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38-525: The dam presently has a nameplate capacity of 185.25 megawatts , divided among 5 generating units (which in turn are divided between the Western and Eastern grids). Three units in powerhouse number one, completed in 1951, have a capacity of 105 MW. Completed in 1961, the two remaining generating units in powerhouse number 2, have a nameplate capacity of 80 MW. The lake has a maximum operating pool elevation of 2,250 feet (686 m) above mean sea level and

76-402: A berm (or berme) was a level space between a parapet or defensive wall and an adjacent steep-walled ditch or moat . It was intended to reduce soil pressure on the walls of the excavated part to prevent its collapse. It also meant that debris dislodged from fortifications would not fall into (and fill) a ditch or moat . In the trench warfare of World War I , the name was applied to

114-399: A berm is a raised ridge of pebbles or sand found at high tide or storm tide marks on a beach . In snow removal, a berm or windrow refers to the linear accumulation of snow cast aside by a plow . Earth berms are used above particle accelerator tunnels to provide shielding from radiation. In open-pit mining , a berm refers to dirt and rock piled alongside a haulage road or along

152-418: A normal operating pool elevation of 2,246 feet (685 m) above mean sea level. The lake level fluctuates over time based on a number of factors. During the first week of February 2007, the reservoir set a record low elevation of 2,197 feet (670 m) above mean sea level, nearly 12 feet (3.7 m) lower than the previous record low set in 1991. In June 2011, in response to the 2011 Missouri River Floods ,

190-479: A road is also called a berm and in New Zealand the word describes a publicly owned grassed nature strip sometimes planted with trees alongside urban roads (usually called a verge). [1] In snowboard cross , a berm is a wall of snow built up in a corner. In mountain biking , a berm is a banked turn formed by soil, commonly dug from the track, being deposited on the outer rim of the turn. In coastal systems,

228-529: A similar feature at the lip of a trench , which served mainly as an elbow-rest for riflemen . In modern military engineering, a berm is the earthen or sod wall or parapet, especially a low earthen wall adjacent to a ditch. The digging of the ditch (often by a bulldozer or military engineering vehicle ) can provide the soil from which the berm is constructed. Walls constructed in this manner are an obstacle to vehicles , including most armoured fighting vehicles but are easily crossed by infantry . Because of

266-423: A thick (approximately 1,000 feet (300 m)) deposit of Bear Paw shale . This shale is classified as a firm shale and contains thin (<1 to 6  in (2.5 to 15.2  cm ) layers of bentonite . The topmost layer of soft clay was removed from the alluvium in order to found the dam on the stable sandy deposits beneath, at an elevation of approximately 2,050 feet (620 m). The remaining deposits consisted of

304-527: A total combined water storage capacity of approximately 73,129,000 acre⋅ft (90.203 km) and approximately 1,111,884 acres (449,963 ha) of water surface area. The site chosen was on a stretch of the Missouri River flowing from south to north. The river bed at the site consisted of approximately 160 feet (49  m ) of alluvial deposits , varying from coarse, pervious sands and gravels to impermeable clays . Beneath these deposits lay

342-483: Is a level space, shelf, or raised barrier (usually made of compacted soil ) separating areas in a vertical way, especially partway up a long slope. It can serve as a terrace road, track, path, a fortification line , a border / separation barrier for navigation, good drainage, industry, or other purposes. The word is from Middle Dutch and came into usage in English via French. In medieval military engineering ,

380-511: Is the berm proposed for Vermont Yankee nuclear power plant in Vermont. At Baylor Ballpark , a baseball stadium on the campus of Baylor University , a berm is constructed down the right field line. The berm replaces bleachers, and general admission tickets are sold for fans who wish to sit on the grass or watch the game from the top of the hill. Berms are also used as a method of environmental spill containment and liquid spill control. Bunding

418-510: Is the construction of a secondary impermeable barrier around and beneath storage or processing plant, sufficient to contain the plant's volume after a spill. This is often achieved on large sites by surrounding the plant with a berm. The US Environmental Protection Agency (EPA) requires that oils and fuels stored over certain volume levels be placed in secondary spill containment. Berms for spill containment are typically manufactured from polyvinyl chloride (PVC) or geomembrane fabric that provide

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456-758: The Fort Peck Dam , by Montana author Lois Lonnquist, published in 2006, is an overall history of the Fort Peck dam and spillway construction. Built by the Army Corps of Engineers, PWA Project #30 provided thousands of jobs during the Great Depression. The book includes the history of the boomtowns that sprang up in the area, and the "project people" who lived and worked at Fort Peck during the "dam days." M.R. Montgomery , Personal History, "Impalpable Dust," The New Yorker , March 27, 1989, p. 94

