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53-536: The Teton Dam was an earthen dam in the western United States, on the Teton River in eastern Idaho . It was built by the U.S. Bureau of Reclamation , one of 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 killed 11 people and 16,000 livestock. The dam cost about $ 100 million to build and

106-436: A central section or core composed of an impermeable material to stop water from seeping through the dam. The core can be of clay, concrete, or asphalt concrete . This type of dam is a good choice for sites with wide valleys. They can be built on hard rock or softer soils. For a rock-fill dam, rock-fill is blasted using explosives to break the rock. Additionally, the rock pieces may need to be crushed into smaller grades to get

159-615: A rock-fill dam is New Melones Dam in California or the Fierza Dam in Albania . A core that is growing in popularity is asphalt concrete . The majority of such dams are built with rock and/or gravel as the primary fill. Almost 100 dams of this design have now been built worldwide since the first such dam was completed in 1962. All asphalt-concrete core dams built so far have an excellent performance record. The type of asphalt used

212-562: A rock-fill dam. The frozen-core dam is a temporary earth dam occasionally used in high latitudes by circulating a coolant through pipes inside the dam to maintain a watertight region of permafrost within it. Tarbela Dam is a large dam on the Indus River in Pakistan , about 50 km (31 mi) northwest of Islamabad . Its height of 485 ft (148 m) above the river bed and 95 sq mi (250 km ) reservoir make it

265-403: A shell of locally plentiful material with a watertight clay core. Modern zoned-earth embankments employ filter and drain zones to collect and remove seep water and preserve the integrity of the downstream shell zone. An outdated method of zoned earth dam construction used a hydraulic fill to produce a watertight core. Rolled-earth dams may also employ a watertight facing or core in the manner of

318-548: Is a viscoelastic - plastic material that can adjust to the movements and deformations imposed on the embankment as a whole, and to settlement of the foundation. The flexible properties of the asphalt make such dams especially suited to earthquake regions. For the Moglicë Hydro Power Plant in Albania the Norwegian power company Statkraft built an asphalt-core rock-fill dam. Upon completion in 2018

371-410: Is a barrier that protects the foundation of a dam from seepage and can be made during initial construction or during repair. Additionally, they can be used to strengthen foundations and contain spills. A grout curtain usually consists of a row of vertically drilled holes filled with pressurized grout , a process commonly known as pressure grouting . The holes are drilled in intervals and in such

424-486: Is at hand, transport is minimized, leading to cost savings during construction. Rock-fill dams are resistant to damage from earthquakes . However, inadequate quality control during construction can lead to poor compaction and sand in the embankment which can lead to liquefaction of the rock-fill during an earthquake. Liquefaction potential can be reduced by keeping susceptible material from being saturated, and by providing adequate compaction during construction. An example of

477-487: Is composed of basalt and rhyolite, both of which are considered unsuitable for dam construction because of their high permeability . This was confirmed by long-term pump-in tests at rates of 165 to 460 US gal (620 to 1,740 L) per minute. Test cores, drilled by engineers and geologists employed by the Bureau of Reclamation, showed that the canyon rock at the dam site is highly fissured and unstable, particularly on

530-641: Is periodically reviewed for resistance to seismic activity, for internal faults, and for physical deterioration. The dam safety program identified two other dangerous dams – Fontenelle , which very nearly failed 11 years earlier, when it was filled, in a manner similar to the Teton Dam, and again in May 1985; and the Jackson Lake Dam , which would have failed during an earthquake on the nearby Teton Fault . Teton Canyon ends about six miles (10 km) below

583-525: The California Gold Rush in the 1860s when miners constructed rock-fill timber-face dams for sluice operations . The timber was later replaced by concrete as the design was applied to irrigation and power schemes. As CFRD designs grew in height during the 1960s, the fill was compacted and the slab's horizontal and vertical joints were replaced with improved vertical joints. In the last few decades, design has become popular. The tallest CFRD in

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636-474: The Usoi landslide dam leaks 35-80 cubic meters per second. Sufficiently fast seepage can dislodge a dam's component particles, which results in faster seepage, which turns into a runaway feedback loop that can destroy the dam in a piping-type failure. Seepage monitoring is therefore an essential safety consideration. gn and Construction in the U.S. Bureau of Reclamation Grout curtain A grout curtain

689-543: The 320 m long, 150 m high and 460 m wide dam is anticipated to be the world's highest of its kind. A concrete-face rock-fill dam (CFRD) is a rock-fill dam with concrete slabs on its upstream face. This design provides the concrete slab as an impervious wall to prevent leakage and also a structure without concern for uplift pressure. In addition, the CFRD design is flexible for topography, faster to construct and less costly than earth-fill dams. The CFRD concept originated during

