Central Motorway Junction

The Central Motorway Junction or CMJ, best known as Spaghetti Junction, is the intersection of New Zealand State Highways 1 and 16 south of the city centre of Auckland City, Auckland, New Zealand. It is multilevel structure (at least three traffic lanes crossing above each other in several locations) which has been described as a "fiendishly complicated, multi-layered puzzle of concrete, steel and asphalt" which carries around 200,000 vehicles a day." [http://www.nzherald.co.nz/topic/story.cfm?c_id=309&objectid=10413646 Spaghetti Junction comes to the boil] " - "The New Zealand Herald", Monday 04 December 2006]

The central motorway junction forms the intersection between the three major motorways of Auckland (Auckland Northern Motorway (1), Auckland Southern Motorway (1), and Northwest Motorway (16)), and provides access from these routes to the city centre. It is principally located in a series of gullies to the south and east of the CBD and in cuttings to the west.

It has somewhat of a hybrid function, falling between a typical ‘X’ interchange and ring road around the city centre. However all linkages are direct and there is no separate ring road as such. The interchange and associated structures encircles the Auckland CBD on three sides, the Auckland waterfront to the north forming the fourth 'border' of central Auckland.

History

Designed in the 1960s, and with most of its links built in the 1970s, [ [http://cmi.transit.govt.nz/html/cmi/history.htm History - Central Motorway Junction] (from the Transit New Zealand 'Central Motorway Improvements' project website. Accessed 2008-06-06.)] the junction was a major project in a scheme that forced over 50,000 people to move from the area when the central motorway network was constructed, with major effects on the nearby Karangahape Road shopping area.Fact|date=June 2008

The junction was substantially extended (or in a sense, finally completed) in the 2000s, with the final links opened to traffic in December 2006. During the duration of this NZ$208m project, the existing motorways had to be closed several hundred timed during nightime (with traffic rerouted over local roads).

Connections

The Central Motorway junction provides direct motorway-to-motorway links between the following four routes radiating from the city centre:

* Auckland Northern Motorway (SH1) to/from North Shore City via Auckland Harbour Bridge
* Auckland Southern Motorway (SH1) to/from Manukau City and
* Northwest Motorway westbound (SH16) to/from Waitakere City
* Northwest Motorway eastbound (SH16) to/from Ports of Auckland and eastern suburbs

The last of these links (Northwest Motorway eastbound to Auckland Northern Motorway northbound) officially opened on December 19, 2006, marking the full completion of the junction. Plans have now shiffted further north, with the proposed tunnel at the Victoria Park Viaduct being the last of a set of three major motorway projects in the area.

In addition, the CMJ also includes the primary dedicated city exits from SH1 and SH16 to downtown, Grafton Gully (being the first of the three large motorway projects, and containing the section of the Northwest Motorway between the Upper Queen Street bridge and The Strand in Parnell, and the Auckland Southern Motorway between Symonds Street exit and The Strand), with some five other pairs of ramps giving access to the central area.

An interesting structure of note is the area underneath Karangahape Rd, where some 19 lanes of traffic forming 9 distinct links pass through a very constrained cutting under the Karangahape ridge on a multi-level structure.

;Alternative routes

The other two major motorways under construction in Auckland, the 'South-Western' and 'Upper Harbour' motorways will form a continuous link in the west of the city between SH1 in the south at Manukau with SH1 in the north at Albany. The main goal of this route is to provide an alternative north-south route in the west that bypasses the central area and avoids the often congested central motorway junction.

ee also

*Grafton Gully
*Transport in Auckland
*Victoria Park Viaduct

References

External links

* [http://cmi.transit.govt.nz/html/cmj/home.htm Central Motorway Junction] (Transit New Zealand's project website)
* [http://www.aucklandmotorways.co.nz/cmjcomplete.html CMJ Complete] (CMJ entry on Auckland Motorways, a private website)