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 at that time. It was not until the 1920s that significant campaigning for a replacement again prevailed on the government. In 1921-22 a feasibility study was conducted, including distances and estimated costs. Several routes were considered, including variations on previous ideas, but nothing more was done at the time; although a deviation of "about 5 miles 48 chain" (9 km) as the Wellington-Napier Line (Rimutaka Deviation) "running generally to the south-eastward of the existing line" was authorised by the Railways Authorisation Act, 1924. The new Labour government of 1936 announced its intention to proceed with the Mangaroa to Cross Creek