742-705: The Snake River and some tributaries, as far downstream as the Fort Hall bottoms. Debris clean-up began immediately and took the remainder of the summer. Rebuilding of damaged property continued for several years. Within a week of the disaster, President Gerald Ford requested a $ 200 million appropriation for initial payments for damages, without assigning responsibility for Teton Dam's failure. The Bureau of Reclamation set up claims offices in Rexburg, Idaho Falls, and Blackfoot . By January 4, 1977, seven months after

795-425: The Teton Dam in 1963 and Congress passed, without opposition, an authorizing bill the following year. The planned dam was to be an earthen structure 310 feet (94 m) high and 0.6 miles (1.0 km) long, creating a reservoir 17 miles (27 km) in length. The impounded water would be used to generate hydroelectric power . An environmental impact statement was issued for the dam in 1971, but it did not raise

848-401: The abutments of the dam that allowed water to seep around and through the earth-fill dam. The permeable loess was found to be cracked. The combination of these flaws is thought to have allowed water to seep through the dam and to lead to internal erosion , called piping, that eventually caused the dam's collapse. An investigating panel had quickly identified piping as the most probable cause of

901-404: The base of the dam than at shallower water levels. Thus the stress level of the dam must be calculated in advance of building to ensure that its break level threshold is not exceeded. Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure . The erosion of the dam's material by overtopping runoff will remove masses of material whose weight holds

954-450: The cost of producing or bringing in concrete would be prohibitive. Rock -fill dams are embankments of compacted free-draining granular earth with an impervious zone. The earth used often contains a high percentage of large particles, hence the term "rock-fill". The impervious zone may be on the upstream face and made of masonry , concrete , plastic membrane, steel sheet piles, timber or other material. The impervious zone may also be inside

1007-484: The dam had failed, the bureau continued to insist that the grouting was appropriate. In December 1972, concerned about the geological conditions of the Teton River Canyon, USGS geologist David Schleicher wrote about the Teton Dam while it was still under construction, "A final point is that flooding in response to seismic or other failure of the dam—probably most likely at the time of highest water—would make

1060-434: The dam in place and against the hydraulic forces acting to move the dam. Even a small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours. The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As

1113-508: The dam questioned the project's justifications. They argued that damming a wild and scenic river would result in the destruction of its trout fishery and other wildlife habitat and "replace a unique resource with a vulgar one." The suit questioned the economic return on the investment, the bureau's compliance with the National Environmental Policy Act, and the geologic soundness of the dam's location. Concerns over

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1166-581: The dam site in the previous five years, two of which had been of significant magnitude. This information was provided to the Bureau of Reclamation in a memorandum, but the geologists' concerns were considerably watered down in the 6-month redrafting process before the USGS sent the final version of the memo to the USBR in July 1973. In 1973, when the dam was only half built, but almost $ 5 million had already been spent on

1219-491: The dam site, where the river flows onto the Snake River Plain. When the dam failed, the flood struck several communities immediately downstream, particularly Wilford at the terminus of the canyon, Sugar City , Salem, Hibbard, and Rexburg . Thousands of homes and businesses were destroyed. The small agricultural communities of Wilford and Sugar City were wiped from the river bank. Five of the 11 deaths attributed to

1272-452: The dam, although the water running through the leaks was clear and such leaks are not unexpected for an earthen dam . At the time, the reservoir was almost at capacity, with a maximum depth of 240 feet (73 m). The only structure that had been initially prepared for releasing water was the emergency outlet works , which could carry just 850 cubic feet per second (24 m/s). The main outlet works and spillway gates were not yet in service;

1325-438: The disaster, victims had filed over 4,800 claims totaling $ 194 million and the federal government had paid 3,813 of those claims worth $ 93.5 million. The claims program was originally scheduled to end in July 1978, but continued until January 1987, when the federal government had paid 7,563 claims for a total amount of $ 322 million. No plans have been made for rebuilding the Teton Dam, but its reconstruction has been discussed over

1378-417: The early 21st century. These techniques include concrete overtopping protection systems, timber cribs , sheet-piles , riprap and gabions , Reinforced Earth , minimum energy loss weirs , embankment overflow stepped spillways , and precast concrete block protection systems. All dams are prone to seepage underneath the dam, but embankment dams are prone to seepage through the dam as well; for example,

1431-405: The embankment material began to wash out. Crews with bulldozers were sent to plug the leak, but were unsuccessful. Local media appeared at the site and at 11:15, officials told the county sheriff's office to evacuate downstream residents. Work crews were forced to flee on foot as the widening gap, now larger than a swimming pool, swallowed their equipment. The operators of two bulldozers caught in

