A moderate to higher speed corridor for vehicular and active transport movement functions that serves as a distinctive formal corridor in its urban context.
These corridors are important for travel within metropolitan areas at a lower speed than motorways. Access to the corridor is restricted, with junctions generally spaced 1km or more apart. Junctions tend to be intersections rather than separated interchanges, but high traffic volumes and widths make these corridors suitable for pedestrian bridges and separated paths.
Road user space (both spatial and temporal) is highly contested. When designing new primary arterial roads for greenfield areas, there is a risk that in attempting to cater for all road users, the road width will be increased. Very wide carriageways (40m or more) are more difficult for people to walk across, may encourage higher vehicle speeds, and may deter walking, cycling or use public transport from using the road.
Throughout the design process, you need to refer to the strategic intent for the road user space and consider the needs of all users. There may be opportunities to reduce the road width, for example, by reallocating road user space to higher capacity modes, sharing space, using temporal reallocation of space or priority, or by redistributing the network for some transport modes.
Drawings
Section
Principal arterial road section.
Plan
Principal arterial road plan.
Contextual characteristics
Situated at the edges of urban areas, to support growth and change
Cater for through-movement of people driving freight and service vehicles, people travelling in private vehicles, people using rapid bus services and people walking and riding
Usually consist of two vehicle lanes in each direction, often with space for a third reserved in a wide median
Include provision for active transport in verge areas
May include dedicated bus lanes
Physical characteristics
Typical reserve: 35–60m
Access restricted to intersections or interchanges, with no direct access to the corridor usually achieved through adjacent land-use controls
Car parking not permitted
Lane widths cater for vehicles of all types including freight
Design elements include shared or separated paths on at least one verge, large setbacks from adjacent land uses, wide corridors, trees where they are able to be located safely, utilities.
Issues and opportunities
Issues
Where situated between places where people live and their desired destinations, avoiding barriers that discourage active transport journeys
Where located close to residences, workplaces or schools, addressing potential noise impact and air pollution
Due to being located far from areas of high place intensity, bus stops along their length tend to be inaccessible
The speed limit and relatively high proportion of heavy vehicles may make the environment hostile to walking and cycling
Tree planting opportunities may be contested where there are conflicts with utilities or maintaining safety for people using vehicles
People travelling or transporting goods on these roads expect their trips to be direct, safe, reliable and conducted in the shortest reasonable time, but congestion and inadequate wayfinding can result in stressful, high-speed environments
Opportunities
When located in greenfield areas, allowing existing landscape character to be identified and incorporated into the corridor
As part of a well-designed transport network, facilitating efficient movement of people and goods between areas of high place value
Where coordinated with adjacent land-use planning:
supporting the needs of enterprises which depend on movement of goods and services
at creeks and in deep cuttings, incorporating additional cross-corridor connectivity for people walking and cycling