CalPortland

CalPortland Company is an American building-materials producer whose principal businesses include cement, ready-mixed concrete, aggregates, asphalt, and related construction products and services. Although its corporate history began in Southern California, the company now maintains its headquarters in Summerlin, Nevada, and serves construction and infrastructure markets across the western United States. Its products are used in commercial and residential construction, roads, bridges, public works, industrial facilities, and other large-scale projects. The business was incorporated in Los Angeles County in 1891 as California Portland Cement Company. Its first cement plant was established at Mount Slover in Colton, California, where early production was packed in wooden barrels and moved partly by mule train. The company expanded during the late nineteenth and twentieth centuries, adding production capacity and distribution operations. It opened a plant at Rillito, Arizona, in 1949 and began production at Mojave, California, in 1956. These facilities helped establish a durable presence in the cement markets of the Southwest and western United States. During the 1960s and 1970s, California Portland Cement broadened its activities beyond cement. It entered ready-mixed and prestressed concrete through subsidiaries, developed hollow-core concrete products, pursued property and housing-related activities, and invested in petroleum exploration and coal mining. Some of these noncore businesses were later sold or separated as the company and its successors concentrated more heavily on construction materials. A decisive turning point came in 1984, when California Portland Cement merged with Consolidated Rock Company, a producer of sand, gravel, and crushed rock. The combined company was named CalMat Company, creating a vertically broader construction-materials enterprise. CalMat later sold several diversified subsidiaries, acquired asphalt operations, and faced a proposed takeover by investor Ron Brierley in 1988. The cement business was ultimately sold to Japan's Onoda Cement, which exercised an option to acquire California Portland Cement and related ready-mix operations. The transaction was completed in 1990. Onoda Cement subsequently merged with Chichibu Cement in 1994 and Nihon Cement in 1998. Those combinations produced Taiheiyo Cement Corporation, which remains CalPortland's ultimate parent through Taiheiyo Cement USA. The company adopted the CalPortland Company name in 2008. Its original Colton plant ceased production in 2009 during a restructuring prompted by reduced demand during the Great Recession. Today, CalPortland operates as a regional building-materials platform rather than as a publicly traded standalone company. Its activities include cement manufacturing and distribution, aggregate extraction, ready-mixed concrete, asphalt, and construction-material supply. Subsidiary Glacier Northwest extends the company's operations into Washington and has a long history in sand and gravel production around Puget Sound. CalPortland's business has also been involved in significant labor, environmental, and competition-related legal proceedings, including the United States Supreme Court case Glacier Northwest, Inc. v. Teamsters. The company positions itself around reliable supply, technical expertise, and service to western construction markets.