1484-420: The embankment, in which case it is referred to as a "core". In the instances where clay is used as the impervious material, the dam is referred to as a "composite" dam. To prevent internal erosion of clay into the rock fill due to seepage forces, the core is separated using a filter. Filters are specifically graded soil designed to prevent the migration of fine grain soil particles. When suitable building material

1537-413: The eroding embankment were pulled to safety with ropes. At 11:55 am MDT (UTC−17:55), the crest of the dam sagged and collapsed into the reservoir; two minutes later, the remainder of the right-bank third of the main dam wall disintegrated. Over 2,000,000 cubic feet per second (57,000 m/s) (many times the average flow rate of Niagara Falls ) of sediment-filled water emptied through the breach into

1590-426: The failure, then focused its efforts on determining how the piping started. Two mechanisms were possible. The first was the flow of water under highly erodible and unprotected fill, through joints in unsealed rock beneath the grout cap and development of an erosion tunnel. The second was "cracking caused by differential strains or hydraulic fracturing of the core material." The panel was unable to determine whether one or

1643-454: The federal government paid over $ 300 million in claims arising from its failure. Total damage estimates have ranged up to $ 2 billion, and the dam was not rebuilt. Interest in building a dam in the eastern Snake River Plain had arisen for many years to control spring runoff and provide a more constant water supply in the summer. The area had suffered a severe drought in 1961, followed by severe flooding in 1962. The Bureau of Reclamation proposed

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1696-401: The filling rate to deal with the additional spring run-off, while continuing to inspect for leaks and monitor the groundwater. A month later, though monitoring showed that groundwater was flowing a thousand times faster than had been originally anticipated, the filling rate was doubled again, to 4 feet (1.2 m) a day. On June 3 and 4, 1976, three small springs were discovered downstream of

1749-529: The flood occurred in Wilford. The similar community of Teton , on the south bank of the river, is on a modest bench and was largely spared. One Teton resident was fishing on the river at the time of the dam failure and was drowned. An elderly woman living in the city of Teton died as a result of the evacuation. An estimated 80% of existing structures were damaged in the Hibbard and Rexburg area, whose population

1802-505: The flood of February 1962 look like small potatoes. Since such a flood could be anticipated, we might consider a series of strategically placed motion-picture cameras to document the process." The dam was completed in November 1975 and filling the reservoir began at the standard rate of one foot (300 mm) a day. However, snows were heavy that winter, and five months later, the project's construction engineer requested permission to double

1855-485: The flood was effectively over, but tens of thousands of acres of land near the river were stripped of fertile topsoil. The force of the failure destroyed the lower part of the Teton River, washing away riparian zones and reducing the canyon walls. This damaged the stream's ecology and hurt the native Yellowstone cutthroat trout population. The force of the water and excessive sediment also damaged stream habitat in

1908-485: The flow of the water and continue to fracture into smaller and smaller sections of earth or rock until they disintegrate into a thick suspension of earth, rocks and water. Therefore, safety requirements for the spillway are high, and require it to be capable of containing a maximum flood stage. It is common for its specifications to be written such that it can contain at least a one-hundred-year flood. A number of embankment dam overtopping protection systems were developed in

1961-404: The gates were cordoned off by steel walls while they were being painted. On Saturday, June 5, 1976, at 7:30 am MDT , a muddy leak appeared, suggesting sediment was in the water, but engineers did not believe there was a problem. By 9:30 am, the downstream face of the dam had developed a wet spot, which began to discharge water at 20 to 30 cubic feet per second (0.57 to 0.85 m/s) and

2014-492: The ground surface beyond the right end of the dam and grout curtain. The largest fissures were actually caves . One of them was 11 feet (3.4 m) wide and 100 feet (30 m) long. Another one was 9 feet (2.7 m) wide in places and 190 ft (60 m) long. These were not grouted because they were beyond the keyway trench and beyond the area where the bureau had decided grouting was required. This necessitated using twice as much grouting as had been originally anticipated;

2067-448: The largest earth-filled dam in the world. The principal element of the project is an embankment 9,000 feet (2,700 m) long with a maximum height of 465 feet (142 m). The dam used approximately 200 million cubic yards (152.8 million cu. meters) of fill, which makes it one of the largest man-made structures in the world. Because earthen dams can be constructed from local materials, they can be cost-effective in regions where

2120-480: The lawsuit, work began in February 1972. After various motions, amended complaints, attempted injunctions, and appeals, the suit was dismissed on December 23, 1974. The eastern Snake River Plain is almost entirely underlain by basalt erupted from large shield volcanos on top of rhyolitic ash -flow tuff and ignimbrites . The tuff , a late- Cenozoic volcanic rock , is 1.9 million years old. The dam site

