Super two
Encyclopedia
A super two, super two-lane highway or wide two lane is a two-lane surface road
built to high standards, typically including partial control of access, occasional passing lane
s and hard shoulder
s. It is often built for eventual conversion to freeway or at least divided highway
status once traffic volumes rise.
, the term wide two-lane is used by the National Roads Authority
in the planning of routes using such a road type. In policy documents, the designation WS2 is used.
Wide two-lane roads are common on national roads; both on less important but medium-capacity routes, and on more important routes not yet upgraded to dual carriageway
or motorway. Wide two-lane roads in the Republic generally have hard shoulders and are undivided single carriageway
. Grade separation
of junctions has been used on some schemes—for example the N20
bypassing Croom. Most wide two lane roads are wide enough that one can overtake without crossing the center line, if a vehicle in front pulls into the hard shoulder (the carriageway including hard shoulders is 15-17 metres wide ).
Many future national road schemes in the Republic will use 2+1 road
s or 2+2 road
s , as opposed to wide two lane which is considered to better suit lower capacities than that catered for by 2+1 . Wide two lane, if finished to particularly high quality, with grade separated interchanges, has been shown to lead to a false sense of security (from the apparently high speed road) and more dangerous driving (due to the carriageways not being separated) .
WS2 is also the term used in the UK for a wide single carriageway.
Pavement (material)
Road surface or pavement is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway. In the past cobblestones and granite setts were extensively used, but these surfaces have mostly been replaced by asphalt or concrete. Such...
built to high standards, typically including partial control of access, occasional passing lane
Passing lane
A passing lane or overtaking lane is the lane on a multi-lane highway or motorway closest to the center of the road ....
s and hard shoulder
Shoulder (road)
A hard shoulder, or simply shoulder, is a reserved area by the verge of a road or motorway. Generally it is kept clear of motor vehicle traffic...
s. It is often built for eventual conversion to freeway or at least divided highway
Divided Highway
Divided Highway is a compilation album by American rock band The Doobie Brothers, released in 2003. . All tracks are taken from the albums Cycles and Brotherhood .-Track listing:...
status once traffic volumes rise.
Wide two-lane
In IrelandRepublic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...
, the term wide two-lane is used by the National Roads Authority
National Roads Authority
The National Roads Authority is a state body in the Republic of Ireland, responsible for the national road network. The NRA was established as part of the Roads Act 1993 and commenced operations on 23 December 1993 in accordance with S.I. 407 of 1993.County councils remain responsible for local...
in the planning of routes using such a road type. In policy documents, the designation WS2 is used.
Wide two-lane roads are common on national roads; both on less important but medium-capacity routes, and on more important routes not yet upgraded to dual carriageway
Dual carriageway
A dual carriageway is a class of highway with two carriageways for traffic travelling in opposite directions separated by a central reservation...
or motorway. Wide two-lane roads in the Republic generally have hard shoulders and are undivided single carriageway
Single carriageway
A single carriageway is a road with 1, 2 or more lanes arranged within a single carriageway with no central reservation to separate opposing flows of traffic. Two-lane road or two-lane highway are single carriageway with one lane for each direction...
. Grade separation
Grade separation
Grade separation is the method of aligning a junction of two or more transport axes at different heights so that they will not disrupt the traffic flow on other transit routes when they cross each other. The composition of such transport axes does not have to be uniform; it can consist of a...
of junctions has been used on some schemes—for example the N20
N20 road
The N20 road is a national primary road in Ireland, connecting the cities of Cork and Limerick. Buttevant, Croom, Charleville, Mallow and Blarney are major towns along the route...
bypassing Croom. Most wide two lane roads are wide enough that one can overtake without crossing the center line, if a vehicle in front pulls into the hard shoulder (the carriageway including hard shoulders is 15-17 metres wide ).
Many future national road schemes in the Republic will use 2+1 road
2+1 road
2+1 road is a specific category of three-lane road, consisting of two lanes in one direction and one lane in the other, alternating every few kilometres, and separated usually with a steel cable barrier. Traditional roads of at least width can be converted to 2+1 roads and reach near-motorway...
s or 2+2 road
2+2 road
A 2+2 road is a specific type of dual-carriageway being built in Ireland and Sweden, consisting of two lanes in each direction separated with a steel cable barrier. They do not have hard shoulders. Junctions are at-grade roundabouts and minor roads cross under or over the mainline without...
s , as opposed to wide two lane which is considered to better suit lower capacities than that catered for by 2+1 . Wide two lane, if finished to particularly high quality, with grade separated interchanges, has been shown to lead to a false sense of security (from the apparently high speed road) and more dangerous driving (due to the carriageways not being separated) .
WS2 is also the term used in the UK for a wide single carriageway.