On 18 July 1909, the Ministry of Labour gave permission for surveying, which started on 8 August. The Railway Board send a proposal for a plan for the Rauma Line to the ministry on 23 May 1910, which was passed by parliament on 20 July. However, the vote did not include any allocation of money. Additional surveying started on 18 August 1911 and was led by W. Sandberg. This time two alternatives were to be surveyed, one with a maximum gradient of 2.6 percent, and one with 2.0. On 29 June, the government approved a concession for the line to be built as a private railway. The final plan for construction was presented by the Railway Board to the ministry of 17 June 1912, and was passed by parliament on 27 July.