In 1992, Birkey led the Concordia Cavaliers to a National Association of Intercollegiate Athletics (NAIA) District Championship and into the title game of the NCCAA national tournament that same year. "The Navy" soccer team became a Cascade Conference power with NAIA regional tournament appearances in thirteen of the past sixteen years, and a top-twenty national ranking in fourteen of those years. Their highest ranking is fifth nationally. He directed Concordia to regional championships and NAIA national tournament berths in 1999, 2005, 2007, 2008 and 2010. In 2000, Birkey was named to the Cascade Conference Coaches Hall of Fame after receiving numerous district, conference, and regional Coach of the Year awards. Birkey has amassed over 400 wins and a .642 winning percentage at Concordia. He has earned eighteen championships during that time, including 13 of his last 15 Cascade Collegiate Conference championships. In 2007, Birkey led the Cavs to their tenth-straight regional tournament appearance after capturing the conference regular season title. Under his guidance the CU men's soccer program were crowned CCC Champions in 1998, 1999, 2000, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2010, 2011 and 2012 qualifying the CU team for the NAIA national tournament 7 times in program history. Birkey was instrumental in the 7.5 million dollar on-campus soccer stadium which opened in 2011 and worked closely with CU administrators and NIKE soccer to name the soccer field "Tuominen Yard" in respect to former CU soccer All-American (1994) and NIKE soccer marketing agent Jarkko Tuominen who died unexpectedly in September 2005. NIKE soccer maintained a strong relationship with the program and provided sponsorship until the galling closure of the program in 2020.