Hydropower Project
Ethiopia

The Gilgel Gibe II Hydropower project is within the Gibe-OMO system and four turbines housed in an above ground power house provide 420MW of power from 500m of head. Water is fed from the Gilgel Gibe River via a sluice gate and transferred via a 26km TBM excavated headrace tunnel.   Completion of the headrace tunnel was delayed when the intake portal TBM came to a halt on encountering exceptionally adverse ground conditions and high groundwater pressure.

Geo-Design acted as independent assessors of the event and of the scheme planned to bypass the adverse ground conditions.

Sector: Water – hydroelectric power station.

• Geological and hydrogeological evaluation
  Independent evaluation of the large amount of investigation data, inspection of core, evaluation of the rock mass conditions and review of rock mass failure mechanisms.
• Collapse mechanism
  Providing opinion on the mechanism of ground behaviour.
• Root cause analysis
  Establishing the engineering and technical cause of the incident.
• Review of recovery and restart plan