CalPortland traces its origins to the incorporation of California Portland Cement Company in Los Angeles County on September 18, 1891. Its first facility operated at Mount Slover in Colton, California. Early cement was packed in wooden barrels and transported by mule trains before the company developed more substantial storage and distribution capacity. By 1896, the plant was producing hundreds of barrels per day and also making products such as marble dust and lime. The company expanded its western production footprint in the postwar period. Arizona Portland Cement opened a plant at Rillito, Arizona, in 1949, while a Mojave, California, cement plant began production in 1956. California Portland Cement also developed businesses outside its core cement operations. In the 1960s it entered prestressed and ready-mixed concrete, established Spancrete for hollow-core slabs and beams, and pursued property development and housing finance. It acquired a majority interest in State Exploration, a petroleum exploration business, in 1969 and founded Soldier Creek Coal Company in Utah in 1971, partly to supply coal to its cement plants. In 1984, California Portland Cement merged with Consolidated Rock Company, also based in Los Angeles. Consolidated Rock produced sand, gravel, and crushed rock, so the merger created a more integrated construction-materials company. The combined enterprise became CalMat Company, with California Portland Cement shareholders holding a majority interest. CalMat sold Statex Petroleum and Soldier Creek Coal in 1985, acquired Coast Asphalt in 1986, and subsequently focused more closely on aggregates, asphalt, cement, and related materials. CalMat became the subject of a potential hostile takeover in 1988 when New Zealand investor Ron Brierley accumulated approximately 19 percent of its shares and discussed an offer for the company. Brierley ultimately sold his stake to Onoda Cement. As part of that transaction, Onoda obtained an option to acquire California Portland Cement and a group of Los Angeles-area ready-mixed concrete plants. Onoda exercised the option, completing the acquisition in 1990. The reported purchase price for California Portland Cement was $316 million. Onoda Cement later merged with Chichibu Cement in 1994 and Nihon Cement in 1998. The resulting company, Taiheiyo Cement Corporation, became CalPortland's ultimate parent, with ownership held through Taiheiyo Cement USA. California Portland Cement changed its name to CalPortland Company on June 20, 2008. The Colton facility, the company's original cement plant, stopped production on November 20, 2009, as the company responded to the sharp decline in construction demand associated with the Great Recession. CalPortland's subsidiary Glacier Northwest has a separate but related history in Washington State. Its roots extend to sand and gravel extraction near Steilacoom, where materials were supplied for late-nineteenth-century military construction around Puget Sound. Successor operations supplied aggregates for projects including bridges, stadiums, civic facilities, and naval shipyard infrastructure. Glacier Northwest became involved in a major labor-law dispute after a 2017 strike by Teamsters Local 174 drivers. The case eventually reached the United States Supreme Court, which ruled in 2023 that federal labor law did not bar a claim alleging intentional destruction of property connected with strike conduct. The modern CalPortland business is centered on cement, aggregates, ready-mixed concrete, asphalt, and distribution. It operates across western United States markets and serves both private construction and public infrastructure. Its corporate development reflects a long-term shift from a Southern California cement producer into a broader, vertically integrated regional building-materials supplier within the Taiheiyo Cement Group.

1. 2023Supreme Court rules in Glacier Northwest labor case

   The Supreme Court held that the National Labor Relations Act did not preempt certain property-damage claims related to strike conduct.

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2. 2009Colton plant production ends

   Production ceased at the company's original Colton plant during a restructuring prompted by reduced demand.

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3. 2008Company adopts CalPortland name

   California Portland Cement Company changed its name to CalPortland Company.

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4. 1998Taiheiyo Cement becomes ultimate parent

   The merger of Onoda Cement and Nihon Cement helped create Taiheiyo Cement Corporation, the current ultimate parent.

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5. 1990Sale to Onoda Cement completed

   Onoda Cement acquired California Portland Cement from CalMat, beginning the company's Japanese ownership.

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6. 1988Onoda Cement acquires a strategic position in CalMat

   Onoda Cement purchased Ron Brierley's approximately 19 percent stake in CalMat and obtained an option to acquire California Portland Cement.

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7. 1984Merger creates CalMat Company

   California Portland Cement merged with Consolidated Rock Company, combining cement operations with sand, gravel, and crushed-rock businesses.

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8. 1956Mojave cement plant begins production

   A third cement plant began operating at Mojave, California.

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9. 1949Rillito, Arizona, plant opens

   Arizona Portland Cement opened a cement plant at Rillito, extending the company's production network beyond California.

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10. 1891California Portland Cement Company incorporated

    The company was incorporated in Los Angeles County, California, establishing the corporate foundation of the later CalPortland business.

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11. 1891First Colton cement plant established

    The company began cement production at Mount Slover in Colton, California.

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Regional, vertically integrated construction-materials supplier serving western United States infrastructure and building markets.

• CementCement1891

  Cement is CalPortland's historic core product and is manufactured and distributed for concrete production, masonry, commercial construction, transportation infrastructure, and public works. The company developed from a Southern California cement producer and later expanded into Arizona and other western markets. Its cement operations are complemented by distribution facilities and downstream ready-mixed concrete and aggregate businesses.

• Ready-mixed concreteConcrete1961

  CalPortland supplies ready-mixed concrete for building foundations, structural frames, roads, bridges, industrial sites, and other construction applications. Ready-mix operations became part of the company's broader portfolio through expansion and acquisitions, including operations associated with its California and Washington businesses. The offering combines material supply with local batching, delivery, and project-support capabilities.

