Yes, this can happen for a short time in cases of traffic management, construction sites or accidents. This may be the case if the maximum authorized speed is limited to 90 km/h at the time a road user enters the tunnel and the CITA changes the tunnel management scenario, following an incident, to a scenario at a lower authorized speed (70 or even 50 km/h). The displays indicated on the signals inside the tunnel are thus modified, while he is crossing it. Remember that the user must always respect the maximum authorized speed indicated in real time.

The law of 21 November 2007 on the minimum safety requirements for certain road tunnels stipulates that in case of a closed lane in a tunnel, this lane must be closed from the tunnel portal on, to avoid over-accidents in tunnels. The same applies to slip roads to tunnels. For example, the slip ramp to the A7 towards Luxembourg from the roundabout Lorentzweiler on the N7 is closed each time when a vehicle is stopped / down on the right lane in the tunnel Grouft towards Luxembourg. As accidents and breakdowns are unpredictable, no prior user information is possible.

Due to the saturation of the traffic on the A7 after the tunnel “Stafelter” in the direction of Luxembourg (during the morning rush hour), it is appropriate to avoid traffic jams on the two lanes within the tunnel “Stafelter”.

In case of a fire in the tunnel, the vehicles, who are blocking the two lanes of the tunnel, can’t leave the tunnel.

Besides, due to the narrowness of such a construction and in case of a traffic jam on the two lanes within the tunnel, it’s not possible anymore to the rescue services to pass through the tube, in case of a fire or an incident in or after the tunnel.

The clothing of the fast lane is therefore a measure of traffic management to guarantee the security of the users of the tunnel.

Much of the information (webcam, travel time, etc.) is available without restrictions and can be easily integrated on intranet or internet sites.

You can find the different datasets on the site data.public.lu

Here is the direct link to the information of our administration:

https://data.public.lu/en/organizations/administration-des-ponts-et-chaussees/

Basically the luxemburgish tunnels are maintained and cleaned twice a year. In comparison, the tunnels abroad are maintained somewhere between once monthly and twice a year. Generally, in one single day, a maximal length of 500 meters can be maintained.

Because of general weather conditions the maintenance work cannot be done in winter period. That’s why it must happen in a limited time area in spring between March and May and in autumn form the end of August until October in order to guarantee at least halfway the 6 months long interval between every maintenance operation. Less maintenance or respectively longer periods in between would mean more unexpected closures.

In these time periods not less than 20 tunnels  have to undergo the maintenance and cleaning process. These maintenance work, like every other road work, is scheduled and organized – if possible – in order to not interfere with luxemburgish, german, belgium, french and dutch holiday periods and other major events. Of course, regarding countless reasons conflicts are not always avoidable.

As a rule of thumb, maintenance operations are scheduled with regard to not nullify the cleaning process and vice-versa. In other words, maintenance is done at night in several tunnels while cleaning is done in the daytime within the realms of possibility. However, the cleaning companies are limited to a period of 3 weeks in which they can execute the cleaning works in these 2 shifts (day/night). These 3 weeks are given as the cleaning companies follow an internal working schedule. There is not much tolerance to postpone these works (1 week maybe). Moreover, for several reasons like organisation, workforce and labour law it is not possible to do the maintenance work on each tunnel at the same time.

Usually a normal maintenance lasts for about 7 to 8 hours disregarding any unexpected problems that must be solved. Despite this, 2 hours before and after have to be considered in order to close the roads and place the deviation signs.

Preventive fire protection an general security requirements are the main points to be considered while maintaining a tunnel. This mainly requires a technical planning of the operations.

1. The overflight by drone or model aircraft of a motorway is forbidden and this within the limits of the enclosures (fences) blocking the access to the motorway also including all the structures, such as bridges spanning across the motorways, the service areas, the interchange ramps, crosses and junctions.
2. The overflight by drone or model aircraft of the “non aedificandi” zone (an area of +- 25 m along the motorway outside the enclosure) is liable to an authorization and consultation with the highways department (CIEA) and introduction of a flight plan (should be addressed to dgt@pch.etat.lu.)
3. In case of authorization, the dates and hours of the overflights have to be submitted at least 24h in advance to the Dispatching of CITA (cita-dispatching@pch.etat.lu and dgt@pch.etat.lu) and if applicable, an appointment with the motorway services is to be foreseen on the location (dgt@pch.etat.lu)

The Location Code List (LCL) was revised in October 2016 by the National Road Authority (NRA).

