Pittsburgh-Des Moines Steel Co.

Pittsburgh-Des Moines Steel Co., commonly called Pitt-Des Moines Steel or PDM, was an American steel fabrication and engineering company whose roots went back to the Des Moines Bridge and Iron Company, established in 1892. The business was founded by William H. Jackson and Berkeley M. Moss, graduates of Iowa State College. Edward W. Crellin, who operated a small fabrication shop in Des Moines, Iowa, subsequently joined the venture. The company initially arranged for steel tanks to be fabricated by Keystone Bridge Company in Pittsburgh, while it developed a broader business supplying engineered steel structures for municipalities, utilities, transportation projects, and industrial customers. Its early product range included elevated water tanks, standpipes, waterworks equipment, bridges, structural members, and steelwork for electric plants. Steel stock was shipped from Pittsburgh to Iowa for fabrication, reflecting the company’s original geographic and commercial connection to both cities. A fabrication plant opened in Warren, Pennsylvania, in 1900. Berkeley M. Moss left the enterprise around 1905, after which the company continued expanding its manufacturing and contracting activities. The company adopted the Pittsburgh-Des Moines Steel Company name in 1916 and opened a new headquarters in Pittsburgh. It remained a partnership until incorporation in 1956. Corporate naming later changed to Pittsburgh-Des Moines Corporation in 1980 and to Pitt-Des Moines, Inc. in 1985. The company had registered the PDM trademark by 1930, and the abbreviated name was widely used in business and project references. PDM’s historical importance rests in part on the public infrastructure that it fabricated or erected. Its work included numerous steel bridges and municipal water towers, many of which were later listed on the National Register of Historic Places. The company was also the steel fabricator and erector for the Gateway Arch in St. Louis, constructed from 1963 to 1965. During the 1960s it fabricated the distinctive forked columns used in the World Trade Center complex in New York. These projects placed the company among the major American specialists in large-scale structural steel fabrication. The company experienced significant operational disruption in the late twentieth and early twenty-first centuries. In July 1993, flooding from Iowa’s Raccoon River damaged the original Des Moines site and fabrication works beyond salvage. The facility, then known as the Des Moines Heavy Bridge Division, was permanently closed and later sold. In 2001, the Chicago Bridge & Iron Company acquired the company’s principal assets and operations, while Reliance Steel & Aluminum Co. acquired its steel distribution unit. The original Pittsburgh-Des Moines corporate entity therefore ceased operating as an independent business at approximately the beginning of the 2000s, although facilities, assets, and successor operations continued under other ownership. Chicago Bridge & Iron, later known as CB&I, closed the Warren, Pennsylvania, plant in early 2009. In 2013, PDM steel plants in Eau Claire and Wausau, Wisconsin, and Palatka, Florida, were sold to Veritas Steel LLC. A later PDM-related headquarters relocation to Elk Grove, California, was reported in 2016, reflecting the continued use of the PDM name in successor or reorganized operations rather than the uninterrupted existence of the original independent company. The historic brand is consequently best understood as a defunct American steel-fabrication company whose legacy survives through landmark structures, preserved bridges and waterworks, and successor businesses.

