Stephens came to New Zealand as First Chief Assistant of the surveying staff to Frederick Tuckett Esq on the New Zealand CompanyNelson Preliminary Expedition in September 1841. He arrived near present-day Motueka on 9 October 1841 on the Whitby. The New Zealand Governor Captain Hobson had told the New Zealand Company that it could only found a settlement in the vicinity of Blind Bay in accordance with an agreement reached with local Maori. On 9 October Captain Wakefield, Tuckett, Stephens, and their guide a Mr Moore landed at Kaiteriteri and discussed possible alternative locations with the local Maori. Apparently the local Maori omitted to mention Nelson haven as they wanted the settlement constructed near their pa site. It was another two weeks before the New Zealand Company discovered Nelson haven and a further week before Wakefield decided to make it the place of settlement. Stephens assisted in surveying Nelson's town acres, as well as the Takaka and Aorere Valleys. For much of his time in the Province he lived at Riwaka. His neighbours were a native couple, Mary and Etani, who were on friendly terms with his family. In January 1843 he noted:"Oh! How do I blush for my countrymen, when I write that our fears for the safety of ourselves and property are not from the natives, but from the gangs of bad white men who now infest the country." He was appointed a Magistrate in Motueka in 1843. Stephens resigned in 1844 to take the place of Chief Surveyor for the District when Tuckett resigned. During his time in Nelson Stephens kept meteorological records and provided 11 years of these to Captain Drury RN, HMS Pandora prior to his demise. In 1845 he explored Lake Rotoiti and the Buller Valley, constructed a water-powered flour mill and surveyed a demarcation line between disputed lands at Wakapuaka. But in mid-1845 Stephens suffered from an outbreak of abscesses and ulcers, which were to plague him for the rest of his life. In 1848 he wrote to his sister saying that his ‘miserable affliction' had left him a mental and physical wreck and that he had been unable to walk without great pain for nearly three years. The affliction stopped him working as a surveyor. In the summers between 1848 and 1853 Stephens and his wife lived at a beach camp at Stephens Bay, Kaiteriteri. He became the Member of Parliament in the 1st Parliament for the Town of Nelson from 19 June 1854, when he replaced William Travers, who had resigned on 26 May 1854 to contest the Waimea seat. Since 19 August 1854, Stephens also represented the District of Motueka on the Provincial Council. After a period of lingering illness he died on 26 June 1855, and the seat was left vacant until the election of the second Parliament. His wife Sarah sold their property and returned to England.
