The Oudayas Tunnel and its access roads, are extended from the roundabout of Bab Al Bahr to the Surf Club Oudayas along the ocean side for a total length of 1022 m, and has since its opening to the public on May 2011, allowed the decongestion of the site on the outskirts of the Oudayas.
The Oudayas Tunnel goes through the road of Al Marça along the Kasbah which experience heavy traffic. Indeed, the traffic of motor vehicles reached an average of over 30,000 vehicles per day, including 3,500 heavy buses and heavy trucks.
A tunnel ….A solution
The tunnel construction option found its justification in the will of the Agency of Bouregreg to upgrade the transport infrastructure of the sequence I, but also to compensate the deterioration of the level of service and the security on Al Marça road.
Similarly, the nuisance caused by the heavy traffic in this very sensitive areas (historic site and mostly touristic) had become increasingly untenable in addition to more risks of accidents with serious consequences.
The tunnel and its pathways consist of several parts: an underground tunnel with two tubes, each tube comprises two channels, realized by excavation in the rock over a length of 290 m. Trenches covered as a double box culvert reinforced concrete along the esplanade and the ocean side over a total length of 200 m, and open trenches supported by diaphragm walls for linear 220 m, and more connections to two roundabouts are to made over a length of 312 m on both sides.
From the beginning of the work, technical constraints were inherent to the realization of a such huge project . These include the passage of part of the project under the historical monuments which need special devices to support recovery , implemented under the foundations of these monuments. Similarly, the project location in an urban setting has imposed various retaining walls to allow the necessary excavations vertically. Several techniques have been used in the project, such as diaphragm walls, the walls “Berlin” and the columns of jet-grouting.
Furthermore, the existence of a groundwter at a high level on the side of the plaza and in the part corresponding to the garden of Oudayas, have required pre-sealing.
All these elements have made out of Oudayas Tunnel, a unique achievement technically.
Launching the project works
The Agency for the Development of Bouregreg Valley, as a project master, has entrusted the implementation of the work, following an international tender, to the Italian consortium Pizzarotti & From Alpi Co.
The project management was provided by the Studies Office group CID (Consulting, Engineering and Development, Moroccan BET) & Lombardi Sa (Swiss BET). Furthermore, the Public Test Laboratory and Studies (LPEE) was in charge of the quality control of the project.
The launch of the tunnel work was held in April 2007 to an estimated completion time of 41 months and a cost of construction and equipment of approximately 500 Million DHS HT.