Dunedin-Waitati Highway is relatively steep and winding, traversing part of the Silverpeaks range of hills. It begins a short distance north-west from where the two main parts of Dunedin's central business districtone-way street system combine near The Gardens Corner with a pair of bridges over the Water of Leith. The highway connects with Bank St and George St then climbs Pine Hill Rd to the northern Dunedin suburb of Pine Hill. From there it follows the northeastern side of the Leith Valley, then crosses the headwaters of the Leith before traversing the Leith Saddle and taking a roller-coaster-like course to the valley of the Waitati River, then to Waitati. Together with The Kilmog, a hill north of Waitati, this is one of the two most notable hill sections of State Highway 1 south of Christchurch.
'Motorway' status and access
Dunedin–Waitati Highway was officially designated a motorway when it opened on 14 December 1957 and is still colloquially referred to as such. "Motorway" signage was removed and the road lacks any indication of its former status other than "No Cycling/No Pedestrians" signs at Pine Hill and Waitati Valley. Apart from occasional overpasses, it does not resemble a freeway or motorway, rather a two-to-four-lane undivided limited-access road, although cyclists and pedestrians are allowed on the northern section. Dunedin-Waitati Highway is a highway in terms of traffic regulations, while the land corridor is designated motorway under the New ZealandGovernment Roading Powers Act and town planning rules. There are occasional private property accesses along the 15 km length and two at-grade intersections: one at the Leith Saddle summit, with Leith Valley Road and Waitati Valley Road, the other at the lower end of Waitati Valley Road. Intersecting roads all have low traffic volumes and are unsealed. All other road crossings are grade separated on bridges with no road connections, at Maxwellton Street, Leith Valley Road, Dryden Road, and Pigeon Flat Road; the last of these is the only bridge north of the saddle.
Improvements
Several parts of the highway were realigned or widened around 2000, most notably between the Pigeon Flat Overbridge and the start of the Waitati River floodplain.
Leith Saddle
signalled in 2004 its long term intention was to re-align SH1 in the vicinity of Leith Saddle, which would require some removal of old-growth forest The forest here features a species of Libocedrus, variously called Pahautea, Kaikawaka or New Zealand cedar, Libocedrus bidwillii, which is unusual in this region of New Zealand. Transit New Zealand stated in 2004 that Leith Saddle has 250% more crashes than average for the New Zealand state highway network and that the accident rate increased by 50% in the ten years to 2004. They said realignment here would reduce traffic delays, fuel use, crashes, and emissions of carbon dioxide and carbon monoxide.
