Intersection - Delineation
Clear delineation is required at intersections to inform road users that there is an intersection present and to provide information about the types of manoeuvres that may occur.
In the worst case situation, road users may not realise that an intersection is present, and collide with other vehicles or road users, often at high speeds. Poor delineation may also result in late braking behaviour by road users who are required to stop, or wish to make turns. Improvements to intersection delineation can be made by making adjustments to, or installing new traffic islands, street lighting, linemarking and signs.
Linemarking deficiencies (such as unclear approach lane lines, and faded or missing Stop or Give Way markings) are easily and cheaply treated. Warning signs can be used to give drivers advance notice of an upcoming intersection. They are also cheap to install and particularly useful where the intersection is sub-standard. Median islands (or splitter islands) can be used on the approaches to intersections to improve the prominence of intersections (including by the provision of additional signs on median islands), and provide an additional benefit as they channelise traffic and may provide pedestrian protection if designed well. Improving street lighting at such locations should be also considered.
Delineation is important at critical locations such as the tip of traffic islands and gore areas. In addition to line markings, treatments include painting of kerbs, marker signs, and delineator posts. It is desirable to maximise the colour contrast between road surface and traffic islands. A possibility is to adopt a concrete surface of light colour for roads on asphalt.
- Reduction in intersection crashes.
- Reductions in speed.
- Awareness of the intersection is increased.
- Vehicles are directed to a clearer path through the intersection.
- Median islands (if used) can create a refuge for pedestrians crossing the road, thus reducing the likelihood of pedestrian/vehicle crashes
- Old linemarking should be properly removed (eg. by grinding) or it may remain visible and confuse drivers.
- Warning signs should be placed at sufficient distance from the intersection to ensure drivers have enough time to take necessary action (e.g. to slow down).
- Warning signs and median islands should not be located or designed in such a way as to be hazards.
The Star Rating Demonstrator is a freely available tool with the iRAP online software, ViDA. With the Star Rating Demonstrator, it is possible to explore the impact that this Safer Roads Treatment has on risk.
Treatment Summary
Costs | Low |
Treatment life | 1 year - 5 years |
Potential casualty reduction | 10-25% |