gibraltar Strait has been revived at a recent summit held on 9th December in Marrakech between Spanish minister of public works Francisco Álvarez Cascos and Morrocan minister of equipment and transport Karim Ghellab. The governments of both countries have agreed a three-year working plan (2004-2006) with a budget of €27 million to refine the studies on the tunnel. 84% of this amount (€22.7 million) will be spent on submarine core drills to analyse the geology to determine the best drilling route. The studies will be carried out by the two state companies, SECEGSA (Sociedad Española de Estudios para la Comunicación del Estrecho de Gibraltar) in Spain and SNED (Société Nationale des Etudes du Détroit) in Morocco.The construction of the tunnel would commence in 2008 at the earliest. To date, Spain and Morocco have determined the tunnel route, that will go from Punta Palomas, 40 km west of Gibraltar, to Punta Malabata near Tangiers (see map). This was chosen because the Mediterranean Sea at that point is only around 300 m deep and the tunnel would be dug 100 m under the seabed. This option was preferred to a shorter route between Punta Canales in Spain and Punta Cires in Morocco which offers the advantage of being only 14 km in length under the sea (28 km for the selected alignment) but would oblige to excavate at a 900 m depth.In the chosen alternative, the total tunnel length would be 38.7 km, of which 27.7 km subsea, to an approximate depth of 100 m. The planned solution is for a double tunnel similar to the Channel tunnel, 7.5 m in diameter, linked by a 4.8 m-diameter service tunnel in the middle. Nevertheless, the final route and the depth of the tunnel would depend on the geological and geotechnical studies and a complex series of deep tests that are to be carried out. The required investment is estimated at €3 billion.Among the most relevant assignments within the Spanish-Moroccan agreement is a preliminary study for tunnelling feasibility. The basic objectives will be to evaluate, based on the available geological and geotechnical engineering, the problems related to tunnelling through the existing geological formations. The draft project will also be reviewed to determine the ground elevations, the longitudinal profile, the lining type, the estimated budgets, and finally the general planning. The aim is to define the most accurately possible the parameters that will have to be developed for construction purposes in the detailed design studies.Preliminary works have already been done to analyse and test the characteristics of the existing ground in the project area on each coast. These works include the test tunnel in Tarifa, a 560 m-long 3.8 m-diameter tunnel situated near the north entrance to the future tunnel, and the 300 m-deep Malabata shaft near Tangiers. 02/04.