Lonnie Haefner (July 7, 1941 - March 5, 2025)

The family of Dr. Lonnie Edward Haefner, PhD, PE, wish to announce Lonnie passed peacefully at home in Kirkwood, Missouri, with his loving wife of 59 years, Jean Martin Haefner, by his side. He is also survived by daughter Erica Haefner Ferro (David); son Bradley Martin Haefner; and grandson Dylan Joseph Haefner. Lonnie was preceded in death by his father, Lawrence Haefner; his mother, Pearl Norton Haefner; his brother, Lawrence Ray Haefner; and many beloved rescue dogs.

Lonnie was born in Webster Groves, MO. Lawrence was a hard-working barber, woodworker, and outdoorsman; Pearl was a proud stay-at-home mother. They enjoyed taking Lonnie to Lake of the Ozarks, where he loved to fish and boat. Their support, paired with Lonnie’s determination, earned him admission to his beloved Northwestern University, becoming the first in his family to earn a college degree. While at Northwestern, Lonnie enthusiastically began his lifelong support of the Wildcats. Upon graduating with a BA degree from Northwestern, Lonnie returned to St. Louis and began working at the St. Louis County Division of Traffic, where he met the love of his life, Jean. Six months later they were married in a small private ceremony.

Lonnie went on to earn a Master of Science in civil engineering at the University of Illinois; in 1967, he returned to Northwestern, where he was designated a Fellow at the Transportation Center, and he obtained his Ph.D. in civil engineering. 

Lonnie had a long history of achievement in the field of transportation engineering. After time at General Motors and the University of Maryland, he went on to become a fully tenured professor emeritus of civil engineering at Washington University in St. Louis. During his twenty-eight years at WashU, he directed programs in transportation and urban systems engineering and international project management and finance; authored and co-authored 219 papers and three books; and mentored many students. 

Lonnie consulted extensively on state and national transportation issues, testifying before Congress and representing public policy and infrastructure needs through his consulting firm, L.E. Haefner Enterprises, Inc. He was an active member in many industry organizations, recognized for his leadership by the American Road & Transportation Builders Association, the Transportation Research Board and the Missouri House of Representatives, and as a Life Fellow of the Institute for Transportation Engineers. He gave generously of his time, serving as a Life Regent and a member of the Northwestern University Leadership Council. He was proud to receive the Northwestern University McCormick School of Engineering & Applied Science Award of Merit in 2013, in recognition of his accomplishments and impact.

While Lonnie was proud of his professional achievements, he took the most pride in his family. He and Jean created a close-knit family, always finding time to coach Brad’s little league baseball team, The Bankers; cheer at Erica’s swim meets; pet one of their many adopted dogs; and listen to some good bluegrass music. They emphasized the importance of education, and also encouraged making time for fun and other pursuits. 

His early love of fishing and boating continued, and he introduced his children early on through many trips to Lake of the Ozarks. He loved sailing with his wife in their Flying Dutchman and taking his son and daughter out in his bass boat to “put the hammer down” to run at top speed to a favorite fishing spot. An Eagle Scout himself, he encouraged both his children to be active in scouting, where they each grew to love the outdoors. Lonnie loved to laugh, full of antics and creative, ready-made puns that always entertained his loved ones.

Lonnie will be dearly missed by his family, friends, and colleagues. The family would like to thank AccentCare, especially Lisa and Yolanda, for their caring, attentive and high-quality support to help Lonnie pass peacefully. Lonnie will be remembered privately by his family. 

In lieu of flowers, donations are welcomed at the Humane Society of Missouri (hsmo.org) or the Northwestern University Arch Scholars program for first generation students (weinberg.northwestern.edu/undergraduate/first-year-transfer/first-year/arch-scholars/support-arch-scholars.html).

This obituary was published in the Webster-Kirkwood Times on Friday, March 21, 2025.