About Us

Building North Central Illinois with Experience, Reliability, and Generational Vision

We are Gillan Construction, LLC — a family owned construction company serving North Central Illinois. Although we officially formed our company in 2021, our history extends back more than three decades. In that same year, we purchased AWSS – Area Wide Septic Service - from Jeff’s parents, continuing the first generation’s longstanding commitment to integrity, hard work, and dependable service.


What began as a respected septic and sewer service provider has grown into a full service heavy civil, commercial, and municipal construction company positioned to meet the evolving infrastructure needs of our region.

Our Growth: From AWSS to Full Civil Construction

Since acquiring AWSS and expanding our capabilities, we have built a diverse portfolio of civil and infrastructure projects. Today, our work includes:


  • Excavation & grading
  • Structural and flatwork concrete
  • Underground utilities (water, sanitary, storm)
  • Bridge & structural construction
  • Demolition & site clearing
  • Full site preparation & development


We understand the complexity and regulatory demands of municipal and commercial work. Our team coordinates directly with engineers, project managers, inspectors, and local officials to ensure proper sequencing, accurate documentation, and full compliance with all safety and code requirements. Whether we’re installing a water main, constructing a structural foundation, or managing a multiphase development site, we deliver results built to last.

Union Built. Professionally Delivered.

We are a union contractor, and as owner operator, Jeff is a proud member of IUOE Local 150. This reflects our commitment to highly skilled labor, safe operations, and the highest standards of workmanship.


As a licensed, bonded, and insured contractor, we bring the resources, union workforce, equipment, and experience necessary to support essential infrastructure across North Central Illinois. Every project receives disciplined planning, transparent communication, and consistent, professional execution.

Our Family Legacy — Built for the Next Generation

Gillan Construction is being built with long term vision, carrying our family’s legacy from one generation to the next. Each of our sons brings unique talents that will shape the company’s future:


  • Grady is studying Construction Science and Management at the University of Tennessee, preparing to support our company through strategic planning, operational leadership, and executive level management.
  • Gavin is in high school and exploring Construction Management programs, but he is especially passionate about operating equipment and handson field work. His future contributions will focus on field operations, equipment leadership, and site level supervision.
  • Leo, in middle school, excels in math, analysis, and problem solving. He is drawn to the business and administrative side of what we do and will likely support future accounting, office operations, or financial leadership roles.


As we continue to grow, our family brings together strategic leadership, skilled field operations, and strong business management — ensuring Gillan Construction thrives for generations.

Leadership

Jeff Gillan — Owner & Operator

Jeff brings more than 20 years of diverse construction experience to Gillan Construction, including nearly 15 years with D. Construction, where he advanced from Project Manager to Bridge Superintendent and helped lead multiple award winning civil and structural projects across Illinois.


His background in structural concrete, bridge work, scheduling, project management, and field operations provides the foundation for the disciplined, high quality work our company is known for.


He holds a degree in Construction Management from Bradley University and completed the Illinois Roadbuilders Emerging Leaders Program, and he continues to stay engaged in both the industry and our community through service on the Illinois Valley Contractors Association Board of Directors and as Treasurer of the Spring Valley Fire Protection District Board.


In addition to operating Gillan Construction, Jeff co-owns Turnkey Contracting by Gillan with his wife, Liza, and serves as its Vice President of Business Development.

Let’s Build Together

If you’re planning a commercial or municipal project anywhere in North Central Illinois, our team is ready to review your scope, schedule, and site conditions — and deliver a plan that works.

Gillan Construction, LLC — A legacy of service. A future built on strong foundations.