Wittenoom was widowed in October 1919. From the early 1920s he lived in Albany, Western Australia, where he invested in property including several hotels, and became director of WA Woollen Mills. On 17 September 1923 he married Constance Patricia Hanrahan, with whom he had two sons and a daughter, Jacqueline (1927–2016), who married the Irish racehorse trainer Vincent O'Brien.[1] He became active in public affairs, serving as mayor of Albany Municipal Council from 1923 to 1931 (with a brief break in 1926), and again from 1940 to 1952. On 22 May 1928 he was elected to the Western Australian Legislative Council for the South-East Province. He held the seat until the election of 11 May 1940, when he was defeated by Hugh Roche. In later life he retired to Claremont, where he died on 18 September 1969. He was buried in Karrakatta Cemetery.