She was the head coach of the
Canada women's national field hockey team from 1976 to 1995. During her time as coach, the team qualified for every major international games. Her teams medal-led at the World Cups in 1983 (silver) and in 1986, and bronze at the
Pan Am Games in 1987. van der Merwe coached the
York Lions from 1971 to 1999. During this time, the Lions won six silver and two bronze medals in the
Canadian Interuniversity Sport competition, and seven
Ontario University Athletics championships. Members of her team included 41 all-Canadians, over 55 conference all-stars, and more than 10 national team athletes. van der Merwe retired from teaching at
York University in 2002. ==Awards and honours==