After his retirement Glenn remained active at the university and with the City of Corvallis as a councilor, and frequently visited Apperson Hall (until he was well into his 80s) to have coffee with faculty members and staff and dispense advice on engineering, teaching and politics.

When he was 81, the Glenn W. Holcomb Scholarship was established by the School of Engineering as a way, according to the school's announcement, "of recognizing the many contributions Professor Holcomb made to engineering education, to the profession of civil engineering, to the betterment of Oregon State University and the City of Corvallis, and to enriching the lives of his students and many friends throughout a career that spanned 46 years." The scholarship continues to aid students to this day.