February 17, 2012
Those Who Refuse to Learn…
As the largest wholesaler of water in the country, the Bureau of Reclamation has been responsible for building various dams across the United States. The bureau now provides water for over 31 million people, and provides irrigation for one in five American farmers (1). However, in an effort to seek more and more sources of irrigation, the bureau began to choose dam sites that were less than desirable. As we read in this week’s reading of Cadillac Desert, all of the logical dam sites have already been built, leaving the Bureau to then begin damming up sites that have previously been rejected some forty years previously. As our population grows, and the sources of water diminish, the pressure on the Bureau of Reclamation to build more dam sites has increased as well. While many of these dams have turned out to be successful, disasters such as the failure of the Teton dam provide constant worry. The potential for a catastrophic disaster has only increased over time as multiple dams have been built on the same waterway. Now if one dam fails, the excess water will proceed to cause the next dam to also fail, with a domino effect capable of causing significant damage.
A map showing the locations of the 8,100+ dams in the United States
The bureau’s greatest disaster, the Teton dam, provides an interesting illustration of what can happen when bureaucracy transcends logical science to achieve an economic goal. The Teton dam was built in Northern Idaho, in order to provide irrigation to the many potato farmers in the region. It would provide irrigation to an area that already on average received 132 inches of irrigation a year, which amounts to five times the rainfall in the farmlands of Iowa. The dam’s original selling point was to provide a stable water source for these farmers, after two years of moderate drought (where ironically the crop yields were higher than normal) and a flood. While this certainly doesn’t provide sufficient reason to build a dam on a previously rejected site, everyone bought into the idea, and the construction was quickly underway. Aside from the Geologic Survey report presented to the Bureau, four regional geologists also submitted a statement that did in fact heed caution towards the safety of the dam, especially if an earthquake should arise, due to the semi-solid rhyolitic rock foundation. However, when the bureau calculated the cost and benefit analysis for building the dam, when factoring in the worst possible floods that could result without the dam; they ignored the concerns and decided to continue with construction. The project was officially finished in October of 1975, and they began to divert the river to fill the dam. Less than a year later, the excessively high water level, combined with insufficient outlets, eventually led to failure during the first filling of the reservoir. At 350 feet, this dam was the highest to ever fail, releasing billions of gallons of water. It resulted in 11 deaths, countless lost livestock, and nearly a billion dollars of damage (2).
Image of the Teton dam catastrophically failing
It turns out that the chapter title, “Those who refuse to learn…,” is increasingly appropriate because just this year the Bureau of Reclamation has completed a study to assess the rebuilding of the Teton dam. While officials say the re-build is still in the distant future, it is certainly in the conversation as a solution to Idaho’s water storage problem. The new cost of the Teton dam is estimated around $550 million, but is compared to the $10 billion Idaho economy that may be in risk without water (3). Unfortunately, this discussion of the dams in this region is still centered primarily on the economic impact, rather than the geological and environmental consequences of another large-scale project. Additionally, many geologists expressed their concerns with the selection of this site for a dam, the first time it was built. Even if they rebuild the dam in a slightly different way, it is concerning to think they may try to rebuild the dam in a geologically inadequate location. It shall be fascinating to see how this plays out in the future, as the aquifer below Idaho is currently running a 600,000 acre feet water deficit, and the Teton dam provides the largest storage area, of 200,000 acre feet of water. Hopefully, regardless of their decisions, the Bureau of Reclamation will be able to avoid disaster this time.
This post was authored by Melissa Krigbaum ’12, a double major in Economics (BA) and Environmental Studies (BA).
SOURCES
- Bureau of Reclamation website http://www.usbr.gov/main/about/
- Teton Dam Failure http://web.mst.edu/~rogersda/teton_dam/
- Years after failure, Teton Dam continues to spark debate
http://www.uvsj.com/news/years-after-failure-teton-dam-continues-to-spark-debate/article_7882fe46-c2b1-11e0-b31f-001cc4c002e0.html?mode=print - Teton Dam rebuild still option for water storage
http://www.tetonvalleynews.net/news/teton-dam-rebuild-still-option-for-water-storage/article_521f5046-a29b-11e0-85d4-001cc4c03286.html
I would agree that the conversations of dam building in the past and currently focus far too much on economic gains rather than environmental and economic loss. As Melissa states, “The new cost of the Teton dam is estimated around $550 million, but is compared to the $10 billion Idaho economy that may be in risk without water”. These numbers are huge and when first looking into the how much Idaho’s economy depends on the building of this dam, all arguments against it will be thrown out the window. That is what is wrong with a lot of individuals. Some people are just willing to face much more risk than others. We do risk-benefit analyses on projects like this, but the truth is that a lot of the time the risks are looked over completely. It is easy to believe that a new dam would never break the same way the last one did, so people are willing to gamble their property and lives on an assumption that the engineers have learned from the mistakes of the ones from the first dam. But that is the issue and Melissa says. The title is so appropriate because people act like we have learned about the mistakes behind why the dam failed in the first place and we are unable to make them again. But the fact is that the reasons behind failing dams is rarely certain and the fact that building a dam in a spot where one has already failed and that geologists 40 years ago (with outdated equipment) said was an unstable location is still being thought about today shows that nothing has been learned.
I find the picture of the dam breaking in this paper very interesting. When reading the article, it is difficult to grasp the phenomenon of the Teton Dam breaking. Seeing a picture of it makes the situation so much more real and devastating to imagine.
Also, I am very shocked to hear that the Bureau is considering reconstructing the Teton Dam. I feel that we like to think we have learned from our mistakes, especially regarding dam construction, but apparently that is not necessarily so. The underlying rock of the region could not have changed in this time, so the same issues of fissures and cracked rock will still be very relevant in the rebuilding of the dam. It can be hoped for that, if the dam reconstruction is attempted, that technology and engineering have improved to the point that the dam will be safer than it was before. Either way, however, it is a risky move and I am surprised the public in that region would be on board; it is very risky for the people living in the region for the dam to be built. However, if water supplies are short and the rebuilding of the dam would greatly increase them, then it is no wonder that it is of consideration. I hope that the officials considering this dam reconstruction have considered all the risks and other possibilities before undertaking this project.
Its amazing to look into a bureacracy and see how decisions are made. If one elected official decides he or she wants to strongly urge a particular subject, they can persuade others to jump on the band wagon. Its fascinating the power of an individual especially if they are well known within the political community. The fact that the Teton Dam was built in the first place just shows the power of political influence. There was really no urgency to even build the dam in the first place and because of the lack of proper infrastructure it failed.
With the increased awareness on the negative economic and environmental impacts of hard path structures I do not believe that the dam will be rebuilt. Especially with the increasing political power of NGO’s, I do not believe that it will be willing accepted.