494-464: The adverse effects of running water on exposed topsoil . Following the 2010 Deepwater Horizon oil spill in the Gulf of Mexico, the construction of berms designed to prevent oil from reaching the fragile Louisiana wetlands (which would result in massive erosion) was proposed early on, and was officially approved by the federal government in mid-June, 2010, after numerous failures to stop and contain

532-407: The alluvial materials mentioned above. These deposits had many interconnecting layers of coarse sands and gravels, necessitating the installation of a steel sheet pile wall down to the firm shale, from the left to the right abutment . As designed, the dam extends to an elevation of 2,275 feet (693 m), for a total height of 225 feet (69 m) from the cleared river bed and has a length from

570-475: The breach that was created in the shell. Portions of the core in the still-stable portion of the dam continued to slump into the hole created by the loss of the slide mass. One construction supervisor was backing his car away from the advancing scarp to the west along the beach to avoid the slumping and noted that the small scarp in the core was advancing to the west at a speed equal to his own (approximately 10 mph (16 km/h)). A pump barge moored near

608-410: The crest in the upstream embankment. As the settlement of the pool got larger, portions of the shell began to slide backwards into the core pool area and the majority of the upstream shell began to move into the reservoir, translating south and rotating slightly about the east abutment. The west end of the slide mass broke away from the dam near station 27+00 and the core pool water rapidly poured out of

646-409: The dam at the east abutment was swamped by the slide and was lost along with several tractors, loadmasters, and draglines on the slope. Of the 134 men working in the area at the time, 34 were carried into the sliding material. Of these 34, eight were unable to be rescued and lost their lives. Of the eight men, only two bodies were ever recovered, leaving six men permanently entombed in the structure. In

684-611: The dam was releasing almost 66,000 cubic feet per second (1,900 m/s), which greatly exceeded its previous record release of 35,000 cu ft/s (990 m/s) set in 1975. Fort Peck was a major project of the Public Works Administration , part of the New Deal . Construction of Fort Peck Dam started in 1933, and at its peak in July 1936 employed 10,546 workers. The dam, named for a 19th-century trading post,

722-406: The danger of the core pool overtopping or bursting the shell became greater because the beaches became narrower. For this reason, an extensive alarm system was implemented along the narrower upstream shell. This alarm system could immediately shut off the dredge pumps if a shell breach was detected. Part of this alarm system involved monitoring the elevations of the core pool and the pipelines carrying

760-400: The dredged fill. On the morning of September 22, 1938, an inspection by the engineer in charge of construction revealed that the elevation of the pipeline relative to the core pool near station 15+10 (see attached overhead photo) was only 2.5 feet (0.76 m) when it should have been 4.5 feet (1.4 m). A survey crew was dispatched immediately to determine if the fill on which the pipeline

798-441: The ease of construction , such walls can be made hundreds or thousands of kilometres long. A prominent example of such a berm is the 2,700 km (1,700 mi) Moroccan Western Sahara Wall . Berms are also used to control soil erosion and sedimentation by reducing the rate of surface runoff . The berms either reduce the velocity of the water , or direct water to areas that are not susceptible to erosion, thereby reducing

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836-426: The edge of a dump point. Intended as a safety measure, they are commonly required by government organizations to be at least half as tall as the wheels of the largest mining machine on-site. Physical security systems employ berms to exclude hostile vehicles and slow attackers on foot (similar to the military application without the trench). Security berms are common around military and nuclear facilities. An example

874-426: The fines were carried downhill toward what would eventually become the core of the dam. Samples were taken from all zones regularly to ensure that the material had the gradation and consolidation characteristics specified by the design. This process proceeded until elevation of the fill reached approximately 2,250 feet (690 m), while the reservoir was at an elevation of 2,117.5 feet (645.4 m). At this point,

912-410: The left to the right abutment of approximately 10,500 feet (3,200 m). The upstream face was designed with an average slope of one vertical on four horizontal and included three horizontal shelves built into the slope. A flatter (1 on 7.5) berm was to be placed between stations 30+00 and 75+00 (approximately the center half of the length of the dam). Since the construction method of hydraulic fill

950-491: The low permeability of the surrounding shale. This resulted in a low effective stress in the bentonite and a very low shear strength . According to the Billings Gazette , the dam was damaged by "record-high runoff and flooding in 2011." As of March 2013, "more than $ 42.9 million in repairs to Fort Peck Dam have been approved by the U.S. Army Corps of Engineers ." Fort Peck Dam is probably best known for being

988-445: The oil leak with more advanced technologies. In coastal geography, a berm is a bank of sand or gravel ridge parallel to the shoreline and a few tens of centimetres high, created by wave action throwing material beyond the average level of the sea. Earth is piled up against exterior walls and packed, sloping down away from the house. The roof may or may not be fully earth covered, and windows/openings may occur on one or more sides of

