PLENARY 4: Keynote Speaker: Dam and Levee Barrier Walls at the Corps of Engineers: Historical Review and Current State of the Practice-Video

Video Transcription

Video Summary

The presentation traced the U.S. Army Corps of Engineers’ use of barrier walls to control seepage in dams and levees, highlighting how construction methods and quality controls have evolved through collaboration with industry.<br /><br />Case studies illustrated key lessons. At Mud Mountain Dam, severe slurry losses during construction led to pre-grouting and improved monitoring of wall verticality. At Wolf Creek Dam, early barrier walls failed to address all seepage paths; later rehabilitation used pre-grouting, protective concrete panels, pilot holes, verification drilling, and digital data management. At Herbert Hoover Dike, performance-based specifications enabled contractors to use several methods suited to varying geology. Monitoring and testing showed that some wall cracks did not undermine performance. Levee projects in California likewise demonstrated the importance of selecting methods based on subsurface conditions, utilities, and space constraints.<br /><br />Across projects, the Corps emphasized adequate wall depth and length, test sections, rigorous verification, effective data management, and frequent communication among owners, designers, contractors, and sponsors. Risk assessments guide decisions about whether barrier walls or other measures are appropriate, and risk is reassessed after construction.<br /><br />In the discussion, participants raised questions about long-term performance of low-strength wall materials, wall alignment, and permeable seepage-control alternatives. Corps representatives noted that alternatives are evaluated project by project and described ongoing work to develop permeable solutions. They also discussed monitoring Lake Okeechobee during Hurricane Milton and the still-evolving assessment of Hurricane Helene’s damage. The speaker stressed that the Corps has substantial infrastructure work ahead and needs industry expertise to deliver it.

Keywords

U.S. Army Corps of Engineers

barrier walls

seepage control

dams and levees

Mud Mountain Dam

Wolf Creek Dam

Herbert Hoover Dike

pre-grouting

quality control

risk assessment