Owner's Perspective: Addressing Seepage Issues During Dams Normal Operation

Eagle Mountain Lake, a major water supply reservoir for Fort Worth, Texas had experienced chronic seepage issues for decades. A five-year preconstruction study collected site data through geotechnical borings, lab testing, topographical surveys and field instrumentation. Four years of monitoring the site helped with understanding the groundwater regimen in relation to lake level variations along with a comprehensive alternative analysis determined a Cutter Soil Mixing (CSM) Wall would be the preferred seepage cutoff system. The 250-ft wall alignment and technical specifications were developed and the contract was awarded in February 2022. This paper will focus on the challenges encountered during construction, including conflicts with existing instrumentation, narrow windows for navigation, steady QA control and presence of existing fill material. This project’s lessons in a