Pittsburgh-Des Moines Steel Co. originated in 1892 as the Des Moines Bridge and Iron Company. William H. Jackson and Berkeley M. Moss, both graduates of Iowa State College, established the venture and initially contracted with Keystone Bridge Company of Pittsburgh to fabricate steel tanks. Edward W. Crellin, proprietor of a small Des Moines fabrication shop, soon joined the partnership. The business combined Pittsburgh steel supplies with Iowa fabrication capacity and began producing engineered structures for water systems, bridges, waterworks, and electric plants. The company’s early work was closely tied to the growth of municipal infrastructure in the United States. It manufactured elevated metal tanks, standpipes, bridge components, and other steel structures that could be shipped and assembled in communities across the country. A new fabrication plant opened in Warren, Pennsylvania, in 1900. Moss left the business around 1905, after the Warren facility had been established, while the company continued to develop its manufacturing and contracting network. In 1916, the enterprise adopted the Pittsburgh-Des Moines Steel Company name and opened a headquarters in Pittsburgh. The new name reflected the company’s two principal geographic associations: steel and industrial connections in Pittsburgh and its original fabrication base in Des Moines. The partnership structure lasted until 1956, when the company was incorporated. It later became Pittsburgh-Des Moines Corporation in 1980 and Pitt-Des Moines, Inc. in 1985. The company also used PDM as a registered trademark from at least 1930. Across the twentieth century, PDM became known for large-scale steel fabrication and erection. Its projects included numerous road and pedestrian bridges, elevated water tanks, water-pumping facilities, and industrial structures. Many surviving examples are listed on the National Register of Historic Places, documenting the company’s contribution to regional infrastructure and the development of American steel construction. The company’s most prominent architectural assignment was the Gateway Arch in St. Louis. From 1963 to 1965, Pittsburgh-Des Moines served as the steel fabricator and erector for the stainless-steel monument. The company also fabricated the forked columns used in the World Trade Center during the 1960s. The Des Moines works suffered a decisive setback in July 1993 when flooding from the Raccoon River destroyed the original site and fabrication works beyond salvage. The facility, then operating as the Des Moines Heavy Bridge Division, was permanently closed and later sold. This event removed the company’s historic Iowa manufacturing base and contributed to the restructuring of its operations. In 2001, Chicago Bridge & Iron Company acquired Pittsburgh-Des Moines and its principal assets. In the same year, Reliance Steel & Aluminum Co. acquired the company’s steel distribution unit. These transactions effectively ended the original company’s independent operating history, generally placed at approximately 2002, although its facilities and business activities continued through successor ownership. CB&I later closed the Warren plant in early 2009. In 2013, Veritas Steel LLC acquired former PDM plants in Eau Claire and Wausau, Wisconsin, and Palatka, Florida. Reference material also reports a PDM headquarters relocation to Elk Grove, California, in 2016, apparently reflecting a continuing or successor operation using the PDM name. The company’s legacy is therefore divided between a historical corporate identity and the physical works it produced. Historic bridges, water towers, waterworks, and major landmarks remain evidence of its engineering and fabrication role. The Gateway Arch and the former World Trade Center columns are especially prominent examples, while many smaller municipal structures illustrate the company’s long-running role in supplying durable steel infrastructure throughout the United States.

1. 2013Former PDM plants are sold to Veritas Steel

   Veritas Steel acquired former PDM facilities in Wisconsin and Florida.

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2. 2001Assets are divided among successor owners

   Chicago Bridge & Iron acquired the principal company assets, while Reliance Steel & Aluminum acquired the steel distribution unit.

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3. 1993Des Moines plant permanently closes after flooding

   The Raccoon River flood destroyed the Des Moines Heavy Bridge Division beyond salvage.

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4. 1985Corporate name shortened to Pitt-Des Moines, Inc.

   The corporation changed its name to Pitt-Des Moines, Inc.

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5. 1980Corporate name changes to Pittsburgh-Des Moines Corporation

   The company adopted the Pittsburgh-Des Moines Corporation name.

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6. 1963Gateway Arch fabrication and erection begins

   Pittsburgh-Des Moines fabricated and erected the steelwork for the Gateway Arch project, completed in 1965.

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7. 1956Partnership becomes a corporation

   After operating as a partnership for decades, the company was incorporated.

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8. 1930PDM trademark registered

   The company registered the abbreviated PDM mark, which became a commonly used identifier.

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9. 1916Company adopts the Pittsburgh-Des Moines Steel name

   The business changed its name and opened a headquarters in Pittsburgh.

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10. 1900Warren, Pennsylvania, fabrication plant opens

    The company opened a new fabrication plant in Warren, expanding beyond its original Des Moines base.

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11. 1892Des Moines Bridge and Iron Company is founded

    William H. Jackson and Berkeley M. Moss founded the original business, later joined by Edward W. Crellin.

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An engineering-led American steel fabricator serving infrastructure, municipal utilities, transportation, industrial construction, and landmark architectural projects.

