Constructed in 1953, Lake Isabella Dam consists of two primary embankment dams located on the Kern River east of Bakersfield, California. With severe seepage and seismic deficiencies, the dam is one of the highest-risk dams among the U.S. Army Corps of Engineers’ (USACE) inventory of more than 600 U.S. dams.

Reexamining Regulations

A dam breach related to seepage and seismic deficiencies could result in significant downstream flood inundation that would affect people and properties in less than four hours. The USACE Sacramento District is evaluating these deficiencies and developing solutions for rehabilitating the dam while addressing new and changing pre-existing risk-informed regulatory guidelines. Recommendations for dam rehabilitation were submitted in in late 2011.

Investigation and Improvement

As a member of a joint venture team, Kleinfelder assisted the USACE with site investigations, site characterization, structural performance monitoring, and seepage and seismic analysis. Kleinfelder performed geologic and dam safety investigations, as well as seepage modeling and performance-based calibration of the seepage model. Working closely with joint venture partners and the USACE, Kleinfelder helped the USACE meet the new risk-based requirements using cutting-edge risk analyses processes to redesign and modify recommendations where needed.

Project Results

Since 2009, Kleinfelder has provided continuity to the project while helping the USACE meet an accelerated schedule in a demanding, changing regulatory environment. Kleinfelder assisted the USACE in identifying Potential Failure Modes, helping to rank each on the basis of risk and consequence in order to prioritize critical path rehabilitation concepts.

Project Details

Location:
Kern County, California

Owner:
U.S. Army Corps of Engineers, Sacramento District