Western Line Duplication (Auckland)

The Western Line Duplication was a major component of Project DART, representing 70 per cent of the entire DART budget, approximately $420 million.

The duplication was delivered in stages across three years enabling progressive improvements to service frequency and reliability on the Western Line.

The various elements of the duplication project were (by completion date):

  • June 2007: Titirangi to Henderson; 7.5kms, 4 stations;
  • June 2008: Henderson to Swanson; 5kms, 3 stations;
  • April 2010: Newmarket to Boston Rd; 1km, 1 station;
  • June 2010: Avondale to Titirangi Rd; 3km, 2 stations.


Additionally 15 level crossings were upgraded and 2 level crossings removed.

A major element of the double‐tracking project was the duplication and lowering of the stretch of track through New Lynn into an 860m‐long, 8m‐deep rail trench.

The trench eliminated two busy level crossings and added two brand new bridges to make getting around the busy New Lynn town centre easier than ever.

The trench is the catalyst for a major redevelopment project planned by Waitakere City Council.

Another significant element was the duplication of just over one kilometre of track between Kingdon Street and the old Boston Rd Station. The project was completed in early April 2010.

The relatively short section of single track was a complex undertaking. The rail corridor had to be widened from 5m to 13m to make way for a second track, and the volcanic rock which runs through the area presented a major challenge.

The Khyber Pass Rd and Park Rd rail overbridges were progressively rebuilt in stages and the new Grafton Station built beneath them, with accesses from both sides of Khyber Pass Rd and Park Rd.