Seismic retrofit work was identified as necessary in a completed risk-analysis and corrective action study done by USBR and reviewed by a board of independent consultants. Work to lower the groundwater table will facilitate the planned excavation work downstream of the dam to replace potentially liquefiable materials in the dam foundation with stronger and denser material while also reducing potential risks associated with a significant seismic event in the meantime.
Drilling at the dam is scheduled to begin in mid-August and continue through the spring of 2011. Several exploratory holes will also be drilled near the spillway and on the upstream face of the dam as part of the on-going field investigation.
Part of the Weber River Project, Echo Dam – a 158ft high zoned earthfill structure – was constructed between 1927 and 1931 to help supply supplemental irrigation water to approximately 109,000 acres of land west of the Wasatch Mountains. Echo Dam is operated by the Weber River Water Users Association.
