Founded in 1994, Terra Consulting Group began as a civil engineering firm in a basement just outside Chicago. We have since expanded our operations into five locations with over 70 professional team members who provide services in a multitude of wireless and infrastructure A&E disciplines.

Throughout our success, one thing has remained constant – the high-quality service we provide to our customers. We believe each customer engagement should be mutually beneficial. We consistently provide quality, innovation and sophistication in our work product, keeping customer service our top priority.

As of 2025, Terra is now a part of Colliers Engineering & Design, a national leader in multi-discipline engineering, architecture, and consulting services. This partnership expands our capabilities and geographic reach, enabling us to offer even more integrated solutions for wireless infrastructure, civil engineering, and land development projects.

Together, we are advancing the built environment to accelerate the success of our communities, clients, and people—while continuing to provide the exceptional service you’ve come to expect from Terra.

TEAMWORK

Work collaboratively toward a common goal and solution that best serves our customers and all stakeholders.

INNOVATION

Strive for continuous improvement, exploring new technologies and finding the best match between quality and value.

INTEGRITY

Do what is right, demonstrating respect, trust and transparency in all that we do.

COMMITMENT

Pursue excellence while honoring our commitments and agreements and expect the same.

John J. Zimmermann, P.E.

President

Thomas A. Zimmermann, P.E.

Vice President