Pleasant Valley site, and one scheme at the Tamblyn's Orchard site. Initially Site No. 4 at Pleasant Valley, about upstream from Tamblyn's Orchard was favoured. Subsequent detailed design studies however found that Tamblyn's Orchard at Coal Creek where the river exited the Roxburgh Gorge near the town of Roxburgh offered the fullest possible head and thus the most power output, better tailwater conditions, the best access and would be closest to suitable locations for both construction and permanent villages. In March 1949 the government committed to building at Tamblyn's Orchard and plans were prepared to enable work on the diversion channel to start in June 1949. In October 1949 at the request of the Ministry of Works, Dr. John L. Savage - a former Chief Design Engineer of the United States Bureau of Reclamation - visited the site and provided advice on the proposed design options. While an earth dam was more suitable at the wider Pleasant Valley location after considering various options it was decided in October 1950 that due to the geology at Tamblyn's Orchard a solid-concrete gravity dam would be more appropriate. Another consideration was that the Ministry of Works and Development (MOW) had limited experience with the construction of earthen dams and its only engineers with the necessary experience were engaged on the Cobb Power Station. Many of the design decisions were based upon results from studies undertaken from 1949 to 1954 on a 1:80 scale model of the dam at the Department of Scientific and Industrial Research's Hydraulics Laboratory at Gracefield, Lower Hutt. Initially the project was known as the Coal Creek scheme but after the Geographical Board had been consulted the name Roxburgh was chosen as name of the power station in 1947. Construction Work commences on site The MOW was the government department responsible for designing and constructing the government power station in New Zealand. Though it was still unresolved who would be designing and building the dam and power station Fritz Langbein the engineer in chief of the MOW assumed that his organization would be undertaking the design and would at the least build the diversion channel. Therefore, he put in place plans to build a construction village and in July 1949 had the MOW commence work on the excavation of the diversion channel. This channel would eventually be long, wide and deep which required the removal of of material. By the