After returning to Oregon from South America, Birkey became limited as a player due to several knee surgeries and focused on his coaching career leading Columbia High School in Troutdale, OR. Having played under Clive Charles, he was invited to coach with him at the club level and worked numerous years as a staff coach at the Portland Timbers youth camps along with Timbers players from the late 1970s and early 1980s. It was Birkey's professional relationship with Charles that set the model for much of his coaching philosophy. In 1985, he began coaching at the collegiate level at Portland Community College while working in Sports Medicine. After earning his master's degree in Kinesiology from Portland State in 1986, he began coaching at Concordia University, Portland, in 1988. Since that time, he has become most widely known for the prolific success of Concordia men's soccer. A significant milestone was made for his Concordia soccer program as CU athletics gained membership to the Great Northwest Athletic Conference (GNAC) and transitioned to NCAA DII competition in the Fall of 2015.