Doubling the track will facilitate an increase in capacity on the lines towards Liège (Belgium) and Trier (Germany).
The current Pulvermuehle viaduct crossing the Alzette valley between the North exit of Luxembourg station, and the plateau du Rham are a bottleneck as they make up the sole exit for trains going to the north and east of the country out of Luxembourg station.
At present, two separate lines run across this bridge:
In order to increase capacity on these two lines at the exit of the station, while keeping in mind that the section of the line Luxembourg-Sandweiler, currently a single-track line, is scheduled for doubling within the framework of the project under investigation, it is necessary to separate the Luxembourg-Troivierges and Luxembourg-Wasserbillig lines right from the exit of the station. This way, there will be four tracks beyond the north exit of Luxembourg station: two tracks on the viaduct towards Troisvierges and two tracks on the viaduct currently under construction towards Wasserbillig. This new viaduct will run along the north-east side of the existing viaduct.
As mentioned before, the line towards Wasserbillig presently only has one track at its disposal between the Pulvermuehle viaduct and Oetrange station. The two lines only cross over at Sandweiler-Contern station. Therefore, doubling the track will improve punctuality of the trains to and from Wasserbillig.
The planned doubling of the line is also the logical next step in the construction of the viaduct above. It should also be mentioned that the line towards Wasserbillig is the only railway line between Luxembourg and Germany.
As has already been mentioned above, the project to double the track will begin once the construction of the new viaduct now under way has been completed. The railway line will firstly turn to the right towards the east. The first part will pass between the high rock faces towards the north of the area of Cents. After its last bend, the line will continue its route on a hill when in the south it will connect Pulvermuehle with the Irrgarten roundabout. After a long straight line, it will come to the stop in Cents-Hamm. After passing the last buildings in Cents, the line will turn to the right again to avoid the Irrgarten A1/N2 motorway junction. It will pass over the A1 motorway and cross the forest to the bridge spanning road CR 159 connecting Itzig to Sandweiler. When the bridge was renewed, it was already enlarged in order to facilitate the laying of a second track, which is the aim of the current project. After passing the water reservoir along the road and having crossed the Contern industrial zone, the line will reach the station of Sandweiler-Contern, the sole current crossing point between Luxembourg and Oetrange.