Central Motorway Junction Complete

Contents: History | The Projects: CMJ Northbound, North Western Links or CMJ Southbound | Urban Design | What Next?

Central Motorway Junction/Spaghetti Junction

Complete in 2006 @ $300m

The Central Motorway Junction or Spaghetti Junction is the meeting place of Auckland's three main motorways. This T style junction begun its design process in the 1950's and started construction in the 1970's. Up until 1989 more links were added, the last being the North Western link to the southern. The junction was never fully completed until now.

The junction is more than a meeting place of the three motorways, this is why congestion issues occur. Traffic from large employment and freight handling areas all link in to this junction. To make the job more complicated it requires complex bridge designs, interaction with city streets and detailed traffic analysis and modeling.

The CMJ Spaghetti Junction project has been investigated and put off since the early 90s. The project of improving the junction finally began in 2002 and was completed in December 2006.

Current Traffic Status (CMJ Right Now)

History

1955	1973	1990's
Present; (Simulated Image, One Link Incorrect)

The Projects

	Khyber Pass Bridge Widening The Khyber Pass Bridge which goes over Khyber Pass Road was originally seven lanes, or three lanes southbound, four northbound. To allow for two more lanes on each side a complex strategy was put in place to allow no disruption to traffic flow. First the middle section of the bridge was strengthened, then a thinner median barrier replaced the existing median barrier strip in the middle. Second the left and right sides of the bridge were strengthened, widened and opened to traffic and it made way for two more lanes. More Images
	Khyber to Gillies Ave Widening The section between Khyber Pass & Gillies Ave is the busiest section of roadway in the country, originally the layout was three southbound and four northbound lanes. Now the layout is five lanes each direction, totaling ten lanes. It includes two auxiliary lanes for Khyber to Gillies and vice versa, and space for another lane if needed in the future. To allow for the widening pushing back and strengthening the rock walls and widening the Maungawhau Road overbridge on both sides was necessary. More Images
	Gillies Ave On-Ramp Gillies Ave on-ramp is one of the busiest in the CMJ section, the project removed the merge with southern motorway. Now traffic has 500m to change lanes, and the lane is shared with the new Khyber Pass off-ramp (auxiliary lane[?]). More Images
	Khyber Pass Off-Ramp The Khyber Pass off-ramp has been designed to fit in with the Gillies Ave on-ramp auxiliary lane[?]. More Images
	Nelson Street Off-Ramp The Nelson Street off-ramp was shifted to the left side because its original layout on the right side was unsafe and not to motorway standard (i.e. causes traffic pattern issues). Currently the existing Nelson Street off-ramp remains as it is because it is costly to demolish. It will be used for emergency access or a possible ramp in the future. Before & After Images
	Northern Motorway to North Western & Port Before these connections were in place traffic had to drive through the CBD to access the ramps for the motorway. Now motorway to motorway connections have been established. More Info & Images
	North Western & Port to Northern Motorway Before these connections were in place you had to drive through the CBD to access the ramps for the motorway. Now motorway to motorway connections have been established. More Info & Images \| Ramp Signalling operates here
	City to Western Springs Widening Originally at three lanes wide the North Western Motorway has been widened to four lanes until the St Lukes off-ramp. Larger Image
	Hobson Street On-Ramp This was one of the first projects to be completed in the second stage of the CMJ upgrade, the original Hobson Street on-ramp had to merge with southbound traffic now it enters in its own lane. Before and After Images \| Ramp Signalling operates here.
	Grafton On-Ramp Due to the number of large vehicles using this on-ramp the on-ramp has been significantly extended to allow for easier merging. Ramp Signalling operates here.
	Khyber Pass On-Ramp The Khyber Pass on-ramp is the last on-ramp in the CMJ southbound direction and in close proximity with the Gillies Ave off-ramp, the upgrade of the Gillies Ave off-ramp tied in with the Khyber Pass upgrade giving the section an auxiliary lane[?] which makes merging easier. Ramp Signalling operates here.
	Gillies Ave Off-Ramp The Gillies Ave off-ramp now features an exit only lane and a split lane, it incorporates an auxiliary lane[?] with Khyber Pass on-ramp.

Urban Design

To minimise the sometimes drab hideous look of a motorway the CMJ project incorporated Urban Design (Urban design concerns the arrangement, appearance and functionality of cities, buildings and structures).

This Urban Design has made CMJ look like a work of art, with a New Zealand motif, incorporating Pōhutukawa imprints and other designs that match New Zealand into the concrete panels, new sculptures and utilising found objects into art.