Flood Risk

Protecting Dam Breach Inundation Zones

Dam failures are a ‘low probability but high consequence’ event best addressed by preparation and maintenance.
By: | February 28, 2017 • 7 min read

After a five-year drought, the rains finally returned to California this winter. Lake Oroville, which was formed in 1967 at the foot of the Sierra Mountains by the nation’s tallest dam, began to refill.

An atmospheric river, colloquially known as a “Pineapple Express,” continued dropping water at such a pace that it replenished the reservoir and then some. The swollen lake forced the excess water onto an emergency spillway alongside the Oroville Dam for the first time in half a century.

The spillway cement crumbled and sent a cascade of water down the mountainside. Engineers feared the erosion compromised not only the spillway but also the 770-foot-tall earthen dam.

An emergency evacuation was hastily ordered and nearly 190,000 residents were forced to flee their homes. Traffic clogged roads. Fortunately, no life was lost and water levels eventually receded.

“There has to be a more robust conversation around flood.” — John Dickson president, NFS Edge Insurance Agency

For many, this crisis is a wake-up call for renewed assessment of the aging infrastructure of the U.S. dam system and the emergency response plans drawn to prevent loss of life in the event of a failure.

Dams Exceeding Effective Dates

Nearly all of the 700 dams managed by U.S. Army Corps of Engineers are more than 30 years old. More than half have reached or exceeded the 50-year service lives for which they were designed. Oroville Dam turns 50 next year.

Tim McCarty, risk control manager, Trident Public Risk Solutions

Tim McCarty is a risk control manager at Trident Public Risk Solutions, which insures a wide range of municipalities including those in close proximity to a dam. His statistics on the aging dam system in the U.S. are even more alarming.

“The average age of our dams nationwide is 56 years,” he says. “And, the average age of a failed dam is 62 years.

“So we’re kind of reaching that point where we’re starting to have some very old infrastructure and if it’s not properly maintained we may see repeats of this type of an incidence,” McCarty said.

The Federal Emergency Management Agency says dam failures are a “low probability but high consequence” event.

Since they rarely occur, many people who live downstream in “dam breach inundation zones” are completely unaware of the potential hazard. But they are, in fact, at the mercy of the dam’s ongoing health.

“The only time the concept is front and center is when water is rushing over the dam,” said John Dickson, president of NFS Edge Insurance Agency.

“I worry constantly that that’s a total disservice to the American people. We need to have the conversation when the sun is shining.”

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Dams are a vital part of the U.S. infrastructure. They provide flood protection, water supply, hydropower, irrigation and recreation. But all it takes is one busy muskrat to compromise the integrity and cause a breach.

The operators of the Oroville Dam were advised in 2005 to shore up the spillway with concrete. For a dozen years, the expensive recommendation was tabled. The reasoning was the emergency spillway was never used because the lake water never rose high enough.

“With a dam breach, when it fails, it fails quickly, the water comes out quickly and there’s a limited amount of time.” — Dr. Louis Gritzo, vice president and manager of research, FM Global.

But when it finally did, the emergency response — mass evacuations and helicopters conducting air drops of dirt and boulders to fortify the dam —averted a catastrophe.  But it also was an expense way beyond the cost of maintenance.

Perhaps most alarming, not all people received the emergency notification when the evacuation was called, according to the Associated Press.

Dams Fail Quickly

Every four years, the American Society of Civil Engineers issues a “Report Card for America’s Infrastructure.” Bridges, roads, tunnel systems are evaluated on capacity, condition, funding, future need, operation and maintenance, public safety, resilience and innovation.

Dams received a “D” grade in the 2013 report. The next report is due March 9, and there is no expectation for a major shift in that grade. The Army Corps of Engineers estimated it would currently take $24 billion to fix all dams that need repairs.

State agencies regulate most of the nation’s 84,000 dams. Unlike bridges and roads, the U.S. government may inspect the dams but they don’t maintain most of them. More than 65 percent are privately owned and those owners may lack the money needed for adequate maintenance.

Louis Gritzo, vice president and manager of research, FM Global

Experts say dam owners need to know how their structures are aging and prepare for the repairs that need to be done. Develop a timeline for a replacement and how to respond if the dam fails.

“We’re chasing an aging population,” said Louis Gritzo, vice president and manager of research with FM Global.

It is most important to conduct regular inspections and deal with what seems to be minor issues immediately.

“Many people just think you build a dam and it’s just there and fades into the background,” McCarty said.

“But it really is an active system that has to be maintained just like a road or a bridge.”

Gritzo said he discusses with clients opportunities to retrofit facilities and fill in the weak spots. More often than not, an engineer looks at an aging structure and weighs when it is best for a new build. The cost of that is often too challenging, Gritzo said.

Unlike a river flooding over its banks, a dam breach may occur with little to no warning. For that reason, an emergency response plan is needed to lay out how much time is required to get mitigation efforts in place and who is responsible for completing each task.

Conduct Hazard Assessments

“With a dam breach, when it fails, it fails quickly, the water comes out quickly and there’s a limited amount of time,” said Gritzo.

Risk managers need to conduct a very good hazard assessment in the event one of these dams has a catastrophic failure. FM Global uses tools such as complex computer models to calculate different breach scenarios and determines where the water might go and how much flooding might occur when it gets there.

As of 2015, a quarter of dams designated “high hazard” don’t have an EAP.

The insurer works with clients to decide if that amount of water is something they can protect a facility against, or if it’s too large.

“If it’s a meter of water or less you can protect against it,” Gritzo said. “That’s an easy cut-off point.”

More than a meter of water and there’s much fewer protection measures available.

The risk manager that is associated with the facility needs to know the risk exposure, how to react and who to contact in an emergency.

