Location: Jijel, Algeria
This tunnel belongs to a larger modernization project of the coast roadway between Jijel a Bejaia: RN 43 motorway. This comes from the need to avoid the current road along the coast whose section is significantly reduced in proximity of the famous Wonderful Cave and would have end up in a small natural single-track tunnel. Such redevelopment works would have been clearly been a threat for the Wonderful Cave as well as for the whole remarkable cliff overlooking on the seaside. Therefore the decision was to create a new tunnel, above the current route, which goes through Jebel Hamra calcareous mass towards the sea-side. This allowed to avoid the famous site and to not affect the wonderful natural coast.
SGS prepared the design work for the new 600m tunnel and a new viaduct at Wadi Dar el Oued. Tunnel has a polycentric cross section with a bottom slab; maximum cover height is about 140m.