State Highway 18 (New Zealand)

State Highway 18
Route information
Maintained by NZ Transport Agency
Length	14 km (8.7 mi)
Major junctions
From	SH 1 Northern Motorway, Meadowood, North Shore City
To	SH 16 Northwest Motorway, West Harbour, Waitakere City
Location
Country	New Zealand
Primary destinations	Greenhithe, Hobsonville
Highway system
New Zealand state highways Motorways and expressways List
← SH 17 → SH 20

As of early 2010, large parts of State Highway 18 remain a standard, mostly rural highway.

State Highway 18 is a State Highway linking North Shore City and Waitakere City in Auckland, New Zealand. It is the northern part of the Western Ring Route. State Highway 18 formerly ran along the Coatesville Riverhead Highway, further north than its current position.

Route

As of 2008, State Highway 18 begins at the Northern Motorway as a dual carriageway road. Heading west on Upper Harbour Highway, after two kilometres it becomes a motorway at the Albany Highway interchange. This four-lane section of motorway opened in December 2007, and bypassed the single carriageway Upper Harbour Drive. The motorway heads south-west, crossing the upper reaches of the Waitemata Harbour over the Upper Harbour Bridge. The motorway ends at Buckley Avenue, and State Highway 18 follows the single carriageway Hobsonville Road. State Highway 18 runs north of the suburb of Hobsonville, before meeting State Highway 16 at the end of the Northwestern Motorway.

Upper Harbour Motorway

Upper Harbour Motorway
Location	Cuthill, Albany Highway Interchange – Hobsonville, Buckley Ave
Length	6 km (3.7 mi)
Existed	2007–present

The Upper Harbour Motorway is the name of the motorway section of State Highway 18. The first section opened in December 2007, and the second section, west of the first section, is likely to open in April 2011, ahead of its scheduled opening in 2012.

The Upper Harbour Motorway is currently six kilometres long with four junctions (including termini).

Interchanges

Territorial authority	Location	Exit	Destinations	Notes
Terminates onto Upper Harbour Highway at Albany Highway interchange
North Shore City		2	Albany Highway
		4	Greenhithe Road	Eastbound exit and westbound entrance
		6	Tauhinu Road	Westbound exit and eastbound entrance
Upper Harbour Bridge
Waitakere City		8	Squadron Drive	Currently at-grade. Will be upgraded to grade-separated interchage (westbound exit and eastbound entrance) on opening of extension west in 2011.
Currently terminates onto Hobsonville Road at Buckley Avenue
Waitakere City			Brigham Creek Road	Opens 2011
			Trig Road	Opens 2011 Westbound exit and eastbound entrance
	Westgate		Hobsonville Road Hobsonville	Opens 2011 Westbound exit and eastbound entrance
From 2011, terminates onto SH 16 Northwest Motorway southbound at Westgate

See also

• List of New Zealand State Highways