Inside Pre-Con’s expansion and its push into the most complex markets in the industry
When the Zarraonandia brothers talk about precast concrete, it’s not just a job—it’s a lifetime story poured into every form, mold and structure that their company produces.
David Zarraonandia, president of Pre-Con, remembers oiling the forms with a concoction
of diesel and waste oil at the age of 15. By the time Dan Zarraonandia, vice-president of Pre-Con Products, was 5 years old, he was already riding on crane trucks and helping his father rig manhole shafting at job sites. It was a different era, one where a family business truly meant growing up inside the work. More than 60 years after their father founded Pre-Con Products, that early exposure still shapes how David and Dan lead the company today.
Their father, Don Domingo Zarraonandia, started the business in 1963 in Thousand Oaks, Calif., and later moved operations to Simi Valley in 1971. What began as a small precast operation focused on pipe and manholes has evolved into a company known for tackling some of the most technically demanding projects in the industry.
Yet the foundation has never changed.
“We treat our people right. We value what they do,” Dan said. “That’s evidenced by the longevity and multi-generational staff.”
That culture of loyalty and craftsmanship became especially important in the late 1980s and early 1990s, when the company faced growing pains after the passing of their father in 1987. After graduating from UCLA, Dan had been pursuing other business opportunities when David called him in 1991. The company needed help. Together, the brothers stabilized operations, refocused on quality and laid the groundwork for decades of expansion.
What sets Pre-Con apart today is not just what it makes, but what it is willing to attempt. While many precasters stay within safe, repeatable product lines, the Zarraonandia brothers have leaned into complexity. Over the years, that has meant expanding beyond sewer manholes and reinforced concrete pipe to include massive vaults, stormwater structures and highly specialized projects that few competitors are willing to undertake. Pre-Con has shipped precast foundations to Antarctica for the U.S. government and produced custom structures for the Department of Defense. This work demands both technical creativity and unwavering precision.
Those experiences shaped how the brothers think about growth. They are not chasing volume for its own sake. They are building capacity for projects that solve real problems.
“We realized that we have a special ability in doing unique, difficult projects that a lot of larger competitors would rather avoid,” Dan said.
Nowhere is that clearer than in Southern California’s stormwater crisis. More than a century ago, the region planned to capture rainfall and recharge groundwater. That idea was shelved when imported water from Northern California and the Colorado River became available. Today, with climate stress and water scarcity mounting, agencies are returning to that original concept on a massive scale.
Instead of sending rainwater through concrete channels and out to sea, the region is investing in systems that capture, treat and infiltrate stormwater back into aquifers. Los Angeles County voters approved a property tax measure that generates hundreds of millions of dollars annually for these projects, while the City of Los Angeles funds similar initiatives to reduce dependence on imported water.
The scale of these efforts is staggering. Some projects require thousands of large precast modules, all manufactured and stored before installation begins. That reality is what led Pre-Con to its most ambitious move yet.
In 2019, while discussing one of Los Angeles’ major stormwater projects, an engineer asked David how the company could possibly produce 6,000 modules weighing up to 22,000 pounds at its Simi Valley facility. The honest answer: it couldn’t.
“That’s when we realized we didn’t have the space. We had to find a larger piece of property,” David said.