Category: Dams

Morrison-Knudsen’s construction of Diamond Valley Lake’s West Dam, East Dam, and Saddle Dam represents the largest earthwork project in the history of the United States, involving over 40 million cubic yards of foundation excavation and 110 million cubic yards of embankment construction.

MK’s tireless dedication to their craft left many touting “The Diamond Valley Lake project is truly a World Class civil works project” with materials drilled, blasted, crushed, loaded, hauled, placed, and compacted at an unsurpassed rate in the dam construction industry. The rock operations literally moved the mountain of rock from the south rim of the reservoir and placed it across the valley floor to form two two-mile long dams at each end of a 4-1/2-mile valley.

Brownlee Dam is a hydroelectric earth fill embankment dam on the Snake River on the Idaho-Oregon border, in Hells Canyon (river mile 285). It impounds the Snake River in the 58-mile long Brownlee Reservoir. It is part of the Hells Canyon Project that also includes Hells Canyon Dam and Oxbow Dam, also built by Morrison Knudsen and operated by Idaho Power Company.

The dam’s powerhouse contains five generating units with a total nameplate capacity of 585.4 megawatts. Lacking passage for migrating salmon, the three Hells Canyon Project dams blocked access by anadromous salmonids to a stretch of the Snake River drainage basin from Hells Canyon Dam up to Shoshone Falls, which naturally prevents any upstream fish passage to the upper Snake River basin.

Another project that was given an accelerated construction schedule where the Company was placing 300,000 cubic yards of fill and rock per day.

Silverwood Lake was created in 1971 by the construction of the Cedar Springs Dam as a forebay on the 444-mile long California Aqueduct, consequently inundating the former town of Cedar Springs and has a capacity of 73,000 acre feet. The company employed 200 ton belly dumps that were freed up from another mammoth Morrison Knudsen dam project the WAC Bennett Dam in Northern B.C. It was an incredibly efficient use of resources and experience obtained from the earlier Canadian project.

At its peak the company had 700 pieces of equipment on the site.

Deadwood Dam is located in west-central Idaho on the Deadwood River about 25 miles above its confluence with the South Fork of the Payette River and about 90 miles above Black Canyon Diversion Dam. The dam site is located in a narrow canyon where the Deadwood River has cut into granite bedrock, approximately 53 miles northeast of Boise, Idaho, at the time the Company’s headquarters.

The dam lies on the western slope of the Sawtooth Mountains with elevations in the basin varying from 5311 feet by the dam to about 8,696 feet at Price Peak. Deadwood Reservoir is three and one half miles long and covers 3,180 acres. Deadwood Dam is a concrete-arch structure with a structural height of 165 feet and a total capacity of 154,000 acre-feet, providing a regulated flow for the powerplant at Black Canyon Diversion Dam and for irrigation in the Payette Division and Emmett Irrigation District.

The Company finished the project a year ahead of schedule and employed 1600 workers for its construction.

The Dahla Dam is the largest dam in Kandahar Province, and the second largest in Afghanistan. The dam is 34 kilometers north of Kandahar City and is operated by the Helmand and Arghandab Valley Authority.

The dam was first built between 1950 to 1952 during the reign of Zahir Shah, the last King of Afghanistan. The contractor for the project was Morrison-Knudsen Afghanistan Incorporated. Now some 60 years later the Company is back on the project rehabilitating the dam with Canadian Forces assistance and the British Army. When the project is finished it is hoped that it will double the amount of irrigated land in the Arghandab River basin.

The Company looks forward to its completion as it will eventually raise the standard of living for the people of Afghanistan.

Donnells Dam is a dam in Tuolumne County, California. The concrete arch dam was constructed in 1958, with a height of 317 feet, and a length of 750 feet at its crest. It impounds the Middle Fork of the Stanislaus River for hydroelectric power, part of the Stanislaus River Tri-Dam project cooperatively owned by the Oakdale Irrigation District and the South San Joaquin Irrigation District. The site is surrounded by the Stanislaus National Forest.

