Rehabilitation of the Ituango Dam

The Ituango dam is an embankment dam that is currently under construction on the Cauca River near Ituango in Colombia. The largest hydroelectric power plant in Colombia’s history, the dam measures 720 ft (220 m) tall, will produce 2.4 gigawatts and will produce approximately 13% of Colombia’s energy.

Three, large diversion tunnels used to divert the water from the river around the construction site during construction collapsed as a result of heavy rainfalls. The nearly completed pump house had to be flooded to accommodate premature water build-up in the reservoir. These tunnels would need to be permanently sealed.

“Pre-stoppers” would need to be constructed in place to serve as bulk heads between which would ultimately be excavated and back-filled with concrete to permanently seal the tunnels. Additional to standard anti-washout properties, the grout had to withstand swiftly flowing water and exhibit an extended working time at temperatures above 32 degrees C. A custom grout was developed for this application. In the end, hundreds of grout micropiles were tremied, consuming more than 1,650 tons of grout, to produce the pre-stoppers to complete the remediation. The dam is currently scheduled for completion in 2023.

Learning Objectives:

1. What the Ituango Dam is
2. Why it was built
3. What went wrong
4. How Master Builders solutions supplied a material that met its critical requirements under extreme conditions