Swimming the anchor leg for Canada's third-place team in the women's 4x100-metre freestyle relay, she won an Olympic bronze medal, together with teammates Angela Coughlan, Marilyn Corson and Elaine Tanner.

[1] Through the 1960s and 1970s, Canada produced a remarkable number of world-class swimmers and Lay is notable for her contributions to that success.

As a coach of women swimmers, she held positions at California State Polytechnic College in Pomona, California State University at Hayward, the University of Western Ontario, and the Ottawa Kingfish Swim Club.

In 2015, she was a member of the planning committee for the National Conversation on Women in Sport at Laval University in Quebec City.

Lay is an adjunct professor in the School of Human Kinetics at the University of British Columbia, a member of the Board of Directors of ParticipACTION, and co-chair and honorary board member of the BC Games Society.

Following the end of her competitive career, Lay came out as lesbian, and was a coordinator of the Pride House at the 2010 Winter Olympics.