In 1926, as America imagined a more connected future with the commission of Route 66, two brothers in rural Minnesota were already building it. Amos and Henry Duininck started grading dirt roads in Prinsburg with horse-drawn equipment. This modest work quietly grew into one of Minnesota’s – and the Midwest’s – most enduring infrastructure companies.

A century later, Duininck employs more than 1,400 people across Water Management, Construction and Materials (Heavy Civil, Concrete and Golf Course Construction), and Real Estate divisions. It remains family-owned through four generations, a rarity in an industry increasingly shaped by consolidation and private equity.

“What’s remarkable isn’t just that we’ve grown,” said Chris Duininck, President of Duininck Public Works. “It’s that we’ve remained family-owned and family-run. We have stayed focused on doing difficult work well and taking care of people.”

That doesn’t mean there haven’t been challenges. Resilience and adaptation defined the company’s early years. During the Great Depression, leaders restructured to survive. By the late 1930s, Duininck embraced new technologies, trading animal-powered equipment for trucks and crawler tractors. Its first asphalt project in the 1940s launched decades of expertise in Minnesota, one of the nation’s most punishing asphalt paving climates.

The 1956 National Interstate and Defense Highways Act opened new possibilities. The company helped build the backbone of America’s road system while contributing to advancements in asphalt quality and standards forged in the demanding Minnesota climate.

Bold moves have also defined the company. In 1985, 50 Duininck employee families relocated to Texas to build a new division from the ground up. Some of those original families remain part of Duininck’s Texas operations today, a multigenerational thread that runs through the company’s culture.

Meanwhile, much of the company’s other work happens out of sight. Since the 1980s, Duininck has built deep expertise in sanitary sewer, water, and storm systems, supporting critical infrastructure that communities rely on but rarely notice.

“A lot of what we do is invisible when it’s done right,” Chris Duininck said. After 100 years, that philosophy and a deep gratitude for employees still hold. “Our past and present employees have built this company,” Duininck added. “The next 100 years will depend on that same shared commitment.”