Mr. and Mrs. Stephen Lee Coffman of Gray, are pleased to announce the engagement of their daughter Ericha Marie to Thomas Christopher Garrison, son of Stephen and Carol Garrison of Johnson City. The bride-elect is a 2007 graduate of Daniel Boone High School and will receive a degree in cardiovascular technology from Northeast State Community College in August. She is the granddaughter of Lou Egger of Johnson City, and Mr. and Mrs. Niles Lee Coffman of Kingsport.Her fiance is a 2003 graduate of Science Hill High School and holds a degree in aviation science from Utah Valley State College. He is employed by the City of Johnson City. He is the grandson of Mary Collins of Johnson City, the late Tom Collins and the late David and Dottie Garrison.An open-church wedding is planned for 2 p.m., Aug. 21, 2010, at Tri-Cities Baptist Church, 171 Promise Land Drive, Gray.