• AggregatesAggregates1984

  The company produces and distributes sand, gravel, crushed rock, and related aggregate materials. These materials are used in concrete, asphalt, road base, drainage, foundations, and general site development. Aggregate capabilities were strengthened through the 1984 merger with Consolidated Rock and through the history of Glacier Northwest in the Pacific Northwest.

• AsphaltPaving materials1986

  CalPortland participates in asphalt and paving-material supply for roads, commercial surfaces, and other transportation projects. Its asphalt presence was expanded through the acquisition of Coast Asphalt by the CalMat predecessor in 1986, complementing the company's cement and aggregate operations.

• Precast and prestressed concrete productsPrecast concrete1966

  Earlier company operations included prestressed and precast concrete products, including hollow-core slabs and rectangular beams through the Spancrete subsidiary. These activities reflected the company's historical effort to extend beyond cement manufacturing into engineered concrete components and construction systems.

• 2009End production at Colton plantStrategy

  The Great Recession reduced construction demand and led the company to restructure its production network.

  What changed. CalPortland stopped cement production at its original Colton, California, facility.

  Aftermath. The company continued operating as a western regional supplier using its remaining manufacturing, distribution, aggregate, concrete, and related assets.

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• 2008Adopt the CalPortland Company nameStrategy

  The company had evolved from California Portland Cement into a broader western construction-materials enterprise.

  What changed. California Portland Cement Company changed its corporate name to CalPortland Company.

  Aftermath. The new name better represented the company's wider geographic reach and product portfolio.

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• 1990Sell California Portland Cement to Onoda CementM&A

  The transaction followed takeover pressure on CalMat and Onoda Cement's acquisition of a substantial CalMat shareholding.

  What changed. Onoda Cement exercised its option and purchased California Portland Cement and associated ready-mix operations from CalMat.

  Aftermath. CalPortland became part of a Japanese cement group and ultimately came under Taiheiyo Cement ownership.

  Acquisition price. $316 million (1990)

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• 1984Merge with Consolidated Rock CompanyM&A

  California Portland Cement sought greater scale and a broader construction-materials portfolio through combination with a producer of sand, gravel, and crushed rock.

  What changed. The companies merged to form CalMat Company, combining cement, aggregates, and related operations.

  Aftermath. The merger created a more vertically integrated western building-materials company and provided the corporate structure from which the present CalPortland business emerged.

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• 2011Clean Air Act settlement involving Mojave plantControversy

  CalPortland reached an agreement with the EPA and Department of Justice over allegations involving Clean Air Act compliance at the Mojave plant. The resolution included penalties and commitments to reduce nitrogen-oxide and sulfur-oxide emissions.

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• 1980Cement price-fixing litigationControversy

  California Portland Cement was among approximately 50 defendants accused in a lawsuit concerning alleged cement-price coordination from 1968 through 1976. The company denied illegal activity but paid a reported settlement of $6.5 million.

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• 1912Grand-jury investigation over alleged cement price differencesControversy

  California Portland Cement and Riverside Portland Cement were investigated after a San Bernardino water official questioned why cement prices in San Bernardino were higher than prices in Los Angeles. Both companies denied price fixing and attributed pricing changes to competitive conditions.

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• 2023Glacier Northwest v. Teamsters reaches the U.S. Supreme Court

  The Supreme Court reversed and remanded a Washington Supreme Court decision in an 8–1 ruling, holding that the National Labor Relations Act did not preempt a claim alleging intentional destruction of company property during a strike.

  LawsuitRegulation
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• 2009Original Colton cement plant stops production

  CalPortland halted production at its historic Colton, California, plant while restructuring in response to weakened demand during the Great Recession.

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• 1990CalMat sells California Portland Cement to Onoda Cement

  Onoda Cement completed its acquisition of California Portland Cement from CalMat, beginning CalPortland's ownership by a Japanese cement group.

  M&A
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1. CalPortland Company
2. CalPortland official website