Ennis has dedicated much of her adult life to the service of others. She is truly an active volunteer par excellence. Once her children were settled in school, she began her volunteer and professional service.
In 1966 she accepted a position as a swimming instructor at the University of Saskatchewan and was aquatic co-coordinator until her retirement in 1982. She has also been a swimming instructor for the city of Saskatoon and has coached and officiated at numerous swimming and synchronized swimming competitions. When Saskatoon hosted the 1971 Canada Winter Games Ennis was technical director for synchronized swimming.
For over 38 years Ennis has been a volunteer instructor for the Red Cross; represented Saskatchewan at the National Water Safety Committee and has served as an instructor and examiner of the Royal Life Saving Society.
Recognition awards have been presented to her by the University of Saskatchewan, the Royal Life Saving Society, Sask Sport and Century Saskatoon. Ennis was one of two Canadians to first receive the Order of the Red Cross in 1984.