The overhead contact line system will be renewed in three construction phases over a total length of 25 kilometres. The existing system was built in 1958 and, according to Thomas Kayser, project manager at Deutsche Bahn, is in acute need of renewal. With more than 350 train journeys a day (local, long-distance and freight traffic), the outdated technology between Bonn and Cologne is overloaded. "We had to take urgent action", he says.

In preliminary work, the railway company has already built the foundations for 320 new catenary masts and erected a large number of the new steel masts. During the summer holidays, the fixings and attachments will be fixed to the masts on the line sections from Hürth-Kalscheuren to Brühl, Sechtem to Roisdorf and Roisdorf to Bonn, and the contact and catenary wire will be installed.

Barriers are also being renewed on four bridges in order to better shield the safety area to the new overhead line. According to Kayser, three large specialist companies are working simultaneously on this project. The work is not particularly noisy, and the loudest work phases are to take place during the day.

In addition, according to Kayser, preparatory work for the use of a new train protection technology is still in progress, as well as final work on the noise protection walls in Roisdorf.

According to Deutsche Bahn, the modernisation of the overhead line system will cost 18 million Euro in 2020 alone. The section between Brühl and Sechtem was already renewed in 2018. In 2025, the modernisation of the overhead contact lines in Brühl, Sechtem and Roisdorf stations is on the agenda.

The work now to be carried out will have an impact on local and long-distance traffic. Passengers must be prepared for the following changes:

RE5: The RE5 may be cancelled between Bonn and Sechtem, but replacement buses will be running. During the construction work, the RE5 will also stop in Sechtem for travel to or from the North. In the direction of Koblenz, there will be no stop in Cologne South until 9 August. On July 29th, the regional express also stops between Bonn and Cologne, but there will be a replacement service between Bonn and Hürth-Kalscheuren, with a connection to RE22/RB24.

RB26: The line will be cancelled between Sechtem and Bonn, but buses will be running. Between Cologne and Sechtem as well as Bonn and Remagen the trains will run at slightly different times. From Cologne to Sechtem there will be no stops in Cologne West and Cologne South until 9 August. There will be no night service between Cologne and Bonn. On 29 July the regional trains between Cologne and Bonn will also be cancelled. It should be noted that there will be some line exchanges between Mittelrheinbahn and National Express. National Express takes over some of the RB26's journeys between Sechtem and Cologne-Dellbrück. The journeys of the RE 5 line between Koblenz and Bonn are taken over by the Mittelrheinbahn. Passengers should therefore pay attention to the line designations on the vehicles, as the vehicles of the respective other operator will be used.

RB48: The line RB48 between Cologne and Bonn-Mehlem will not run.

Eifelstrecke: Trains on the Eifel route will run in the direction of Euskirchen without stopping at Köln-West and Köln-Süd. In the morning and in the evening some additional trains are to be omitted.

RB30: The Ahrtalbahn is omitted between Bonn and Remagen due to platform works in Oberwinter.

Long-distance connection: The long-distance trains will not stop at Cologne Central Station, Bonn Central Station, Remagen and Andernach. Alternatively, the trains with changed travel times will stop in Köln-Messe/Deutz, the IC and EC trains additionally will stop in Beuel. There will be no direct ICE connections to and from Berlin between Bonn and Cologne. The ICE trains on the high-speed line on the right bank of the Rhine are not to be affected.

Replacement buses: Between Bonn and Sechtem a rail replacement service with articulated buses will be used. The buses will run every 15 minutes and stop in Bonn at the Colmantstraße/Hauptbahnhof bus stop. Of these, two buses per hour will run as direct buses without a stop in Roisdorf. In addition, there are to be some trips between Bonn and Hürth-Kalscheuren. This concerns sporadic morning and night trips as well as all day on 29 July. On July 29th, direct buses will also run without stops between Bonn and Hürth-Kalscheuren.

NVR managing director Heiko Sedlaczek admitted that there are massive restrictions for passengers. However, he said that the work was urgently needed and that the NVR welcomed any investment in the rail infrastructure.

With stickers, banners and posters in trains and stations, passengers will be informed about the construction work. In addition, according to the NVR, the changes are already reflected in the online information systems.