Oroville Dam in Failure Mode

With $1.1 billion spent to rebuild the Oroville Dam emergency and main spillways you would think there would be no issues that would lead one to conclude the dam would be in failure mode.. But the obvious must be stated not the stories told by the California State Department of Water Resources but just a few simple facts.

“Piping”

As this video shows “piping” in earthen dams is a serious issue. video is provided by Association of State Dam Safety Officials (ASDSO).

“Phreatic Movement”

In this video the Association of State Dam Safety Officials (ASDSO)
explains another dangerous situation that develops in earthen dam such as at Oroville. Phreatic water movement is the movement of water through soil relative to the saturation of the soil. The saturation level of the soil in the dam or adjoining soils if not kept in check the soil in the dam will “slide”.

Where will the Oroville Dam Fail First?

We must look at the systems of the dam and determine where there are current failures.

Main Spillway

Emergency SpillWay Ogee Weir

Hyatt Power Plant

Oroville Dam Failure Begins at the 908 Foot Lake Level According to The California Department of Water Resources

Information recently released by the California Division of Water Resources indicates that
1.  Oroville Dam failures will begin at the Emergency Spillway when lake levels reach 908 feet
2.  Oroville Dam failures will begin at the Main Spillway when lake levels reach 908 feet
3.  At a 899 ft lake level it only takes ~ 6 inches of rain in 21 hours to reach the 908 foot failure point
4.  No risk assessment has been performed on the unreinforced section of Emergency Spillway
5.  The Emergency Spillway no longer has capacity to be a redundancy for the Main Spillway
6.   The Emergency Spillway can now only handle a 100K CFS flow rate (was 450K CFS)
7.   The Main Spillway can now only handle a 269K CFS flow rate (was 301K CFS)
8.   Oroville Dam can no longer survive the Maximum Possible Flood ( an 1,800 year flood)
9.   Oroville Dam can not handle the Standard Project Flood when lake levels are above 848 feet
10. Global warming will make the 1,800 year Maximum Possible Flood occur more frequently 
11. Global warming will make the 440 year Standard Project Flood occur more frequently.
12. No risk mitigation work has been done on either the Spillway Gate or Hyatt Power House
13. Down stream levee failures will occur when release rates exceed 150K CFS,

The above data assumes that Oroville Dam will function 100% as claimed by the California Division of Water Resources. 

We question the veracity of 100%  dam operations for the following reasons

1. Even after massively reinforcing the top half of the Emergency Spillway, the hillside is so unstable that the Spillway flow rates had to be dropped by ~80%
2. Oroville Dam authorities have shown an inability to problem solve real time, as proven by their 2017 decision to use the Emergency Spillway despite an obviously eroding hillside, leading to issue 3
3. Oroville Dam authorities have an inability to recognize life threatening situations until the last possible moment, as evidenced by declaring an Emergency Evacuation after continuous claims of safety just moments prior.
3. In an Orwellian maneuver, Oroville Dam renamed the Emergency Spillway to the “Auxiliary Spillway” after its use resulted in a MASSIVE EMERGENCY EVACUATION; this renaming shows they WILL place and push a false appearance of safety above actual safety.
4. News organization were complicit in renaming the Emergency Spillway to the Auxiliary Spillway
5  During the recent low flow Main Spillway usage, we noticed an anomaly possibly affecting future Hyatt Power House operations. (more to follow)
6. Insufficient live Main Spillway testing has been done despite unusually high lake levels
7. Their Risk Analysis understates risks, as all risk events treated as separate and not interrelated.

Sources:

Original 1970’s Oroville Dam Operation Manual
Oroville Spillways Media Briefing 04-02-2019
Oroville Ad Hoc Group Meeting January 10, 2019

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