Marcel Pequegnat was a civil engineer in Kitchener, Ontario, who spent his professional career with the Kitchener Water Commission as superintendent and consultant. He was also involved in the Grand River Conservation Commission and the Arthur Pequegnat Clock Company.

Pequegnat was born in Berlin (now Kitchener) April 27, 1886 to clockmaker Arthur Pequegnat and his wife Hortense (nee Marchand), Marcel studied engineering at the University of Toronto. After graduating he taught at the University and worked for several summers for the Berlin City Enginneers. In 1910-1911, he surveyed land in Manitoba, and in 1913, he was appointed assistant city engineer in Berlin. In 1919, he became superintendent of the Kitchener Water Commission, holding this position until 1957 when he became a consultant until retiring in 1970. Pequegnat also served for 27 years on the Kitchener Planning Board and for 30 years on the Kitchener Suburban Roads Commission. He was president of the Arthur Pequegnat Clock Company from 1940 to 1964, though for most of that time the company was dormant, having ceased clock production by 1942.

Pequegnat was a founding member of the Grand River Conservation Commission (GRCC) when it formed in 1932 and served as vice-chairman from 1938 to 1952, chairman from 1953-1959, and chief engineer from 1962 to 1965. His period of service with the GRCC coincided with the building of the Shand, Luther, and Conestogo dams. He was also Life Member of the Engineering Institute of Canada, a charter member of the Professional Engineers of Ontario, and received their Citizenship Award in 1973. He also was awarded Life Membership in the American Waterworks Association.

Pequegnat married Nellie Elizabeth Klippert (1888-1972) December 28, 1910 and together they had three children. He died in 1988 and was buried alongside Elizabeth in Mount Hope Cemetery.