Findings of the Oroville Dam Spillway Forensic Investigation: On-Demand

At a height of 770 feet, Oroville Dam is the tallest dam in the United States. On February 7, 2017, a section of the concrete chute slab of the service spillway at Oroville Dam failed during spillway discharge. Several days later, as the California Department of Water Resources was evaluating and managing discharges through the damaged service spillway during a large rainfall event, the emergency spillway activated for the first time in the project’s history. The emergency spillway flow resulted in significant erosion of the hillside below the crest structure, leading to concern for the integrity of the emergency spillway and the evacuation of nearly 190,000 downstream residents. The Federal Energy Regulatory Commission mandated a forensic evaluation of the failure of the service spillway chute and the damage to emergency spillway. This webinar will present the findings of the six-person Independent Forensic Team, including discussions of physical factors, human / organization factors, and lessons to be learned from the incident.

John W. France, P.E., D.GE, D.WRE

President, JWF Consulting, LLC

JWF Consulting, LLC.

John W. France, P.E., D.GE, D.WRE is a registered professional engineer and Diplomate, Geotechnical Engineering and Water Resources Engineer, who is currently practicing as an independent consultant. He received his BS degree in civil engineering from Cornell University in 1973 and received an MS degree in geotechnical engineering from the same institution in 1976. Mr. France has over 45 years of consulting engineering experience, during which time he has been responsible for the analysis, design, and construction of embankment and roller compacted concrete dams and their appurtenant structures. He has served on senior technical review boards and panels for dam safety projects for the U.S. Department of the Interior, Bureau of Reclamation; the U.S. Army Corps of Engineers; BC Hydro and Brookfield Renewable Energy. Mr. France has been a consultant to the dam safety programs of the Bureau of Reclamation and the U.S. Fish and Wildlife Service for over 30 years. He has served on Independent Review Panels, who have conducted annual review of Reclamation’s dam safety program, and he served on similar review panels for the dam safety programs of the National Park Service and the Bureau of Indian Affairs. Mr. France was the team leader for the Independent Forensic Teams tasked with investigating the 2017 Oroville Dam spillway incident and the 2020 failures of Edenville and Sanford Dams, and he chaired a five-person team for a review of the dam safety risk analysis practices of the Corps of Engineers, the Bureau of Reclamation, and the Federal Energy Regulatory Commission.




  1. Introduction
    1. Purpose of the Investigation
    2. Investigation Team
    3. Investigation Methodology
  2. Background Information
    1. Oroville Facility Description
    2. Regulatory Setting
      • i.     Federal Energy Regulatory Commission (FERC)
      • ii.     California Division of Safety of Dams (DSOD)
    3. Spillway Descriptions
      • i.     Service Spillway
      • ii.     Emergency Spillway
    4. Chronology of the February 2017 Incident
    5. Service Spillway Chute Design and Construction
    6. History of Service Spillway Chute Repairs
    7. History of Service Spillway Drain Flows
  3. Question Period #1
  4. The Physics of What Happened
    1. Service Spillway
    2. Emergency Spillway
  5. Question Period #2
  6. Why Was This Performance Unexpected
    1. History of Inspections and Regulatory Setting
    2. Geological Evaluations
    3. Chute Slab Repairs
    4. Potential Failure Mode Analyses (PFMAs)
    5. Activation of the Emergency Spillway
    6. Conclusions
  7. Lessons to be Learned


On- Demand Webinar
Open to view video.
Open to view video.
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Completion Certificate
Live Viewing: 2.00 PDH credits and certificate available
Live Viewing: 2.00 PDH credits and certificate available