Tunnel Drainage Management
Critical groundwaters & scale deposits
Expertise on tunnel waters, sinter formation, building material contact & alteration
Scale deposits (sinter crusts, ochre, biofilms) from critical groundwaters and waters interacting with the tunnel infrastructure (concrete/construction material contact) constitute a challenge regarding an undisturbed operation and maintenance of railway and road tunnels. The mineral and organic deposits (calcium carbonates, iron oxides, bacteria) block various and partially inaccessible components of the tunnel drainage system and hence of groundwater influx and outflow. Construction materials can be altered from localized and unfavorable chemical processes. The expertise concerns the planning and operation stages of tunnel infrastructure equally.
Custom-made problem solutions
Tunnel Drainage Management (TDM) targets a tunnel-specific process understanding and effective strategic solutions. Every tunnel hosts individual and interacting natural and technical environmental conditions. This involves geology and hydrology, hydrochemistry and air exchange, construction options, materials and flow geometries, and the local microbiology and scale (sinter) formation potentials. The variable conditions affect and alter the building materials and determine the evolving scale deposits.
TDM concerns constructive as well as operative measures and consists of different modules (see below) which can be activated as required and to a variable extent. The approach can be integrated into geotechnical planning and implementation, into geological tunnel documentation or maintenance procedures of tunnel infrastructure.
TDM is conducted in cooperation with the Institute of Applied Geosciences at Graz University of Technology and with the geotechnical (tunnel planning) division of GC and is based on the interdisciplinary range of services and broad expertise available within GC GROUP.

Fester Sinter Poröser Sinter
Services in a nutshell
- Assessment of current state & layout of drainage system (inventory or new construction)
- Mapping & sampling strategies of scale (sinter) deposits, analyses of fluids & solids
- Computer-based modeling of hydrochemical conditions, gradients & processes
- Assessment of tunnel waters, scale/sinter potentials, concrete/construction material contact & alteration, key sections
- Active measures: optimized drainage implementation (components, materials, geometries) & water hardness stabilization (agents/additives, products, dosage)
- Monitoring using modern sensors & dataloggers (in-situ, online)
- Advice & recommendations: operation, inspection, maintenance & cost optimization
- Training/Workshops on TDM