1026-402: The shale, both weathered and unweathered indicated strengths leading to a factor of safety greater than one. Also, portions of the weathered shale were found in the slide mass, indicating that the slip surface was located somewhere in the shale, but probably at a shallow depth. The core material turned out to be much stronger than expected (having a friction angle of approximately 29 degrees) and

1064-456: The shelter. Due to the building being above ground, fewer moisture problems are associated with earth berming in comparison to underground/fully recessed construction. For general applications, a berm is a physical, stationary barrier of some kind. For example, in highway construction, a berm is a noise barrier constructed of earth, often landscaped , running along a highway to protect adjacent land users from noise pollution . The shoulder of

1102-540: The story of the fictional Duff family and their various roles in the mammoth dam project, and in the process describes the working conditions and way of life of the thousands of workers hired to construct the Fort Peck Dam, many of them homesteaders from upriver farms destined to disappear under the waters of the newly formed Fort Peck Lake. The Fort Peck Dam is also featured in Ivan Doig ’s novel, The Bartender’s Tale . Fifty Cents an Hour: The Builders and Boomtowns of

1140-661: The subject of a photograph of the spillway taken by Margaret Bourke-White while still under construction that was the cover photo of the first issue of Life magazine on November 23, 1936. Later, the photograph by Bourke-White was used on a United States postage stamp in the "Celebrate the Century" series. The dam is also center-stage in Bucking the Sun , by the Montana-born writer Ivan Doig , published in 1996. The novel tells

1178-453: The testing and analysis done by the Corps of Engineers and others to determine the cause of the slide, several modes of failure were considered. These were: movement along a weak zone in the shale in the abutment, movement along the shale surface, bursting of the shell due to excessive core pressure , and temporary liquefaction of the shell or foundation sand. Extensive laboratory testing of

Fort Peck Dam - Misplaced Pages Continue

1216-649: The workers. Among these were Wheeler and McCone City as well as more than a dozen others. Many of the homes were later moved to farms and towns around Montana. Fort Peck Dam is one of six Missouri River Main stem dams operated by the U.S. Army Corps of Engineers, Omaha District . The dams downstream of Fort Peck Dam are: Garrison Dam (near Riverdale, North Dakota ), Oahe Dam (near Pierre, South Dakota ), Big Bend Dam (near Fort Thompson, South Dakota ), Fort Randall Dam (near Pickstown, South Dakota ), and Gavins Point Dam (near Yankton, South Dakota ). These six mainstem dams impound these Missouri River reservoirs with

1254-409: Was carried out into the slide nearly in a solid mass, making it unlikely that the core was the weak point in the slide. Laboratory testing was done on the shell material and the foundation sand and it was determined that both materials were denser than the critical state for liquefaction. There was no evidence of ground vibration, seismic or otherwise. Some liquefaction may have occurred after the sliding

1292-491: Was chosen, four electric dredges were built. Because of the distance of the site from the nearest shoreline, a shipyard was started on the site, affectionately dubbed "The Fort Peck Navy" and "The Biggest Shipyard in Montana" by the workers. These dredges would pump material from nearby borrow pits to the dam site where it was discharged by pipes along the outside edges of the fill. The coarser material settled out quickly, while

1330-526: Was completed in 1940, and began generating electricity in July 1943. The town of Fort Peck, Montana , "the government town," was built for Army Corps of Engineers personnel and men in "positions of responsibility" and their families during the dam's construction. Many of the facilities that supported the dam's workers are still used today, such as the recreation center and the Fort Peck Theater . In addition to Fort Peck, other towns sprang up to house

1368-495: Was founded was settling or if the pipeline footing itself was settling. Preliminary measurement showed that the pipeline was closer to the pool than expected from station 15+00 to station 17+00. A meeting with the district engineer and supervisory personnel was scheduled for 1:15 p.m. near the location in question. At approximately 1:15 p.m. the core pool near station 15+00 began to settle slowly. As its rate of settlement increased, cracks appeared 30 feet (9.1 m) below

1406-456: Was initiated, but it was unlikely that it caused the slide. The major weak point in the dam seemed to be the bentonite seams in the Bear Paw shale. Very high water pressures were reported at some points in the shale during the construction. This was likely caused by consolidation due to the overburden of the fill being placed for the dam. The excess pore pressures could not be relieved due to

1444-614: Was written by the son of an engineer who worked at the dam during its construction. After his father's death, the author researched the dam's construction and his father's role in it. Nameplate capacity Too Many Requests If you report this error to the Wikimedia System Administrators, please include the details below. Request from 172.68.168.226 via cp1108 cp1108, Varnish XID 217247913 Upstream caches: cp1108 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 07:56:20 GMT Berm A berm

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