The reservoir it creates, Donnell Lake, has a normal water surface of 418 acres  and has a maximum capacity of 65,000 acre feet. Recreation includes fishing, hunting, boating, camping and hiking. The Company’s schedule was slashed by a third as drought conditions plagued the area and was asked to expedite the dam’s completion.

The Company met the more aggressive time frame and was awarded a Presidential Citation for its work on the project by President Eisenhower.

At the time the Hoover Dam was the largest construction project in the world only to be super-ceded by another Morrison Knudsen led project, the rebuilding of Pearl Harbor. The construction of the dam was lead by the Company along with 5 other construction partners for a much needed shot in the arm during the Depression.

Hoover Dam spans the Colorado River in Black Canyon between Arizona and Nevada, some 30 miles southeast of Las Vegas Nevada. Constructed in the 1930s, the concrete arch-gravity structure was intended to prevent flooding as well as provide much-needed irrigation and hydroelectric power to arid regions of states like California and Arizona. At 726 feet high and 1,244 feet long, Hoover Dam was one of the largest man-made structures in the world at the time of its construction, and one of the world’s largest producers of hydroelectric power.

More than 200 Morrison Knudsen engineers worked to design the dam that would be constructed in Black Canyon. It is the highest concrete arch dam in the United States, and the largest building project that the federal government had ever undertaken.

The Company employed over 6,000 people for the project.

The Itaipu Dam is a hydroelectric dam on the Paraná River located on the border between Brazil and Paraguay. The name “Itaipu” was taken from an isle that existed near the construction site. In the Guaran language, Itaipu means “the sounding stone”.

The dam is the largest operating hydroelectric facility in terms of annual energy generation, generating 98.3 TWh in 2012 and 98.6 TWh in 2013, while the annual energy generation of the Three Gorges Dam was 98.1 TWh in 2012 and 83.7 TWh in 2013. It is a binational undertaking run by Brazil and Paraguay at the Paraná River on the border section between the two countries, 9.3 mi north of the Friendship Bridge. The project ranges from Foz do Iguacu, in Brazil, and Ciudad del Este in Paraguay, in the south to Guaira and Salto del Guaira in the north.

The installed generation capacity of the plant is 14 GW, with 20 generating units providing 700 MW each with a hydraulic design head of 118 m. In 2008 the plant generated a record 94.68 TWh, supplying 90% of the electricity consumed by Paraguay and 19% of that consumed by Brazil. The total length of the dam is 7235 m. The crest elevation is 225 m. Itaipu is actually four dams joined together – from the far left, an earth fill dam, a rock fill dam, a concrete buttress main dam, and a concrete wing dam to the right. The spillway has a length of 483 m. The maximum flow of Itaipu’s fourteen segmented spillways is 62.2 thousand cubic metres per second, into three skislope formed canals. It is equivalent to 40 times the average flow of the nearby natural Iguacu Falls. The flow of two generators (700 m3/s each) is roughly equivalent to the average flow of the Iguacu Falls (1500 m3/s).

The initial studies for Amirkabir Dam took 22 years until 1956 when formal proceedings began and the dam was constructed in the period from 1957 to 1961 by Morrison Knudsen. The ecliptic concrete structure is 590 ft high, with 98 ft length on bottom and 1,280 ft on top and its watershed is 475 mi long. The average annual water inflow to its reservoir is 472 million cubic meters. The total capacity of the dam’s reservoir is 202 million cubic meters. The bottom elevation of reservoir and normal water surface elevation of reservoir are 5,069 ft and 5,280 ft respectively.

The Amir kabir Dam was built as a multi-purpose dam to provide tap water for Tehran alongside agricultural development in Karaj. It supplies the irrigation demand of over 120,000 acres of farm land near Karaj. The power plant has been connected to the national electricity network for over 46 years and has a capacity of 90 megawatts. The lake behind the dam is a touristic attraction while being a natural habitat for rainbow trout. With its sailing and water-skiing facilities, the dam is a popular weekend summer resort.

At the time of construction the Company employed 2600 people.

