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Rijnland Route Updates


On 01/09/20 after 3.5 months of excavation and a month ahead of schedule, the TBM called Gaia completed the second tunnel tube for the Rijnland Route. The TBM covered a distance of 2,250 m, from the launch shaft by the A4 to the Stevenshof district of Leiden (A44). 


The new tunnel on the N434 has been named as the Corbulo tunnel. This is in honour of the Roman general Corbulo, who ordered the construction of a canal between the Rhine and the Maas in 47 BC. The Rijnland Route has Roman connections - the tunnel on the N434 under the Rhine-Schie Canal dates from Roman times. And along the N206 ir. G. Tjalmaweg near Valkenburg (also part of the RijnlandRoute), almost 500 oak foundation piles have been excavated from the Roman border road that ran along the Oude Rhine. 

In October Comol5 reached another milestone, completing all the tests for the main technical systems, including the lighting, CCTV cameras, emergency telephones / intercoms, ICT network and the speed underrun system (SOS).  This has been achieved two years before the full opening of the Corbulo tunnel.

TBM dismantling work has been delayed due to a leakage at the tunnel mouth which damaged parts of the concrete wall. Once dismantling is finished  The valuable parts will go back to the TBM’s factory in Germany to be re-used for new TBMs and the remaining material will be recycled.

For further information please click here and nl/41 for the tunnelbuilder archive and also visit https://rijnlandroute.nl and https://www.comol5.nl/. 47/20.