Dam Safety Instrumentation Performance of Boone Dam during Remediation Grouting-PPT Presentation

PPT Presentation

Pdf Summary

The presentation reviews dam-safety instrumentation at Boone Dam during remediation of internal erosion, focusing on performance trends during construction and reservoir filling rather than individual instrument readings.<br /><br />Following discovery of a sinkhole in 2014, remediation included a tailrace filter, test and production grouting, upstream and downstream berms, a cutoff wall (COW), and floodwall and crest restoration. The work was accompanied by extensive piezometer monitoring.<br /><br />Instrumentation showed that grouting in 2016–2017 changed groundwater gradients across the embankment baseline. Additional reduction in seepage through the epikarst—weathered rock beneath the dam—was observed during cutoff-wall construction. Piezometric fluctuations were largely associated with rainfall, and a downward trend beginning in late 2019 was linked to lower rainfall and changes in stormwater management.<br /><br />During reservoir refill in 2021, the largest epikarst head differences occurred upstream of the cutoff wall, as expected. Changes downstream of the wall and within the right rim were negligible, with no increases observed; seasonal effects were evident in some downstream and right-rim instruments. The mapped epikarst groundwater flow was predominantly east-to-west, with gradients influenced by heavy rainfall.<br /><br />Overall, the presentation uses the monitoring data to describe how remediation and environmental conditions affected groundwater behavior, providing evidence that can inform assessment of dam performance during and after construction.

Keywords

Boone Dam

dam safety instrumentation

internal erosion remediation

piezometer monitoring

cutoff wall

epikarst groundwater

reservoir refill

groundwater gradients

seepage reduction

embankment performance