The Federal Energy Regulatory Commission (FECR) forensic audit of the Oroville Dam Spillway crisis project found that failures were due to inadequate California Department of Water Resources (DWR) maintenance, repair of cracks, thin concrete slabs, poor drainage, and use of weathered rock.
FERC issued a mandatory forensic audit demand letter to Acting Director California Department of Water Resources William Croyle on February 21, during the height of the Oroville Dam crisis, with 200,000 people evacuated and local engineers worrying that America’s tallest dam was on the verge of collapsing.
The State of California officially named the six-member independent engineering review team to develop a plan of action for the forensic analysis, performing field investigations and review project operations, “before, during and after the event.” But in a sign of how little confidence FERC had in California’s competence and honesty, the U.S. Director of the Division of Dam Safety and Inspections, David E. Capka, specifically “suggested” all six members of the forensic audit team.
In its first preliminary reports, the “Oroville Dam Spillway Incident Forensic Investigation Team” found 24 direct possible causes for the main spillway failure. The audit team expects to find additional factors as the investigation proceeds towards a final report in late 2017.
The forensic audit also confirmed Breitbart News’ earlier reporting that Oroville Dam’s spillway was anchored with deteriorating weathered “incompetent” rock, rather than “fresh rock” granite that could last 1,000 years. Due to prior air exposure, which causes chemical decomposition of rock over time, such weathered (old) rock apparently crumbled under pressure from spillway water flow.
Many of the factors named by the forensic audit involved the California Department of Water Resources’ (DWR) lack of management, and insufficient maintenance issues.
The State of California is believed to have spent $100 million each month for management and construction work at the height of crisis during February and March. The Sacramento Bee reported that the Kiewit Corporation was issued a $275 million contract to repair both of Oroville Dam’s main and emergency spillways over the next two years.
DWR officials claim that Oroville Dam structures can handle the rain and snowmelt during the next water year that begins on November 1.
But Breitbart News began warning in early March that the National Weather Service’s observations for the weather oscillations indicated a high probability of an El Niño weather pattern drenching California again next year.
In addition, the DWR website still predicts that rising temperatures will cause Sierra snowpack “to experience a 48-65 percent loss from the historical April 1st average. This loss of snowpack means less water will be available for Californians to use.” It also means more potential trouble for the Oroville Dam.