The Challenge

Persistent Leakage in Historic Railway Tunnel

The Neuer Kaiser Wilhelm Tunnel—over 4.2 km long—is a critical railway corridor along the Moselle River, connecting the Cochem region to Germany’s wider transport network. Despite modern rehabilitation, sections of the tunnel developed persistent water ingress, especially:

Along construction joints in the invert and walls
At interfaces between old and new lining structures
In microcracks resulting from settlement and seasonal movement

The leaks caused:

Standing water on the track bed, risking safety and compliance issues
Increased maintenance costs and drainage pump operation
Degradation of concrete and corrosion of steel fixtures
Operational challenges due to the high-traffic nature of the tunnel

Standard cement grouting had limited success sealing dynamic, saturated cracks without impacting train service.

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The Solution

EURAS® Gel Type B – Flexible Waterproofing for Transport Tunnels

After thorough evaluation, EURAS® Gel Type B was specified due to its:

Self-penetrating hydroscopic action, displacing water in live leaks
Compatibility with wet and variable-thickness concrete linings
Elasticity to accommodate ongoing settlement and movement
Non-toxic, non-shrinking composition suitable for transport environments
High-pressure injection capability for deep crack sealing

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Execution Methodology

Implementation Details

The project was performed in scheduled night closures to avoid disrupting rail traffic:

Mapping and marking infiltration areas using moisture detection and borehole cameras
Installation of injection packers along walls and invert joints
High-pressure injection of EURAS Gel Type B up to 180 bar to saturate cracks and cavities
Monitoring gel flow and back-pressure for confirmation of fill
Final watertightness verification before reopening to traffic

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