Construction and Monitoring for a State of the Art Foundation Grouting Program at Rough River Dam-Video

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Video Summary

Stephen Shifflett, lead engineer for the Rough River Dam project in Kentucky, described exploratory foundation grouting conducted from 2015 to 2017 ahead of a future cutoff wall. The dam’s karstic limestone foundation and retained alluvial soils had shown changing piezometric conditions and increasing seepage after high reservoir levels.<br /><br />To protect dam safety and guide grouting, the team installed an automated monitoring system with 58 vibrating-wire transducers, used staged drilling and grouting, and monitored injection and grout-column pressures. Downhole geophysics helped identify voids, grout losses, and improve subsurface records. Real-time coordination between the owner and contractor supported timely adjustments to grout mixes and operations.<br /><br />Grouting reduced permeability through primary, secondary, and tertiary stages, though it was not intended to achieve closure. Post-grouting measurements showed improved pressure response in the alluvial soils, but some reservoir connectivity remained, particularly near the outlet conduit and potentially compromised rock-soil contact. The presentation emphasized the value of detailed instrumentation and monitoring during foundation grouting.

Keywords

Rough River Dam

foundation grouting

karstic limestone

seepage control

automated monitoring