Charles Hassard was employed in 1883 to select subsidiary points for the principal triangulation of Natal and was still in that colony in 1889. During 1893-1894 he resided in Komatipoort in the South African Republic (Transvaal), from where he requested a permit to import a hunting rifle and ammunition. From 1902, following the Anglo-Boer War (1899-1902), he was superintendent of irrigation in the Orange River Colony (now the Free State) and in 1903 spent some time at the Mushroom Valley irrigation works near Winburg. In 1907 he read a paper on "Irrigation in the Orange River Colony" at the annual meeting of the South African Association for the Advancement of Science. Only the title of the paper was published in the association's Report. He was not a member.
By 1908 Hassard resided in Durban. In 1915 he donated ants from Carnarvon to the Albany Museum, Grahamstown. He was married to Kathleen May Hassard, who died in 1949.