Bonn The municipal civil engineering bureau has installed a new ventilation system in the Bad Godesberg tunnel at a cost of around eight million euros. In the event of a fire, garage-sized shafts ensure greater safety for motorists.
The construction work in the Bad Godesberg Tunnel took more than a year. On Saturday morning, it is expected that drivers will once gain be able to use both lanes in both directions. The municipal civil engineering bureau has taken the requirements of today's fire protection standards into account and modernized the safety technology accordingly. This meant major restrictions for motorists at times, as Peter Esch, head of the civil engineering office, admits.
Nevertheless, the engineer is satisfied: "We stayed fully on schedule and on budget with the work," he says proudly. The tunnel, which was renovated at a cost of around eight million euros, will even be reopened a few weeks earlier than planned, which makes Esch happy.
From August 2018 onwards, work was initially carried out in the Rhine-side tunnel going towards Bonn. Single-lane traffic going both directions was routed through the other side of the tunnel. In June 2019, the situation changed as they began work on the other side of the tunnel, opening the Rhine-side tunnel for single-lane traffic. Finally, the entrances and exits from and in the direction of Heiderhof/Muffendorf and Friesdorf were closed. The reason: In these sections the last so-called jet fans had to be installed before Friday evening. "We adapted the entire ventilation technology to modern standards," explains Esch.
Better protection against fires in tunnels
The new system is able to react selectively to fires and quickly extract smoke from the tunnel exactly where the fire breaks out. This means that the smoke can no longer spread throughout the entire tunnel, but escapes through openings in the ceiling that are normally closed with blinds and are as large as garage doors. There are 13 such openings per tunnel. At the same time, according to Esch, fresh air is supplied throughout the tunnel. The complete escape route signage has also been revised. According to Esch, the new ventilation technology was developed after witnessing the devastating fires in Alpine tunnels, among other places. "This does not mean that the Bad Godesberg tunnel was previously unsafe," assures the head of the civil engineering office. "We are only smarter today than we were then and have been able to increase safety once again".
According to Esch, the modernization of the safety technology was the largest and longest project to date in the Bad Godesberg tunnel, imposing the most severe restrictions on car traffic since it was opened in 1999. Around 40,000 vehicles pass through the tunnel every day. Especially on the Bonner Strasse to the north, there were many traffic jams during the construction work - and there were a lot of complaints. Esch: "Many motorists did not follow our recommendation to take a detour, but turned off over Elsässer Strasse, which was the main reason for the traffic jams". According to Esch, setting up the detour was already a “colossal effort". In previous years, the civil engineering office had only found it necessary to close the tunnel on a few weekends due to technical problems. The regular maintenance work once or twice a year took place at night and was hardly noticed by motorists.
(Orig. text: Lisa Inhoffen; Translation: ck)