South Road, also known as Main South Road, is a major north–south conduit in Adelaide and Fleurieu Peninsula in South Australia. It is one of Adelaide's most important arterial and bypass roads. The northern part of South Road contributes the central component of the North–South Corridor, a series of road projects under construction or planning that will eventually provide a continuous expressway between Old Noarlunga and Gawler.
History
South Road of today was until the 1970s known by a string of names: Shillabeer Avenue, Government Road, John Street, Taylors Road., Fisher Terrace, and South Road from Anzac Highway southwards.
South Road suffers from traffic congestion due to its importance as one of Adelaide's main arterial roads and bypasses. Traffic has also increased in line with the growth and development of Adelaide's southern suburbs. An overpass was built over Cross Road and the Noarlunga railway line between 1982 and 1984 to reduce a major bottleneck. The State government completed the "Gallipoli Underpass" under Anzac Highway, and an overpass of the Adelaide-Glenelg tramway, in 2009 and 2010. The underpass model used is a diamond interchange. In November 2005, the Royal Automobile Association released its recommendations to the South Australian government in regards to the road network. South Road was found to be the poorest road in the state, registering a 2/10 on the RAA's scale. The recommendations given included $6 billion of funds to upgrade the roads of South Australia – with $1.5–2 billion to be spent on South Road alone. The RAA's plan for the road included a 6 km tunnel from Port Road all the way to the Anzac Highway underpass and over/underpasses at six other major intersections and two rail crossings. On 18 August 2007, Prime Minister John Howard announced that South Road was to be included in the AusLink National Road Network, and also pledged $1 billion in funding for the project between 2007 and 2020. In October 2009, both the Premier of South Australia and the Prime Minister released plans for the South Road Superway — a 3–4 km section of elevated freeway running from the Port River Expressway to the intersection of Regency Road at a cost of $800 million. The project started in 2010 and was completed in early 2014. The elevated part provides separation at Grand Junction Road, Cormack Road, and the Dry Creek-Port Adelaide railway line. Two further sections were identified and funded for upgrade following the 2013 Australian federal election. The first of these was the Darlington Upgrade addressing the section from the northern end of the Southern Expressway to provide a free-flowing route under the intersections with Flinders Drive and Sturt Road to the Ayliffes Road intersection. The Torrens Road to River Torrens lowered motorway addressed the major intersections with Grange and Port Roads, the Outer Harbor railway line crossing, and several minor road intersections. Both of these upgrades involved land acquisition to widen the road corridor, surface grade carriage ways on the edges, and a lowered central roadway carrying the free-flow traffic below the crossing routes. The Torrens to Torrens project was started in 2015, and opened to traffic in 2018. The scope of both sections was extended northwards. The initial plan for Torrens to Torrens did not include grade separation at Torrens Road which was later added. The initial plan for Darlington did not include grade separation at Ayliffes Road or Tonsley Boulevard. The Darlington upgrade is scheduled for completion n mid-2020. In January 2017, the Outer Harbor railway line level crossing was replaced in a grade separation project as part of the Torrens to Torrens project. In April 2017, reports emerged involving a confirmation by the State Government stating that South Road's upgrades used contaminated cement. The Torrens River to Torrens Road lowered motorway opened to traffic in late September 2018. An upgrade of Regency Road to Pym Street, the gap between the elevated South Road Superway and the almost-completed Torrens to Torrens project, was announced on 1 May 2018, to be jointly funded by the state and federal governments. The section includes three sets of traffic lights and several uncontrolled intersections with minor streets. A timeframe for completion was not announced at the same time, but was later announced to be expected in 2022.