About CalPortland


CalPortland was established as California Portland Cement Company in 1891. The original cement plant, located at Mount Slover in Colton, California was west of the Mississippi River. In 1917 the company raised an American flag on the top of Mount Slover that flew 24 hours a day – only the third flag in the United States given permission to fly 24 hours a day (after the White House and the Capitol Building in Washington, D.C.).

In the early years, cement was loaded into wood barrels (made on-site) and transported by mule trains all across the west supporting the ongoing expansion of the United States.

Colton Cement was used to build the Hoover Dam, Los Angeles City Hall, the Los Angeles Memorial Coliseum, many of the roads in California, and the foundations for countless homes throughout the west. Eventually shipped to other states, structures using Colton cement can also be found in Nevada and Arizona.

With the demand for cement increasing, the company constructed a cement plant in Rillito, Arizona which began producing cement in 1949 (under the name of Arizona Portland Cement). As California and the surrounding states continued to grow, the company built a third plant in Mojave, California which began producing cement in 1956. Powered partly by wind-generated electricity, Mojave is a model in energy efficiency.

The Colton plant stopped producing cement in the mid-2000's as the cost of modernizing the plant was weighed against the amount of limestone left at the site. To ensure a continuing supply of cement, the Oro Grande cement plant was purchased in 2015. This plant is one of the most modern in the United States, able to produce significant quantities of cement each year.

Pioneer Sand and Gravel was formed in Seattle, Washington in 1910. Pioneer, which eventually became Glacier Northwest, has been a major supplier of construction materials throughout the northwest, producing and delivering ready-mix concrete and other building material supplies (aggregate, sand, gravel, etc.). Glacier’s growth expanded operations from areas near the Canadian border to south of Portland, Oregon. Glacier and the California Portland Cement Company were acquired around 1990 and merged into one company in 2005.

Union Asphalt/Coast Rock Products started in 1956. Originally selling aggregate and rock-related products, the company quickly expanded to road construction and asphalt, later adding ready-mix concrete to the business. Acquired by CalPortland in 2008 and now called the Central Coast region, this group serves communities from Santa Barbara up to Monterey County. 

The company has its roots in the building materials operations in the Southern California area since around 1919, dating back to the formation of the Union Rock Company. Over the years the company has merged with, acquired companies, and organically grown its materials business and today is a leading provider of ready-mix concrete under the name Catalina Pacific in the greater Los Angeles area. Chosen to provide the concrete for what is now the Intercontinental Los Angeles Downtown Hotel, the company provided 21,200 cubic yards of concrete in just under 19 hours. This record places the construction team and CalPortland in the Guinness Book of World Records for the largest continuous mat pour of concrete recorded.

Silver State Materials of Las Vegas, Nevada was acquired by CalPortland in 2008.  Formed in 1987, Silver State continues to build much of Las Vegas and the surrounding areas, including landmark casinos such as the Mirage Hotel and Casino, Buffalo Bills Hotel and Casino, Whiskey Pete’s Hotel and Casino, and the Gold Strike Hotel and Casino, as well as the spectacular Hoover Dam bypass bridge which is the highest and longest arched concrete bridge in the Western Hemisphere.

Re-entering the Arizona market in 2005, the company has grown to be one of the largest materials companies in Arizona serving the greater Phoenix and Tucson markets. Like its other markets, CalPortland plays a significant role in the building of roads, commercial buildings, sports stadiums, residential, and airports.

CalPortland’s most recent acquisition, Smokey Point Concrete/Skagit Ready-Mix was acquired in 2013. Dating back to 1970, CPC Materials (as it is now known) has provided concrete for roads, harbors, Indian casinos/hotels, commercial buildings, housing projects, and more from the Everett, Washington area up to the Bellingham, Washington area. CPC Materials lays claim to the closest CalPortland facility to the Canadian border (Hamilton Quarry in Hamilton, Washington).

Come make history with us!