Dedicated on August 24, 1975, Libby Dam spans the Kootenai River 17 miles (27 km) upstream from the town of Libby, Montana. Libby Dam is 422 feet  tall and 3,055 feet  long. The reservoir behind the dam is Lake Koocanusa; it extends 90 miles upriver from the dam and has a maximum depth of about 370 feet. Forty-two miles of Lake Koocanusa are in British Columbia, Canada. Lake Koocanusa was named for the treaty that was developed between the Kootenai Indians, the Canadian government, and the U.S. government to build the Dam and form the reservoir.

It is the fourth dam constructed under the Columbia River Treaty. The Kootenai River is the third largest tributary to the Columbia River contributing almost 20% of the total water in the lower Columbia. Libby Dam holds back an average of 5,800,000 acre feet of water.

The Company employed 60% Indian Band members for the construction of the dam who contributed immeasurably to the success of the project.

Mica Dam was operational on March 29, 1973. The dam was built to a height of 801 ft above bedrock, near the first location of the village Mica Creek. At the time, the dam was one of three storage dams built by the provincial power company BC Hydro, within the description of the Columbia River Treaty. The dam operated with a 165 sq mi reservoir containing 12,000,000 acre-ft of live storage and 20,100,000 acre-ft of total storage in McNaughton Lake (later renamed Kinbasket Lake).

The underground powerhouse, begun in 1973 was built to be 177 ft high, 79 ft wide and 778 ft long. In 1976, the first two electrical generators were commissioned and in 1977 two more were completed bringing the total capacity of the powerhouse to 1,805 MW. Another two 500 MW generators are scheduled to be added and operational in 2014 and in 2015, for a total generating capacity of 2,805 MW. The Mica powerhouse delivers its power to Nicola Substation via a 500-kilovolt, 350 mi transmission line. A second power transmission line for hydroelectric power was built to the Meridian Substation near Port Moody, British Columbia.

Mica Dam was built to provide 7,000,000 acre-ft  of water storage as outlined in the Columbia River Treaty, plus another 5,000,000 acre-ft, referred to as “non-Treaty storage”.  Since 1977 BC Hydro and the Bonneville Power Administration (BPA) have made a series of long and short term agreements for using non-Treaty storage. Negotiations for a new long-term agreement began in 2011. If implemented, it would manage non-Treaty storage until 2024.

At the time it was the Company’s largest project and the largest single project in North America.

Palisades Dam is an earth-fill dam on the Snake River in Bonneville County in the U.S. state of Idaho. The dam was completed in 1957 and provides irrigation water, flood control, and recreation; it features a four-turbine hydroelectric power plant. The dam can potentially generate 176.5 MW of electricity. The resulting water impoundment, Palisades Reservoir, has a storage capacity of 1.2 million acre-feet.

The Palisades Project supplements the storage and power generation facilities of the earlier Minidoka and Michaud Flats projects, which serve irrigation interest in Idaho on the Snake River Plain, saving about 1,350,000 acre feet through the winter for use in the growing season. With 13,571,000 cubic yards of material, the dam was the largest in the USBR system at the time of its construction.

The hydroelectric complex is comprised of a 550 feet high concrete gravity dam in Little Dalles Canyon, a 380 foot high earthfill dam on the west bank of the river, and a powerhouse in the riverbed, immediately downstream of the concrete dam. Each of the dam’s 5 power units has a capacity of 460,750 kW. Individually the units have the largest capacity of any in B.C. Hydro’s system which the Company has built several for.

The concrete powerhouse is 670 feet long, 160 feet wide and 190 feet high. The reservoir created by the dam extends 80 miles back to the tailwaters of the Mica Dam. It has a surface area of 25,300 acres. Since regulated release water from Mica provides almost three-quarters of the inflow into the reservoir, the Revelstoke power plant operates as a run-of-the-river plant, with normal maximum fluctuations in the reservoir level of 4 feet.

The Company formed a joint venture to construct the dam under the name of Revelstoke Constructors Inc. and took five years to complete.

San Luis Dam is a dam that creates San Luis Reservoir, which serves as an off-stream reservoir for the California State Water Project and the Central Valley Project. It is also known as the B.F. Sisk Dam, after Bernie Sisk. The earth-fill gravity embankment dam is 305 feet  tall and was completed in 1967. It is located between Los Banos, California and Gilroy, California, United States along Pacheco Pass.

