The Teton Dam

The Teton Dam was an earthen dam in the western United States, on the Teton River in eastern Idho. It was built by the Bureau of Reclamation, one of the eight federal agencies authorized to construct dams. Located between Fremont and Madison counties, it suffered a catastrophic failure on June 5, 1976, as it was filling for the first time.The collapse of Teton Dam resulted in eleven deaths, and killed 16,000 livestock. The dam cost about $100 million to build and the federal government paid over $300 million in claims related to its failure. Total damage estimates have ranged up to $2 billon, and the dam was not rebuilt.

An investigation of the area by geologists of the U.S. Geologic Survey indicated that it was seismically active; five earthquakes had occured within 30 miles of the dam site in the previous five years, two of which had been of significant magnitude. The dam site was composed of materials which are considered unsuitable for dam construction because of their high permeability.

In1973 when the dam was only half built, but almost $5 million had already been spent on the project, large open fissures were encountered during excavation of the keyway trench. The largest fissures were actually caves. One of them was 11 feet wide and 100 feet long. Another one was 9 feet wide in places and 190 feet long. Later, the report of a committee of the House of Representatives, which investigated the dams collapse, felt that the discovery of the caves should have been sufficent for the Bureau of Reclamation to kill the project.



* Which supports and barriers were in play?

* What were the dynamics?

* Who, or what, won the Tug-of-War?

* Discuss the outcome with your friends and family.

* Use Post #4 as a reference for the dynamics, and the relationships, between supports and barriers.