As of 2012, there were 13,991 dams classified as “high hazard,” up 3,000 from a decade earlier.

When a dam is designated a “high hazard,” it means there’s a potential for loss of life if it fails. All high hazard dams require an emergency action plan (EAP). Dams with a “low hazard” or “significant hazard” may have a low expectation for loss of life but still carry potential for damage to surrounding terrain, roads or buildings.

As of 2015, a quarter of dams designated “high hazard” don’t have an EAP. Sometimes, the owners don’t even know they are labeled high hazard, McCarty said.

Risk managers should contact the authority or municipality that creates the EAP to start an ongoing communication and organize emergency drills.

“The time to be swapping business cards and introducing yourself is not when there’s an emergency,” Gritzo said.

John Dickson president, NFS Edge Insurance Agency

McCarty periodically reviews the state assessments of dams in his clients’ communities to try to ascertain the condition of the dams and what kind of ongoing maintenance has been required. He also checks to make sure each community has an EAP in place should something occur.

“Our clients are doing a great job with it, but we know that there are a lot of dams that aren’t getting the attention they need,” McCarty said.

“There has to be a more robust conversation around flood,” said Dickson of NFS Edge.

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“The way we do that is not responding in the face of imminent disaster but having the conversation when the levee is not about to be breached or the spillway is not being activated because the dam is at historic highs.”

Municipal leaders should prepare to address the ongoing maintenance that is needed, the EAP they have in place and the responsibilities that go along with having a dam, McCarty said.

“We’ve had an incident here that has heightened our awareness. Those things tend to tail off as time passes,” McCarty said.

“We really need to keep this in our collective memories otherwise we’ll see more and more of these incidents occur.”

Juliann Walsh is a staff writer at Risk & Insurance. She can be reached at [email protected]

More from Risk & Insurance

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Risk Management

The Profession

After 20 years in the business, Navy Pier’s Director of Risk Management values her relationships in the industry more than ever.
By: | June 1, 2017 • 4 min read

R&I: What was your first job?

Working at Dominick’s Finer Foods bagging groceries. Shortly after I was hired, I was promoted to [cashier] and then to a management position. It taught me great responsibility and it helped me develop the leadership skills I still carry today.

R&I: How did you come to work in risk management?

While working for Hyatt Regency McCormick Place Hotel, one of my responsibilities was to oversee the administration of claims. This led to a business relationship with the director of risk management of the organization who actually owned the property. Ultimately, a position became available in her department and the rest is history.

R&I: What is the risk management community doing right?

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The risk management community is doing a phenomenal job in professional development and creating great opportunities for risk managers to network. The development of relationships in this industry is vitally important and by providing opportunities for risk managers to come together and speak about their experiences and challenges is what enables many of us to be able to do our jobs even more effectively.

R&I: What could the risk management community be doing a better job of?

Attracting, educating and retaining young talent. There is this preconceived notion that the insurance industry and risk management are boring and there could be nothing further from the truth.

R&I: What’s been the biggest change in the risk management and insurance industry since you’ve been in it?

In my 20 years in the industry, the biggest change in risk management and the insurance industry are the various types of risk we look to insure against. Many risks that exist today were not even on our radar 20 years ago.

Gina Kirchner, director of risk management, Navy Pier Inc.

R&I: What insurance carrier do you have the highest opinion of?

FM Global. They have been our property carrier for a great number of years and in my opinion are the best in the business.

R&I: Are you optimistic about the US economy or pessimistic and why?

I am optimistic that policies will be put in place with the new administration that will be good for the economy and business.

R&I: What emerging commercial risk most concerns you?

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The commercial risks that are of most concern to me are cyber risks, business interruption, and any form of a health epidemic on a global scale. We are dealing with new exposures and new risks that we are truly not ready for.

R&I: Who is your mentor and why?

My mother has played a significant role in shaping my ideals and values. She truly instilled a very strong work ethic in me. However, there are many men and women in business who have mentored me and have had a significant impact on me and my career as well.

R&I: What have you accomplished that you are proudest of?

I am most proud of making the decision a couple of years ago to return to school and obtain my [MBA]. It took a lot of prayer, dedication and determination to accomplish this while still working a full time job, being involved in my church, studying abroad and maintaining a household.

R&I: What is your favorite book or movie?

“Heaven Is For Real” by Todd Burpo and Lynn Vincent. I loved the book and the movie.

R&I: What’s the best restaurant you’ve ever eaten at?

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A French restaurant in Paris, France named Les Noces de Jeannette Restaurant à Paris. It was the most amazing food and brings back such great memories.

R&I: What is the most unusual/interesting place you have ever visited?

Israel. My husband and I just returned a few days ago and spent time in Jerusalem, Nazareth, Jericho and Jordan. It was an absolutely amazing experience. We did everything from riding camels to taking boat rides on the Sea of Galilee to attending concerts sitting on the Temple steps. The trip was absolutely life changing.

R&I: What is the riskiest activity you ever engaged in?

Many, many years ago … I went parasailing in the Caribbean. I had a great experience and didn’t think about the risk at the time because I was young, single and free. Looking back, I don’t know that I would make the same decision today.

R&I: What about this work do you find the most fulfilling or rewarding?

I would have to say the relationships and partnerships I have developed with insurance carriers, brokers and other professionals in the industry. To have wonderful working relationships with such a vast array of talented individuals who are so knowledgeable and to have some of those relationships develop into true friendships is very rewarding.

R&I: What do your friends and family think you do?

My friends and family have a general idea that my position involves claims and insurance. However, I don’t think they fully understand the magnitude of my responsibilities and the direct impact it has on my organization, which experiences more than 9 million visitors a year.




Katie Siegel is a staff writer at Risk & Insurance®. She can be reached at [email protected]