Measuring 527 miles in length, freeways are one of the most important features of the man-made landscape in Los Angeles. But where does the material to make all of these freeways come from? Most of it comes from the City of Irwindale, a small suburb located 20 miles east of Los Angeles. In fact, today, when you drive along the 210 and 605 freeways through Irwindale, you can see the gigantic mining pits where the earth was removed to make much of L.A.'s freeways, along with other roads and structures. These pits form the economic backbone of this industrial city of only 1,422 residents and have played a major role throughout the city's history.Irwindale and its freeways have a deep relationship. 1987 photo by Javier Mendoza, courtesy of the Herald-Examiner Collection - Los Angeles Public Library.
The area we now know as Irwindale has always been heavily influenced by its natural environment. During the mid-19th century, the area was part of the Rancho Azusa de Dalton but was not considered valuable because of the overabundance of rocks and sand. A ranch overseer, Gregorio Fraijo, settled his family on about one hundred acres of land near the present day intersection of Arrow Highway and Irwindale Avenue. The land was not suitable for orchards or grazing cattle, but the nearby San Gabriel River provided an abundant source of water, and corn was successfully cultivated on the land. The area became a safe haven for immigrants, many from Sonora. Members of the Fraijo family began to marry family members of Facundo Ayon, a friend of Fraijo's from Sonora, and the Ayon family settled in the area. Generation after generation stayed on the land and today some native Irwindale residents can trace their descent back seven generations to the two families. A significant portion of Irwindale's population is still related to each other through blood or marriage.
Over the years, several names were applied to the dusty and rock filled area: Sonora Town, Cactus Town, Spanish Town, and Jackrabbit Town. The name Irwindale first appeared at the end of the nineteenth century. Its origin is disputed. One theory holds that the city was named after a man whose last name was Irwin, who introduced a gasoline-powered pump to the area's residents and then swindled them out of their rights to the San Gabriel River. Another theory suggests the name derives from California's thirteenth governor (serving from 1875-1880), William Irwin, who was the namesake for a post office opened in the area in 1895. Regardless of the origin, the name Irwindale gained widespread usage during the 1920s.
The rapid development of Los Angeles after the turn of the century - its population grew tenfold from 1900 to 1930 - stimulated the need for new roads and buildings and, by extension, quality construction aggregate. Aggregate is a category of material used in construction, which includes crushed rock, gravel (naturally broken rock), and sand. Aggregate is also a component of composite materials such as concrete and asphalt. The seemingly limitless need for aggregate would forever transform the dusty little town of Irwindale, which contains some of the highest quality and quantity of aggregate resources in all of Southern California.
Irwindales Reliance Rock Plant in 2009. Photo by Gary Leonard, courtesy of the Industrial Los Angeles Collection - Los Angeles Public Library.
Conveyor belt at Irwindales Reliance Rock Plant, 2009. Photo by Gary Leonard, courtesy of the Industrial Los Angeles Collection - Los Angeles Public Library.
Irwindale's rich supply of aggregate comes from the San Gabriel River, which carries broken rock out of the nearby San Gabriel Mountains and deposits it in the city. The mountains produce an especially large amount of rock and gravel because they are very steep (steepness affects how much mud, gravel, and rock a river can carry) and earthquakes cause the mountains to grow (which counteracts the effects of erosion and helps maintain steepness). The San Gabriel River flattens out in Irwindale, which causes the debris that was carried by the river to settle out. Because of these natural factors, rock and gravel have been accumulating in Irwindale for thousands upon thousands of years.
The first commercial-scale aggregate production sites began operating out of Irwindale in 1900. Railroad lines and stations were built to ship a steady supply of aggregate to locations through Los Angeles County. And as the number of automobiles increased in Los Angeles, so did the demand for better roads - and thus the need for crushed rock and gravel. Irwindale's rocks and gravel were also became part of many of L.A.'s best-known structures, including City Hall, the Biltmore Hotel, the Los Angeles Memorial Coliseum, Union Station, Dodger Stadium, the Bonaventure Hotel, and the Los Angeles Convention Center. otel,. HotedAnd when L.A. started building its first freeways, including the Arroyo Seco Parkway, materials mined from Irwindale were utilized. As Los Angeles grew, Irwindale's mines flourished.
Mining became the town's principal industry. Seventeen mining sites came to occupy 70 percent of the land in Irwindale. Interested in obtaining tax revenue from the mining operations, neighboring cities such as West Covina, Azusa, Baldwin Park, and Duarte began exploring the possibility of annexing Irwindale. Not wanting to be subjected to potentially higher taxes, the mining companies approached Irwindale's local leaders about the idea of incorporating Irwindale as its own municipality. An election was held in 1957. Out of the 153 votes cast, 133 were for incorporation. Irwindale subsequently became the fifty-sixth incorporated city in the County of Los Angeles.
In the early days of cityhood, the mining companies dominated the local economy and wielded enormous influence. This










