California faces a triple whammy in which millions of California residents are at risk for three major dam failures. Most readers are aware that the Oroville Dam is in crisis. The latter part of this report will provide a very grim update of the condition of the Oroville and the desperate measures being employed to delay the catastrophic failure of the dam. However, a second dam, the Prado Dam, which now threatens over one million resident of Orange County is in crisis. 

CSS colleague, Alexandra Daley, sent a summation of a newspaper account, written by Ashley Ludwig, Patch Staff  which was written on May 17, 2019 at 1PM Pacific time.  

The Prado Dam is now at a high urgency risk characterization, according to the U.S. Army Corps of Engineers. Federal engineers are stating that there is a good chance for a "significant flood event. and they upgraded the dam's risk category from moderate to high urgency."

According to Federal officials, strong Pacific storms, could produce conditions that could breach the spillway of the Orange County dam. A catastrophic failure has the potential to "drown out dozens of downstream communities, from Anaheim's Disneyland to Newport Beach" according to the Army Corps of Engineers from the Los Angeles District.

Over 1.4 million people live and work below Prado Dam, with property valued at over $61 billion, including Disneyland and many high-end resorts and properties in Newport Beach.

The Dam has been near failure in the past. In 2005, a leak in the dam led to the evacuation of hundreds of thousands of people in Corona. 

Army Corps of Engineer spokesperson, Lillian Doherty told the LA Times that the spillway was a concern, but that repairs on the spillway won't begin for at least two years. The obvious question jumps off the page: What if a hundred year storm should strike the area before repairs are completed? This damaged spillway is a clear and present danger to 1.4 million residents. However, farther north, the Department of Water Resources (DWR) won't even admit the Oroville Dam spillway cannot be used 

Ominous Update On the Oroville Dam

Spillway? Did someone say spillway? At least in Orange County, the federal government has a presence. The people of Orange County should feel good about this. For months, Paul Preston and myself have saying the spillway is damaged and cannot be used to handle the spring run-offs and heavy rains. The people that have mocked our warnings owe us both an apology. In a last ditch effort to save the dam, the DWR is attempting to divert water through the power plant by utilizing something called penstocks. This will allow the Oroville Dam to generate 13,000 cubic feet per second of water with regard to the outflow of water expelled by the dam. Presently the dam cannot generate more than 10,000 cubic feet per second. This process is now needed because the spillway is damaged beyond repair. This is what Paul Preston and myself have been saying, and showing with photos published on our respective websites, and we are now seeing the proof which is employing this desperate and last ditch attempt to delay the inevitable. From the inflow/outflow numbers at the dam, we figure they have an additional three days. The day of reckoning for Oroville Dam is almost here .

The Oroville Dam is less than 10 feet from overtopping.  What happens when an earthen dam like the Prado or Oroville Dam has its water overtop the dam? Here is what Army Corps of Engineers Division Chief, Lillian Doherty says about this issue.

"Our concern right now is about the concrete slab of the spillway and how well it will perform if water were to spill over the top of the dam, We will determine whether or not it is as reliable as it should be."

 At least the residents near the Prado Dam are being considered. Doherty stated that they are working to develop outreach strategies to alert the estimated 1.4 million people who could be impacted. The people, downstream from the Oroville Dam are being lied to by the DWS. They are being told there is no danger despite the fact that it is obvious for any to see that has eyes to see.

Doherty said her agency is working with a national team of experts to develop interim and permanent risk-reduction measures at the Prado Dam, as well as public outreach strategies to alert the estimated 1.4 million people who live and work in 29 communities downstream.

One may remember that in February 2017, Butte County officials evacuated 180,000 people from the Oroville Dam area because a concrete spillway was deemed to be ineffective. As the situation at the Oroville Dam disintegrated during heavy rains, an evacuation of more than 180,000 people commenced. Had the dam collapsed, all would have been caught in the resulting flood waters and would have all perished in their cars. 

The head of the California Water Resources Department was removed after an independent probe found the failure was the result of a lax safety culture. Nothing has changed. 

That same year, the Corps of Engineers discovered that the 60-year-old Whittier Narrows Dam, about 40 miles to the west of Prado Dam, was structurally unsafe and posed a potentially catastrophic risk to more than 1 million people in working-class communities along the San Gabriel River floodplain.

