Wairio Branch - Operation

Operation

Freight trains off the Wairio Branch were largely industrial, and passengers were carried from Wairio to Invercargill from the line's opening until well into the 20th century. Due to decay of the old WR&CC line, the Railways Department stated that it would not permit its wagons to be used on the line after 31 December 1924, and thus the timing of the opening of the line to Ohai at the start of January 1925 proved to be fortuitous as it could carry traffic from the mines that had previously utilised the WR&CC route. Later in 1925 the Nightcaps Coal Company shut down operations and its railway extension was acquired by the Railways Department, which dismantled it in 1926.

The Ohai Railway Board used locomotives bought from the Railways Department as motive power - initially one C and two FA class locomotives, later replaced by an X class tender engine and a WAB class tank locomotive. Upon dieselisation in the 1960s, small diesel shunters such as a DSA class were used, and then a DJ class locomotive was employed. In the early 1990s the Ohai line was incorporated into the national network and the line beyond Wairio became known as the Ohai Industrial Line. The motive power used on the line from this stage was the same as that employed to haul the train from Invercargill. Presently, one train runs every weekday from Invercargill and return, arriving at Ohai at 9.30am and leaving two hours later. This service operates on Saturdays and Sundays when required. In June 2007, the Southland District Council adopted as part of the Otago Regional Land Transport Strategy a provision to upgrade the Ohai line and maintain it as a viable alternative to road for bulk freight.

On 15 May 2008 Fonterra and Eastern Coal Holdings reached an agreement to continue to rail coal from Eastern Coal's Takitimu mining operations in the Ohai/Nightcaps district to Fonterra's Clandeboye dairy factory. Under this new contract, approximately 120,000 tonnes of coal will be carried annually by the Ohai line. After infrastructural upgrades such as a new rail load-out system were undertaken, the contract came into effect on 1 September 2008; to fulfil it, trainloads of up to 550 tonnes of coal leave the Branch daily. In 2011, Kiwirail undertook a refurbishment of the line with a large re-sleepering and bridge strengthening projects to allow larger, heavier, containerised coal trains to operate, while allowing for an increase in speed. This work was completed in late 2012.