How the Oroville Dam Failed

April 18, 2017

The LA Times reports the Oroville Dam, as analyzed by Robert Bea at the Center for Catastrophic Risk Management at UC Berkeley, was poorly designed, constructed, and maintained.

The report, Preliminary Root Causes Analysis of Failure of the Oroville Dam Gated Spillway, published online by the LA Times, shows in photos and discussion how so many failures added up to a disaster.

Just a few of the defects and flaws found include:

  • Spillway base slabs have ineffective ground anchors to percent lateral and vertical movement
  • Builder didn't excavate native soils and incompetent rocks during concrete construction
  • Lack of 2-way steel reinforcement
  • Ineffective repairs were made to cracks and joint displacements to prevent water damage
  • Large trees were allowed to grow adjacent to the spillway, causing tree roots to damage base slabs and drainage pipes.

The 78-page report goes into deep detail citing what led to an almost catastrophic flooding event in late January to February.

If you are a fan of the "How It's Made" show, this report is for you. Scroll through the photos and charts to see just how close to catastrophe residents near the Oroville Dam came.