The spillway problems that occurred at the Oroville Dam in February may be part of more systemic issues in the dam industry, says Stanford dam expert Martin McCann, Jr.
ON MAY 3, California’s Department of Water Resources (DWR) released the fourth report by an independent board of consultants examining what went wrong during the Oroville Dam emergency in February and outlining the reconstruction of its damaged spillways.
In February, a gaping hole formed in the Oroville Dam spillway as the state released excess water from the reservoir in anticipation of more rain. After an earthen emergency spillway also eroded away, authorities evacuated 188,000 people from the surrounding area, out of fear of an uncontrolled release from the dam.
Now the state is tasked with repairing the damaged spillways. Those repairs are not anticipated to be completed by the beginning of the next rainy season in October. Meanwhile, California residents and authorities have lambasted the state for its apparent secrecy regarding the spillway failure and the repairs. DWR did not initially release the consultants’ reports, citing security concerns – a move that caused public outcry. The reports were eventually released, but only redacted versions.
To get a better idea of what went wrong at Oroville and what can be learned from it, Water Deeply talked with Martin McCann, Jr., the director of the National Performance of Dams Project and an adjunct professor of civil and environmental engineering at Stanford University. McCann said that he couldn’t speak to claims of secrecy around the reports, but that Oroville did highlight major systemic issues in the dam profession, and they can learn from it.
Water Deeply: How do you and others in your field see this incident? Was this something that was unfortunate but bound to happen when you have a large structure in a geologically active state, or are professionals really looking at it as something that really should have been caught?
Martin McCann, Jr.: I am not one of those who would comment on the details. There is a forensics team working on it – they got started after the board got started, and I expect that they will pretty much get to the bottom of things. So my attitude on all that is, let them do their work, let them get their findings out there and let it be vetted by the profession once they’re done.
That being said, there are people of a certain view – certainly myself would fall into the group, whether it is a minority view or not, I don’t know, I suspect it might be. That view would be that there is something going on here within the dam engineering and safety profession that this event, which is only one of many, does have some unique features to it from an organizational, regulatory, structure perspective. Features that say, you know what, we really need to look in the mirror and ask ourselves some hard questions about everything from the day-to-day business of engineering dam safety, to the hierarchy of how we are managing these assets and the regulatory way of doing business as it is currently crafted. There are some hard questions that I think somebody needs to be willing to ask.
Water Deeply: Can you be more specific on what those questions are?
McCann: Well, I can give you some examples. The business of how we do inspections – are we really doing a good job? I mean, that is kind of a mundane, stupid question, in many ways – I read right after the event some so-called-expert said we should be inspecting these dams every year. Really? We are inspecting them every year. And in this particular case with Oroville we had two agencies and an owner inspecting them every year. That’s the problem – that we were actually inspecting them and not finding these things.
We rely greatly on the value of those inspections as a metric each year to tell us there is something going on, there is something changing. And, if every time the answer is, it all looks pretty good, and then you have an Oroville, something is wrong.
We talk about lessons learned, but the reality is the industry does not gather the data, does not analyze the data, does not truly identify the lessons, and truly does not, in a formal way, translate that into learned practices so that those lessons are truly learned. Because spillways getting ripped apart is not new. This has happened before, so there is nothing particularly unique about Oroville, in that very general sense.
Water Deeply: Why does the industry not gather and analyze the data?
McCann: You could point to a lot of things. Embarrassment – if you’re collecting data on events of unsatisfactory performance, which would include failures, you’re admitting failure. Post 9/11 there is a security-related element. I think it is just a cloak to hide behind, to some degree. We have tried to make this happen. We have even paid people to provide us data; it still doesn’t work.
At the end of the day a lot of these things take time and money and thought to make them happen, money being the big one. And the dam industry, by and large, typically does not want to spend money. Which translates more broadly into, I think that they are undervaluing the asset, and the value of the asset to society. Everybody needs water, and power, and at least some of that is going to come from dams. So we don’t invest in research, we don’t invest in improved technologies, we don’t invest in improved practices and we don’t invest in training enough people to use the practices that we have.
Water Deeply: How do we move forward?
McCann: Taking this episode as an example, I think that this is an outstanding opportunity, meaning nobody got killed. The dam did not fail, the spillway did not fail in the sense of an uncontrolled release of the reservoir. A lot of things worked – maybe by design, maybe not so much, but a lot of things worked. So, let’s not applaud, but let’s take it for what it is, which is the opportunity to meaningfully reflect on things.
Water Deeply: Do you get the feeling that the dam industry is paying more attention to Oroville than to incidents in the past?
McCann: If I had to say, then yeah, kinda, I think. Partly because of the social end of things and the media end of things. People are probably talking about this more than some others, and rightfully so. But, whether that talk is going to translate into anything meaningful – that is the real litmus test here. And that of course remains to be seen.
Water Deeply: In the second memo from the consultants, they state that there needs to be good, ongoing communication between the engineering geologists in the field and the design engineers in the office. Have you found that information can get lost between these important groups?
McCann: Interdisciplinary communication, and even within discipline communication such as engineers – there’s all kinds of engineers – has been a problem in dam engineering, where that communication is not always the best. The best example of that is the Teton Dam failure in 1976. That was an organizational failure, and one of the issues was, the engineers on site, the construction manager types, they hated the designers back in Denver, and probably vice-versa. That was the epitome of an organizational failure. We can’t let that happen, but it did and so now we don’t have a Teton Dam today.
Water Deeply: How do you get those two groups to communicate better?
McCann: It’s a good question. It’s partially an art form, because one of the things that is exceptionally important is organizational sociology. How do you get people to work together? That’s not engineering. You have to have strong management that can say “certain things are going to happen around here” and they follow through on it.
Water Deeply: The report also notes that the dam geologists need to continue developing site engineering geologic models. Is there a reason to not update them, and is this common practice?
McCann: It is rather fundamental in a constructed facility, particularly a critical piece of infrastructure like Oroville, that a detailed, complete, accurate characterization of the site be prepared. That can take a lot of work, in that there might be multiple pieces of evidence out there, there might be new evidence that you are going to have to gather, whether it is taking borings or whatever. That, frankly, may not have happened well, or not well enough, by the time the project was constructed. So, what [the consultants] might be saying is “this really never happened particularly well, if at all, and you really need a complete characterization of the site.”
Now, having said that, even if they did a good job at the time that the original site was investigated, new technologies might be able to give us a clearer, more complete picture of the geology, and they also might be saying “let’s get it up to date.”
This interview has been edited for length and clarity.
Article by: Ian Evans
Published: May 9, 2017 by Water Deeply
Read original here.