Front matter for Highway 1 Rat Creek Embankment Failure

Beyond Failure: Forensic Case Studies for Civil Engineers, by Norbert J. Delatte, Jr. (ASCE Press 2009). Norbert Delatte presents the circumstances of important failures that have had far-reaching impacts on civil engineering practice, organized around topics in the engineering curriculum. (ISBN 978-0-7844-0973-2)

Edenville and Sanford Dam Failures: Field Reconnaissance Report, edited by Daniel Pradel and Adam Lobbestael. (ASCE/GI 2021). GSP 327 presents the results of on-ground and aerial assessments of the Edenville and Sanford Dam failures of 2020. (ISBN 978-0-7844-1576-4)

Engineering Methods for Precipitation under a Changing Climate, edited by J. Rolf Olsen and Kelcy T. Adamec. (ASCE/CACC 2020). This collection contains seven peer-reviewed papers on engineering design for precipitation extremes presented at the ASCE Workshop on Engineering Methods for Precipitation under a Changing Climate, held in Reston, Virginia, May 30, 2017. (ISBN 978-0-7844-1552-8)

Failure Case Studies in Civil Engineering: Structures, Foundations, and the Geoenvironment, Second Edition, edited by Paul A. Bosela, Pamalee A. Brady, Norbert J. Delatte, and M. Kevin Parfitt. (ASCE/Forensic Division 2012). This special publication consists of a collection of short descriptions of failures case studies in civil engineering. (ISBN 978-0-7844-1255-8)

Monitoring Dam Performance: Instrumentation and Measurements, Task Committee to Revise Guidelines for Dam Instrumentation; edited by Kim de Rubertis. (ASCE/Energy Division 2018). MOP 135 provides practical information on the process of using instrumented monitoring to determine how well a dam is performing. (ISBN 978-0-7844-1482-8)

The last two decades have revealed the vulnerability of US infrastructure to intense rainfall, storm surges, flooding, wildfires, slope movements, and construction activities. The disastrous consequences, both human and economic, of these extreme events are frequently caused by the failure of embankments, highways, dams, slopes, levees, retaining walls, and flood control structures. Many of these structures and failure modes fall within the area of expertise of the Embankments, Dams, and Slopes (EDS) Technical Committee of the Geo-Institute (GI) and can provide members with important lessons for designing and constructing more resilient infrastructure. As a result, the EDS Committee requested funding from the GI to investigate two (2) major extreme events involving embankments, dams, slopes, levees, and other structures per year. The GI funded this proposal and the reconnaissance of the Edenville and Sanford Dam failures was the first event investigated under the funding provided by the GI in May 2020. The GI funds are only used to reimburse travel, testing, or investigation costs with an emphasis on encouraging younger EDS members to participate in the reconnaissance teams. Additional costs are borne by other committee members who are selected to participate in the reconnaissance trip. The deliverables for each reconnaissance trip are (1) a report on the reconnaissance trip and recoverable perishable information published by the GI as a Geotechnical Special Publication (GSP), (2) a presentation during the annual GI Web Conference and/or annual conference, and (3) an article for GeoStrata magazine. All these deliverables have been completed for the Edenville and Sanford Dam failures. The EDS Committee gratefully acknowledges the support provided by the GI that has allowed committee members to learn from field observations after extreme events and improve future infrastructure performance.

For this investigation, the team gratefully acknowledges the support provided by the California Department of Transportation (Caltrans) in arranging and hosting the site visit, providing extensive information on the Rat Creek embankment failure, and offering historical information about Highway 1. Caltrans also provided many current and historical photographs of Highway 1 that were instrumental in establishing the methods of construction and the historical performance of Highway 1.

Dimitrios Zekkos, Co-lead, University of California at Berkeley

Timothy D. Stark, Co-lead, University of Illinois at Urbana-Champaign

Parker Blunts, University of California at Berkeley

Reid Fisher, Cal Engineering and Geology

Phillip Gregory, Cal Engineering and Geology

Jhih-Rou Huang, University of California at Berkeley

Kenneth A. Johnson, WSP USA, Inc.

Ozgur Kozaci, InfraTerra, Inc.

Justin Lindeman, Cal Engineering and Geology

John Manousakis, Elxis Group

Nicholas Sitar, University of California at Berkeley

The reconnaissance team gratefully acknowledges the support provided by Ryan Turner, of Caltrans in arranging and hosting the site visit, providing extensive information on the Rat Creek Slope failure, and offering historical information on Highway 1. Caltrans also provided many current and historical photographs of Highway 1 that were instrumental in establishing the methods of construction and historical performance of Highway 1. The reconnaissance team also acknowledges the information and photographs provided by Dave Nelson and Big Sur Kate (https://bigsurkate.blog/).