Thomas Coltrin Keefer (4 November 1821 – 7 January 1915) was a Canadian civil engineer. Born into a United Empire Loyalist family in Thorold Township, Upper Canada, the son of George Keefer and Jane Emory, née McBride, his father was chairman of the Welland Canal Company. After attending Upper Canada College he began his engineering training by working on the Erie Canal and continued his learning experience later on the Welland Canal.