Railway electrification in New Zealand Railway electrification in New Zealand Railway electrification was initially adopted by the New Zealand Railways in New Zealand for long tunnels; the Otira Tunnel, the Lyttelton Rail Tunnel and the two Tawa Tunnels of the Tawa Flat Deviation. Electrification of Wellington suburban services started with the Johnsonville Line and Kapiti Line out of Wellington from the 1930s. Auckland suburban services were electrified in 2014–15. Electrification of long distance services on the North Island Main Trunk (NIMT) dates from 1986, although KiwiRail is now considering diesel operation of the NIMT. New long tunnels e.g. the Rimutaka Tunnel and the Kaimai Tunnel
Rimutaka Tunnel made bigger." Transdev Wellington operates passenger services named the Wairarapa Connection between Wellington and Masterton via the tunnel five times a day each way Monday to Thursday, six on Friday, and twice a day each way on Saturday, Sunday, and public holidays. Excursion trains also go through the tunnel, such as railway enthusiast specials and trains to the Toast Martinborough festival. Steam-hauled excursions require diesel locomotives to provide motive power through the tunnel due to the danger from smoke in the tunnel's lengthy and confined conditions. From 2014 diesel locos hauling passenger trains in long tunnels were required to have