Leadership2025-10-16T15:01:57+00:00

From the Blog

Testimonials

Sean has been doing a great job for the Town of Timnath, providing thorough development reviews of roundabouts and traffic studies. His strong knowledge of LCUASS and professional approach have been valuable in supporting safe and efficient community growth.

Kim Koivuniemi, PE, Senior Civil Engineer, Town of Timnath

I had the pleasure of working with Sean (Kellar Engineering) on the 37th Street Connector Project in Loveland, Colorado. Sean provided traffic-engineering design support to the J-U-B Engineers team, which included roundabout design and a full traffic study for the corridor. Throughout the design process, Sean was responsive, supportive, and provided common sense solutions. I would highly recommend Kellar Engineering for traffic engineering and project management.

Dan Tuttle, P.E., Project Manager, J-U-B Engineers, Inc.

I’ve had the pleasure of working with Sean Kellar at Kellar Engineering on several projects. He is easy to work with, extremely responsive, follows through on his commitments, and is an excellent traffic engineer. I enjoy working with him and wouldn’t hesitate to recommend him for all of your traffic engineering needs including roundabout design.

Sam Eliason, PE, LEED AP, UNITED CIVIL DESIGN GROUP, LLC

Leadership

Sean Kellar, Kellar Engineering, Traffic Impact Study Kansas City

Sean Kellar, PE, PTOE
Principal Engineer

Sean has over   years of Transportation/Traffic Engineering experience. Sean’s wide range of expertise includes: intersection re-design, roundabout design, traffic modeling, bike/pedestrian facilities, traffic impact studies, traffic signal warrant analysis, parking studies, access management coordination, and neighborhood collaboration. Sean’s experience in both the private and public sectors; passion for safety and excellence; and strong communication and collaboration skills bring great value to any project. Outside of work, Sean enjoys: spending time with family, friends, playing music, biking, running, hiking, and being outdoors.
Education and Certification:
  • Registered Professional Engineer, State of Colorado (License #38650)
  • Registered Professional Engineer, State of Arizona (License #45781)
  • Registered Professional Engineer, State of Missouri (License #2015027449)
  • Registered Professional Engineer, State of Kansas (License #27166)
  • Registered Professional Engineer, State of Wyoming (License #15954)
  • Registered Professional Engineer, State of Idaho (License #P-20795)
  • Professional Traffic Operations Engineer (PTOE) (Certificate #2647)
  • Bachelor of Science in Engineering , Emphasis in Civil Engineering Arizona State University, Tempe, AZ
Professional Work Experience:
  • Missouri Department of Transportation (MODOT), Lee’s Summit, MO
    District Traffic Engineer, Kansas City District
  • City of Loveland, CO
    Senior Civil Engineer, Transportation Development Review – Public Works
  • Kirkham Michael Consulting Engineers, Greeley, CO
    Project Manager
  • Dibble and Associates Consulting Engineers, Phoenix, AZ
    Project Engineer