Eta Alpha chapter was formed as the local Phi Beta Psi in September 1981. Their mascot was a unicorn representing their uniqueness and their colors were blue and white. They became an Alpha Delta Pi colony in April 1982, and were installed on February 12, 1983 as the second NPC group on campus. The installation theme, "A Sweetheart of a Chapter," was chosen because initiation was close to Valentine's Day. At installation, the chapter presented a watercolor to the university that was hung in the Union. Katherine Peele McEwen was a long-serving advisor.