Robert Watt Lendrum was the fourth child of William Lendrum and Mary Watt. He was born in Fermanagh, Ireland on July 24, 1834. His family left Ireland in 1849 to come to Ottawa, where he worked with his father, who was a civil engineer. Robert was an Anglican and married Ella Brock (born October 22, 1849) in Hawksbury, Ontario on November 24, 1866.
Robert later taught school and went to Vankleek Hill to receive his certificate to teach school in Ontario. He taught for a while, then became articled to Robert Hamilton to become a land surveyor on January 8, 1874. He also kept a store and operated the telegraph station at Vankleek Hill. In 1880, he received his commission as a Dominion Land Surveyor, and went to Fort Garry (now Winnipeg), where he did considerable survey work. He practiced surveying in Ontario from 1882 to 1893
About 1896 he left the farm to engage in survey work for the government around Edmonton. He was still surveying, when he slipped on a sidewalk, resulting in a fractured hip, from which he died shortly afterwards on February 27, 1912. His wife had died on July 25, 1911 and they are both buried at Mount Pleasant Cemetery in Edmonton.