The version 3 is available free of charge since March 28, 2017 by the NRA (Request at dgt.tmc@pch.etat.lu).

The Location Code List is certified by the European association TISA and will be used for the traffic information service from April 10, 2017.

To obtain the Location Code List you need to accept the conditions of use (Conditions of use).

On the road network, highways, national roads and secondary roads, the accurate location is fixed by two identifiers: the road as such and its kilometric points (PK) or its reference points (PR).

These identifiers are to help road users orient themselves in case of need. The indications are tagged on milestones or road signs.

In this specific case, it concerns the Arlon motorway and the kilometric point 1,5.

CITA (Contrôle et Information du Trafic sur les Autoroutes) is a service of the national motorway department, attached to the National Road Administration (NRA) of Luxembourg (Administration des ponts et chaussées).

Its mission consists in managing the dynamic equipment of the 160 km motorway and the around 20 tunnels, that are constantly connected to the CITA system.

Moreover, CITA supervises 24/7 the motorway network and the tunnels with nearly 600 cameras and almost two hundred thousand other equipments.

CITA coordinates the interventions on site in case of incidents or accidents with a 24/7 permanence presence and informs traffic users about any traffic disturbance directly by dynamic signalization and indirectly through third party services (e.g ACL, 112, Police, foreign Road Administrations,...).

Indeed, the main objective is to avoid further collisions and reduce traffic congestions related to breakdowns. In terms of sustainable traffic management, CITA manages the scope of planning, organizing and surveillance of the yearly 1000 road works to guarantee a wide range of other safety, mobility and environmental benefits.

The entire highway network is encoded. This has been done with the conception of the CITA fifteen years ago. All the equipment which are connected to CITA, are clearly localisable and unique. It is possible to identify a highway by the direction and the “kilometrique point”.

This information is visible on the camera pictures and streams. In reference to the map and with a little bit of practice it is easy to evaluate the localisation of the camera.

For the highway, the following codification has been retained:

• A1 : GT Gasperich-Trier / TG Trier-Gasperich
• A3 : VM Ville-Metz / MV Metz-Ville
• A4 : RH Raemerich (Rédange)-Hollerich / HR Hollerich-Raemerich(Rédange)
• A6 : GW Gasperic-Weyler / WG Weyler-Gasperich
• A7 : FN Fridhof-Neudorf / NF Neudorf-Fridhof
• A13 : PS Pétange-Saar / SP Saar-Pétange

In the event of a “ghost-driver” alert, CITA limits the maximal speed to 50 km/h on the highway section which is concerned and publishes the following message on the variable message signs “Attention voiture en contresens, serrez à droite”, until the moment when it’s proved that the danger exists no more.

No - CITA does not record images of video surveillance cameras.

The traffic situation overview is illustrated as follows:

• Green : fluid traffic
• Orange : dense traffic
• Light red : slow traffic
• Dark red : traffic jam
• Grey : no data available

The latest technologies in web design make it possible to render the content regardless the screen resolution used by the different devices (PC, tablets, Smartphones). All you have to do is to create a bookmark to connect directly to the cita.lu website.

Constant maintenance and construction work on pavements and highway infrastructure is carried out in order to provide adequate highways for the users. These works are carried out during the night and weekends where possible. Sometimes due to unpredicted situations it's not always possible to finish the work before peak hour traffic.

The administration is aware of the problem and executes regular maintenance work in order to close the potholes.

Timetables are only estimated durations. Due to the importance of works it is sometimes impossible to precise the exact duration . Consideration must be taken for site preparation, time needed to secure an area can take up to 3 hours.

Information concerning construction sites for national road network is not always available to CITA .

Please contact either the department of Luxembourg Division des services régionaux LUXEMBOURG- (DVL dvl@pch.etat.lu - tél.: (+352) 2846 - 2100) or Diekirch ( Division des services régionaux DIEKIRCH – DVD dvd@pch.etat.lu - tél.: (+352) 2846 - 3100) or the municipality in charge.

The Administration des ponts et chaussées manages only a few traffic lights near major interchanges.

The majority of traffic lights falls under the responsibility of the competent municipality.

CITA noticed that drivers do not always respect the red emergency lights at the tunnel entrance (used in the event of traffic pile ups, jams and accidents etc). In order to indicate the halt zone, white STOP lines have been added at the tunnel approach zone.