• Municipal water tanks and towersWater infrastructure1892

  Water tanks, elevated towers, and standpipes were among the company’s foundational products. PDM supplied steel structures for municipal water storage and distribution systems, including numerous surviving installations in Midwestern and Southern communities. Several examples attributed to the company or its predecessor names are listed on the National Register of Historic Places.

• BridgesTransportation infrastructure1892

  Pittsburgh-Des Moines fabricated and erected steel highway, railroad, viaduct, and pedestrian bridges. Its bridge portfolio included structures in Iowa, Texas, Arkansas, Vermont, Arizona, and other states. The work ranged from local crossings and historic highway bridges to major urban and regional transportation structures.

• Industrial and utility steelworkStructural steel fabrication1892

  The company produced engineered steelwork for waterworks, electric plants, pumping stations, industrial facilities, and other public utilities. Its capabilities covered fabrication, shipment, assembly, and erection, allowing it to deliver complete structural packages rather than only raw steel products.

• Gateway Arch steelworkArchitectural landmark fabrication1963

  For the Gateway Arch in St. Louis, Pittsburgh-Des Moines served as the steel fabricator and erector between 1963 and 1965. The assignment involved manufacturing and assembling the monument’s complex stainless-steel structural sections and remains the company’s best-known architectural project.

• World Trade Center forked columnsBuilding structural components1960

  During the 1960s, PDM fabricated the distinctive forked columns used in the World Trade Center complex. These components formed part of the innovative structural system of the original towers and demonstrated the company’s capacity to manufacture large, specialized members for major buildings.

• 2001Sale of principal assets to Chicago Bridge & IronM&A

  After decades as an independent steel fabricator, Pittsburgh-Des Moines entered an ownership transition at the beginning of the 2000s.

  What changed. Chicago Bridge & Iron acquired the company’s principal assets and operations. Reliance Steel & Aluminum separately acquired the steel distribution unit.

  Aftermath. The original company ceased operating independently, and its facilities and business lines subsequently passed through successor ownership.

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• 1993Permanent closure of the Des Moines fabrication siteOther

  The company’s original Des Moines works were severely damaged by flooding from the Raccoon River in July 1993.

  What changed. The Des Moines Heavy Bridge Division was closed permanently after the facility was damaged beyond salvage.

  Aftermath. The historic Iowa site was later sold, shifting the company’s operating footprint away from its original location.

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• 2024Francis Scott Key Bridge, originally fabricated by Pittsburgh-Des Moines, collapses after ship collision

  The Francis Scott Key Bridge in Baltimore, also known as the Outer Harbor Crossing, collapsed after being struck by the vessel Dali. Pittsburgh-Des Moines is identified in the reference material as the original fabricator; the collapse itself occurred long after the company’s independent operations ended.

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• 2016PDM-related headquarters reported in Elk Grove

  The reference material reports that PDM relocated its headquarters to Elk Grove, California. This appears to concern a successor or continuing PDM-branded operation rather than the original independent company.

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• 2013Veritas Steel acquires former PDM plants

  Veritas Steel LLC acquired former PDM steel plants in Eau Claire and Wausau, Wisconsin, and Palatka, Florida.

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• 2009CB&I closes the Warren fabrication plant

  Chicago Bridge & Iron closed the former Pittsburgh-Des Moines fabrication plant in Warren, Pennsylvania, in early 2009.

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• 2001Chicago Bridge & Iron acquires Pittsburgh-Des Moines assets

  Chicago Bridge & Iron Company acquired the company’s principal operations and assets. The transaction ended Pittsburgh-Des Moines’s existence as an independent operating company, while its steel distribution unit was acquired separately by Reliance Steel & Aluminum Co.

  M&A
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• 1993Raccoon River flood destroys the Des Moines Heavy Bridge Division

  Flooding in July 1993 damaged the company’s original Des Moines, Iowa, fabrication site beyond salvage. The facility was permanently closed and later sold.

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1. Pittsburgh-Des Moines Steel Co.