William Roe was probably the eldest son of William Roe, a wood turner, and his wife Mary Ann, who arrived in the Cape Colony as British immigrants in July 1858. They were accompanied by their three children, including William junior, aged 10. In October 1864 William senior, then described as an artist, was declared insolvent at Graaff-Reinet. Either the father or, more likely, the son became the photographer W. Roe who took panoramic pictures of Graaff-Reinet and the diamond diggings at Kimberley in 1870, and who practiced as the photographer William Roe in Graaff-Reinet from 1878 to 1894. During 1895 he forwarded specimens of insects from Graaff-Reinet, with information about the damage they caused, to the newly appointed government entomologist of the Cape Colony, Charles P. Lounsbury*, in Cape Town.
During 1897, while still residing in Graaff-Reinet, Roe published two articles in the Agricultural Journal of the Cape of Good Hope. One of these, "Notes on the geology of the Midlands in relation to water seeking" (Vol. 10(3), pp. 165-170), dealt with the influence of dolerite dykes, and the size of the catchment area at a site, on the amount of available ground water. In the other, "Notes on a form of irrigation well suited to a large portion of the Colony and especially the Karroo and inland plateau" (Vol. 10(1), pp. 25-27), Roe expressed the view that inland lakes had fairly recently existed in the interior of southern Africa, but had dried up. (A specific proposal for restoring inland lakes assumed to have existed in the Kalahari was published by F. Gessert* of Namibia this same year, which probably formed the basis of E.H.L. Schwarz's* later "Kalahari Sheme"). Roe proposed that all the gaps in the dolorite dykes of the Karoo where rivers passed through them should be filled up. Thus run-off would be reduced and groundwater increased, while the series of dams created in each river could be used for irrigation. This William Roe may have been the same person as Corporal William Roe, who kept a diary during his participation in the Anglo-Zulu War of 1879.