Robert Owen Wynne-Roberts (sometimes Roberts, Robert Owen Wynne), civil engineer, was the son of Owen Roberts and his wife Annie Wynne. He was an associate member, and from 1905 an ordinary member, of the (British) Institution of Civil Engineers. In about 1906 he was elected a Fellow of the Royal Sanitary Institute.
He came to the Cape Colony in or before 1898 and by 1902 was employed as water engineer to the Cape Town waterworks, a post in the City Engineer's Department that he held to 1906 or 1907. During these years he investigated and reported on several water schemes for the growing city. His Report by the water engineer, in re Berg River Hoek and Wemmer's Hoek water schemes (1903) and Memoranda on reproposed augmentation of the water supply of the city of Cape Town (1904) both contained rainfall tables compiled from observations of ordinary and mountain rain gauges, distributed over the catchment areas. With R.H. Charters* and R.W. Menmuir he investigated ten proposed schemes to augment the water supply of Cape Town and some of the suburbs, and published a Final report... (1904) on their work. He also drew up plans showing the levels of a proposed pipeline from the reservoir at Groot Drakenstein, dividing to supply both the Molteno reservoir and the Newlands reservoir (13 sheets, 1904). Shortly after leaving the Colony he published a History and description of Cape Town waterworks... (1908) in which he described both the existing water schemes, such as Molteno and Woodhead, and schemes proposed for the future, such as French Hoek, Wemmershoek and Steenbras.
Wynne-Roberts was a foundation member of the Cape Society of Civil Engineers. At its first meeting, in January 1903, he was elected a member of its committee for that year, and served on the committee again in 1905. In May 1903 he presented a paper on "Sewage disposal" before the society, which became the first paper, after the president's brief address, to be published in the society's Minutes of Proceedings (Vol. 1, pp. 10-15). Two years later, in May 1905, he addressed members on "Three American dams". In 1902 he became a foundation member also of the South African Association for the Advancement of Science.
At some time during his career Wynne-Roberts designed a "hydraulic calculator for water mains and circular sewers", consisting mainly of a complicated circular logarithmic slide rule. The device was published in the form of a booklet, with explanations in the form of example calculations.
After leaving the Cape Colony he settled in Canada. There he published a Report on coal and power investigations (1913) which dealt with the use of lignite in Saskatchewan. Later he worked in Ontario as a sewerage engineer for the firm of consulting engineers Frank Barber and Associates, and wrote a Report on comprehensive sewerage schemes for ... York, Ontario (1922). He was married to Mary Ellen Lewis, with whom he had three sons and a daughter.