CalPortland’s safety achievements are legendary.  Built on the philosophy of zero accidents for life, the company invests heavily in training and equipment designed to ensure that employees are properly prepared to do their jobs safely and to ensure they have the proper equipment to minimize risks.


CalPortland takes great pride in its stewardship of the environment. A leader in technological advances in the production of cement to minimize CO2 emissions, the first fleet of CNG ready-mix trucks in California and sixteen consecutive years as a US EPA ENERGY STAR® PARTNER OF THE YEAR award winner are just a number of achievements that distinguish the company as an environmental leader.

As a company that mines materials from the ground, we recognize our responsibility to return land to a condition that can be used appropriately. For example, a former sand and gravel mining operations in University Place (Tacoma), Washington along the Puget Sound was reclaimed by the company and with further development by the City of University Place, was turned in to the Chambers Bay Golf Course, home of the 2015 US Open Golf Championship.

Technical Expertise

CalPortland has been an innovative leader since it’s founding. Driven by science and engineering, CalPortland is widely respected in the industry for its technical expertise in creating products that meet specialized needs and exacting standards. Our customers rely on this expertise to complete highly complex jobs including the building of ultra-modern sports stadiums, dams, high rise buildings, airports, interstate highways and other infrastructure.


CalPortland believes in giving back to the many communities we serve by donating time, expertise, materials, equipment, and financial support. The partnerships CalPortland has developed with the communities, in which we work, live, and play reflects an important part of who we are. 

We recognize that we don’t just work in our communities – we live there too. Many of our employees are actively engaged in community work with the help of the company – projects such as Habitat for Humanity to sponsoring youth programs, donating materials for creating parks and other public spaces, and much more – come be a part of our community.


Cement is produced by crushing limestone, mixing with other materials, superheating, and then crushing the resulting material to a fine powder. When mixed with water, cement undergoes a chemical reaction and hardens into a rock-like material. It's uses include making concrete, asphalt, mortar, grout, and other materials where strength and/or fire resistance are desired.

CalPortland produces portland cement (named by the two chemists in England who created this type of cement in the 1820’s using limestone from the Isle of Portland off the coast of England) at three plants – one in Arizona and two in California. CalPortland is one of the top ten producers of cement in the United States.

Ready-Mix Concrete

Ready-mix concrete is made by mixing cement with water, rock (called aggregate), and sand. The strength of concrete comes from the aggregate captured inside the cured cement after it hardens – cement is hard but lacks the strength that concrete has.

Concrete is usually “batched” at a batch plant and loaded into the drum of a ready-mix truck – the drum turns or mixes the materials on the way to the job site – on arrival, the materials are mixed and ready to be unloaded from the drum.

Because concrete is created by a chemical reaction between cement and water when mixed, the time to get from mixing to job site is limited – usually no longer than 90 minutes. To ensure concrete can be delivered throughout a market effectively, there are usually multiple batch plants spread around a market area. CalPortland, across its markets, operates nearly 60 batch plants in seven major metropolitan regions across five states.


Aggregates are an important element in a wide range of construction applications, used in domestic and commercial projects. They make up a huge part of the composition of materials such as concrete and cement. Aggregates are, by definition, a collection of loose materials such as sand, gravel, and crushed stone. They are sourced from quarries/pits. Ready-mixed concrete is made from around 80% aggregates, and asphalt consists of 95% aggregates.

CalPortland operates approximately 25 aggregate quarries (or “pits”). Most of these mines are mined at ground level. CalPortland does do some mining underwater. The Santosh mine uses one of the most sophisticated floating dredges in the world to pull rock up from under a small lake, and can “mine” down to 150 feet below the surface of the lake.

Other Businesses

In addition to the three primary businesses of cement, ready-mix concrete, and aggregates, CalPortland produces pre-cast concrete forms (manhole covers, electrical vaults, wall blocks, and more) plus asphalt, and also has a general engineering construction division that builds and repairs roads.