San Luis Reservoir is the largest off-stream reservoir in the United States, with a capacity of 2,041,000 acre feet. The dam is over 3½ miles long and impounds San Luis Reservoir which has a total capacity of over 2 million acre-feet. San Luis Creek is a small stream that flows through the area and it is sometimes listed as the dam’s watershed, even though it is an off-stream reservoir.

The dam is owned by the U.S. Bureau of Reclamation, but is operated by the California Department of Water Resources to store water for its State Water Project. San Luis Reservoir and O’Neill Forebay serve as the upper and lower reservoirs for the William R. Gianelli pumped storage hydroelectric plant, which began operating in 1968. The plant’s eight Francis turbines produce a combined 424 MW. The sale of peak electricity lowers the overall cost of operating the State Water Project, particularly the California Aqueduct. A short 230 kV power line heads eastward to deliver this electricity to Northern California’s electricity backbone, Path 15.

The dam was dedicated by President John F. Kennedy on August 18, 1962 when Company founder Harry Morrison met with the President.

The San Roque Dam, operates under San Roque Multipurpose Project (SRMP) is a 650 foot tall, 3500 foot long embankment dam on the Agno River. It spans the municipalities of San Manuel and San Nicolas, Pangasinan and is nearly 130 miles north of Manila. The dam impounds a reservoir with a surface area of about 10 square miles extending north into the municipality of Itogon, Benguet.

A gated spillway protects the dam from overflowing Each wet season, the run-off is stored for later release via water turbines to generate power and irrigate crops. Agno River is the third largest river in the Philippines with a total length of 140 miles and a drainage basin at the Project site of 625 square miles. The river originates in the Cordillera Mountains, initially flows from north to south, divides into several channels in the flat central plain of Luzon and meanders westerly through the provinces of Pangasinan and Tarlac before emptying into the Lingayen Gulf. The project took five years to build and employed 3500 workers at peak construction.

The Company excavated almost 50 million cubic yards of material to construct the dam

Wanapum Dam is a hydroelectric project located on the Columbia River downstream (south) from Vantage, Washington where Interstate 90 crosses the Columbia from Grant County into Kittitas County. It is owned by the Grant County Public Utility District. Its reservoir is named Lake Wanapum. The dam, and its lake, are named after the Wanapum Indians. At height of 185 feet  and a length of 8,320 feet the dam has a rated capacity of 1,040 megawatts and annually generates over 4 million megawatt-hours.The Wanapum dam was originally licensed in 1955 for a period of 50 years. Construction was initiated in 1959 with initial beneficial operation in 1963.

The Company employed 55% Indian Band members for building of the dam and at the time it was the largest construction project in the country.

The W. A. C. Bennett Dam is a massive hydroelectric dam on the Peace River in northern British Columbia. The project further solidified the Company’s reputation as the world’s premier dam builder. At 660 ft high, it is one of the world’s highest earth fill dams. Construction of the dam began in 1961 and culminated in 1968.

At the dam, the Finlay, the Parsnip and the Peace Rivers feed into Williston Lake, also referred to as Williston Reservoir. It is the third largest artificial lake in North America (after the Smallwood Reservoir and Manicouagan) as well as the largest body of fresh water in British Columbia. Williston Lake runs 250 kilometers north-south and 150 kilometers east-west.

The construction of the dam cost $750 million, making it the largest project of its kind in the province of B.C.and in Canada. The dam was named after the premier because his vision played a major role in the project initiation, development and realization; the reservoir was named after the premier’s trusted cabinet colleague Ray Williston. The Gordon M. Shrum Generation Station at the W.A.C. Bennett Dam has the capacity to generate more than 13 billion kWh annually.

At the time of its construction the powerhouse was the largest of its kind worldwide. In addition to the benefits related to the energy generated, the construction of the dam and the reservoir also provided economic opportunities for the province of British Columbia, for the newly founded state owned electric utility BC Hydro, and for the large number of workers.

The project peaked with Morrison Knudsen employing 3500 workers on the site.