 Engineers also found that the earthen structure could fail if water were to flow over its crest.

With less than 10 feet from overtopping, why isn't the Oroville Dam attracting the attention of the Army Corps of Engineers? Why is the inept DWR still in charge? The Whittier Narrows is of concern because the Army Corps of Engineers used the phrase "catastrophic risk to more than 1 million people..". This is exactly what we are looking at with regard to the Oroville Dam and nobody is saying anything. If the Oroville Dam suffers a catastrophic failure the following will happen with regard to the impact on human survival:

• A 30 foot wall of water will escape the failed Oroville Dam
• The water will be traveling at 75 mph
• It would take a minimum of 72 hours to evacuate Sacramento and Stockton
• A 20 foot wall of water would reach Sacramento within 45 minutes
• Over 1 million people lie in the path of the water 
• As with all these soon-to-be-failed dams, the spillways constitute the major reason for potential failure and we are not clearly seeing this condition at the Oroville Dam

From Agenda 21 Radio

 

Please note the enormous craines. This photo was taken on May 16, 2019. They are not holding back the water, they are checking for catastrophic failure potential. Not a word to the public, but the DWR is very worried! 

 

The Latest Outflow and Inflow Reports From the Oroville Dam

Earlier in this publication I alluded to a new mitigation strategy being employed by the DWR as they are rerouting some of the water through the power plant. They are using the penstocks to accomplish this goal. The penstocks can mitigate flood waters to a certain degree and for only a certain time. The use of the penstocks stresses the dam in other areas and is only meant to mitigate a severe crisis. By using the penstocks, the DWR is admitting that the spillway is not usable. Again, the outflow that can be generated is about 13,000 cubic feet per second. The water approaching the dam over the next several days is peaking at 17,500 inflow. Eventually the dam is going to overtop and the dam will likely fail. 

Below is a chart which shows the use of the penstocks is barely meeting the need. However, as it continues to rain and the snow begins to melt, catastrophe is likely. 

 

OROVILLE DAM (ORO)

Elevation: 900.0' · FEATHER R basin · Operator: CA Dept of Water Resources/O&M Oroville Field Division

 

Query executed Saturday at 12:17:37  

Provisional data, subject to change.
Select a sensor type for a plot of data.

Earlier

DATE / TIME PDT	RES ELE FEET	STORAGE AF	OUTFLOW CFS	INFLOW CFS	RIV REL CFS	RAIN INCHES	BAT VOL VOLTS
05/18/2019 01:00	890.92	3,396,134	11,995	13,384	9,461	44.04	13.4
05/18/2019 02:00	890.93	3,396,288	11,988	13,993	9,461	44.04	13.4
05/18/2019 03:00	890.94	3,396,442	11,875	13,578	9,487	44.04	13.4
05/18/2019 04:00	890.95	3,396,595	11,925	13,083	9,512	44.04	13.4
05/18/2019 05:00	890.95	3,396,595	11,942	11,914	9,487	44.04	13.4
05/18/2019 06:00	890.95	3,396,595	12,035	11,921	9,487	44.04	13.4
05/18/2019 07:00	890.95	3,396,595	12,009	11,927	9,512	44.04	13.4
05/18/2019 08:00	890.95	3,396,595	11,961	11,920	9,513	44.04	13.4
05/18/2019 09:00	890.95	3,396,595	12,000	11,917	9,513	44.04	13.4
05/18/2019 10:00	890.95	3,396,595	12,052	11,931	9,513	44.04	13.4
05/18/2019 11:00	890.95	3,396,595	11,927	11,942	9,513	44.04	13.4
05/18/2019 12:00	890.95	3,396,595	--	--	--	44.04	13.4

Conclusion

According to Paul Preston, some people are evacuating. However, many more are unaware of the danger. Both the federal and state governments are acting irresponsibly. Given how quickly the Oroville dam could unravel, evacuations should have already been underway. 

"A troubling theme is emerging as the Corps reviews its portfolio of large flood control systems that were built a long time ago and are now showing signs of severe stress," said Daniel Swain, a UCLA climate scientist told the LA Times. "Federal engineers are finding that these systems are not as resilient as they thought they were and that the frequency of what were regarded as once-in-a-lifetime storms is increasing significantly."