Modeling of Natural Dam Leak and Candidate Mitigation Measures

The natural rockfall dam that creates Zeballos Lake was leaking—with no obvious source or path of the leak, Kruger Energy Inc. (Kruger) needed to find a way to minimize the leakage. They reached out to us for help.

For this Phase 1 study, we set out to do a few things. First, it was important to identify the source, or sources, of leakage—then we could look at evaluating options to stop it. From there, we facilitated identifying and preliminary evaluation of the candidacy of measures capable of minimizing the leakage—reducing the leakage losses could then make the operation of Kruger’s Hydroelectric Power Project more effective. Using bedrock and bathymetry data collected from the 2015 geophysics study, terrain analysis and existing topography data, as well as completing a rockfall runout analysis, we developed a site-specific geological model. This was the basis for a constructed site-specific hydrogeological model, which incorporated the site stratigraphy. The model was calibrated using data collected in July 2015—with this, Kruger will be able to simulate various future scenarios.

This project was conceived of as an initial fresh look review of all pertinent historic files and initial field investigations. The results of the study will define the scope of work for a Phase 2 detailed development of mitigation measures, ultimately keeping the dam leak-free for years to come.