The objective of the consultancy was to undertake a comprehensive safety review of Alto Anchicayá Dam (140 m high concrete-face rockfill dam), Salvajina Dam (148 m high concrete-face rockfill dam) and Prado Dam (90 m high embankment dam).
The activities carried out for all three dams comprised:
- Field investigations to verify the mechanical properties of the materials and soils.
- Geological and geomorphological analyses and geotechnical studies of the dams.
- Statistical analysis and modelling of dam instrumentation data.
- Structural modelling of the three dams using three-dimensional stress–strain models developed with FLAC software.
- Qualitative risk analysis through Failure Mode Identification and quantitative risk analysis using risk models.
- Preparation of a final report containing all the consultancy results.
The following additional activities were undertaken for Alto Anchicayá and Prado dams:
- Flood estimation and analysis based on a detailed hydrological study.
- Reassessment of the hydraulic capacity of the outlet structures using a three-dimensional computational fluid dynamics (CFD) model.
- Two-dimensional hydraulic modelling of the downstream areas using HEC-RAS and preparation of flood risk maps for different dam-break and release scenarios.
- Assessment and optimisation of the gate operation protocol.