2173-423: The mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure. The embankment, having almost no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them, eroding and removing even more material as it passes through. In the final stages of failure, the remaining pieces of the embankment would offer almost no resistance to

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2226-492: The other mechanism occurred, or a combination: The fundamental cause of failure may be regarded as a combination of geological factors and design decisions that, taken together, permitted the failure to develop. A wide-ranging controversy ensued from the dam's collapse. According to the Bureau of Reclamation, bureau engineers assess all reclamation dams under strict criteria established by the Safety of Dams program. Each structure

2279-472: The possibility of a collapse. Lack of funding and site preparation work and questions surrounding the required environmental impact statement stalled the project. Barely 14 pages long, the statement quickly drew the ire of opponents of the project. On September 27, 1971, several environmental and conservation groups filed a lawsuit in Idaho District Court to stop the construction. Opponents of

2332-509: The project, large, open fissures were encountered during excavation of the keyway trench near the right end of the dam, about 700 ft (210 m) from the canyon wall. The two largest, near-vertical fissures trended generally east–west and extended more than 100 ft (30 m) below the bottom of the key trench. Some of the fissures were lined with calcite, and rubble filled others. Several voids, as much as 6 in (15 cm) wide, were encountered 60 to 85 ft (18 to 26 m) below

2385-480: The remaining 6 miles (10 km) of the Teton River canyon, after which the flood spread out and shallowed on the Snake River Plain . By 8:00 pm, the reservoir had completely emptied, although over two-thirds of the dam wall remained standing. Study of the dam's environment and structure placed blame for the collapse on the permeable loess soil used in the core and on fissured (cracked) rhyolite in

2438-410: The right range of size for use in an embankment dam. Earth-fill dams, also called earthen dams, rolled-earth dams or earth dams, are constructed as a simple embankment of well-compacted earth. A homogeneous rolled-earth dam is entirely constructed of one type of material but may contain a drain layer to collect seep water. A zoned-earth dam has distinct parts or zones of dissimilar material, typically

2491-455: The right side (as one faces the direction of flow). The widest fissures were determined to be 1.7 inches (4.3 cm) wide. The bureau planned to seal these fissures by injecting grout into the rock under high pressure to create a grout curtain in the rock. In addition, an investigation of the area by geologists of the U.S. Geologic Survey indicated that it was seismically active; five earthquakes had occurred within 30 miles (50 km) of

2544-661: The seismic conditions of the dam site delayed the bid process pending further review by the Department of the Interior. Pressure from Idaho's congressional delegation stopped the review, and in spite of the lawsuit, bids were taken in Idaho Falls on October 29, 1971. The $ 39 million contract was awarded in December 1971 to Morrison-Knudsen Co. of Boise , assisted by Peter Kiewit Sons Co. of Omaha, Nebraska . In spite of

2597-553: The total injected grout included 496,515 ft of Portland cement, 82,364 ft of sand, 132,000 pounds of bentonite, and 418,000 pounds of calcium chloride, injected into 118,179 linear ft of drilled holes. Later, the report of a committee of the House of Representatives , which investigated the dam's collapse, felt that the discovery of the caves should have been sufficient for the Bureau of Reclamation to doubt its ability to fill them in with grout, but this did not happen. Even after

2650-518: The town. The flood waters traveled west along the route of the Henrys Fork of the Snake River , around both sides of the Menan Buttes , damaging the community of Roberts . The city of Idaho Falls , even further down on the flood plain, had time to prepare. At the older American Falls Dam downstream, engineers increased discharge by less than 5% before the flood arrived. That dam held and

2703-504: The world is the 233 m-tall (764 ft) Shuibuya Dam in China , completed in 2008. The building of a dam and the filling of the reservoir behind it places a new weight on the floor and sides of a valley. The stress of the water increases linearly with its depth. Water also pushes against the upstream face of the dam, a nonrigid structure that under stress behaves semiplastically, and causes greater need for adjustment (flexibility) near

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2756-498: The years. Footage and interviews are featured in Catastrophe-No Safe Place (1980), hosted by Charles Bronson and Jill Ireland . Earthen dam#Earth-fill dams Embankment dams come in two types: the earth-filled dam (also called an earthen dam or terrain dam ) made of compacted earth, and the rock-filled dam . A cross-section of an embankment dam shows a shape like a bank, or hill. Most have

2809-441: Was about 10,000. The Teton River flows through the industrial, commercial, and residential districts of north Rexburg. Much of the damage in the area was done by thousands of logs dislodged from a lumber yard. Dozens of them hit a bulk gasoline-storage tank a few hundred yards away. The gasoline ignited and sent flaming slicks adrift on the racing water. The force of the logs and cut lumber and the subsequent fires practically destroyed

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