More crashes occurred in the Melbourne metropolitan area (60%) than in the rest of the study area (40%). For those crashes in the metropolitan area, the land use adjacent to the crash site was most commonly urban residential (see Table 6.1). For those crashes in the rest of the study area, the most common adjacent land use was rural farmland.
Table 6.1. Percentages of crashes according to land use adjacent to the crash site.
Adjacent land use Metropolitan area (n=76)
Table 6.2 summarises the type of road on which the crash occurred. The categories were based on Melway Directory markings for the Melbourne metropolitan area and the VicRoads Country Directory markings for the rest of the study area. Most crashes occurred on highways, with fewer crashes occurring on major roads and minor roads.
When a crash occurred at an intersection, the road type was coded with respect to the first-mentioned road (it was unclear from some notifications the road on which the vehicle was travelling).
Table 6.2. Percentages of crashes which occurred on each type of road.
Road type Metropolitan area (n=76)
A larger proportion of crashes occurred on highways and a smaller proportion on minor roads in the metropolitan area compared to the rest of the study area (see Table 6.2).
Overall, 66% of the crashes occurred on undivided roads (58% of metropolitan, 77%
of rural). Most crashes in both areas occurred on two way undivided roads, although a somewhat larger proportion of metropolitan than rural crashes occurred on dual carriageways without service roads (see Table 6.3).
Table 6.3. Percentages of crashes according to road configuration.
Road configuration Metropolitan area (n=76)
Of the crashes in the study, 48% occurred where the speed limit was 100 km/h or greater (see Table 6.4). Not surprisingly, a higher proportion of rural crashes (82%) than metropolitan crashes (23%) occurred in these higher speed zones.
Table 6.4. Percentages of crashes according to speed limit at the crash site.
Speed limit (km/h)* Metropolitan area (n=76)
* Includes temporary speed limits because of roadworks.
6.3 ROAD GEOMETRY
Information about horizontal alignment was available for 119 crash sites. Where the recorded radius of the curve was greater than 1000m, the road was deemed to be straight. Where it was known, 32% of metropolitan crashes and 40% of rural crashes were on curves. Table 6.5 shows that the most common curve radii were 100 to 200m and between 600m and 100m.
Table 6.5. Curve radius for crashes on curves.
Curve radius (m) Number of cases Percent of cases Less than 100 5 12
6.3.1 Type of intersection
Overall, 20% of the crashes in the study occurred at intersections. These comprised 29% of crashes in the metropolitan area and 8% of rural crashes. Table 6.6 shows that T-intersections were the most common types of intersections for both
metropolitan and rural crashes. In almost all of these crashes, the vehicle was travelling on the continuing leg of the T-intersection.
Table 6.6. Percentages of intersection crashes which occurred at each type of intersection.
Type of intersection Metropolitan area (n=22)
For about half of the crashes, there was one lane only in the direction of travel. This was more common outside the metropolitan area (see Table 6.7).
Lane configuration at the site of the crash was recorded. Table 6.8 shows that the number of lanes was not changing at most crash sites. Exit lanes were the most common feature where the number of lanes was changing in the metropolitan area.
Road markings were present at about 90% of the crash sites (91% of metropolitan, 88% of rural). There were raised reflective pavement markers at 22% of the crash sites (18% metropolitan, 28% rural).
Table 6.7. Percentages of crashes according to the number of lanes in the direction of travel.
Number of lanes Metropolitan area (n=76)
Table 6.8. Percentages of crashes according to lane configuration. There can be more than one per crash, so the percentages sum to more than 100%.
Lane configuration Metropolitan area (n=76)
There was a median present at the site of 39% of crashes (46% of metropolitan, 29%
of rest of study area). Table 6.9 shows that most medians comprised paved, gravel or low level landscape (with or without trees).
Table 6.9. Percentages of crashes which occurred at sites with each type of median.
Type of median Metropolitan (n=35)
Paved, gravel or low level landscape
26 13 22 Paved, gravel or low level
landscape with trees
For the seven sites where there were service lanes, the type of outer separator was coded. The outer separators were all coded as being paved or gravel or low level landscaping. About half of them had trees.
There was a side drain present for 57 crashes (45%). Information about the presence of a side drain was absent for 2 crashes (2%). The side drain was considered to be navigable in 39 cases.
Kerbs were present at the sites of 44% of crashes (68% of metropolitan, 8% of rural).
Approximately half of the kerbs were mountable and half were barrier kerbs.
6.6 TRAFFIC CONTROLS AND LOCAL AREA TRAFFIC MANAGEMENT DEVICES
Traffic controls were present at the site of 13% of crashes (18% of metropolitan, 6%
of rural). Traffic control signals were the most common form of traffic control, followed by Stop signs and roundabouts (see Table 6.10).
Table 6.10. Percentages of crash sites by type of traffic control present - sites with traffic controls present only.
Traffic controls present Metropolitan area (n=14)
Local area traffic management devices were present at eight crash sites (6%), all of which were in the metropolitan area. Five of the eight LATMs were roundabouts.
6.7 THE ROAD SURFACE
Only 3% of crashes occurred on unsealed roads (see Table 6.11). Most road surfaces were coded as asphalt. Chip seal was somewhat more common and slick bitumen less common outside of the metropolitan area.
The surface coarseness of the road pavement was coded as “medium” for most crashes. Coarse pavements were somewhat more common outside the metropolitan area (see Table 6.12).
Table 6.11. Percentages of crashes according to the road surface.
Road surface Metropolitan area (n=76)
Table 6.12. Percentages of crashes according to the coarseness of the road surface.
Surface coarseness Metropolitan area (n=76)
Mud, oil or loose material on the road surface was present for only a small number of crashes overall, but was present for 10% of rural crashes (see Table 6.13).
Table 6.13. Percentages of crashes according to the cleanness of the road surface.
Surface cleanness Metropolitan area (n=76)
Surface irregularities such as pot holes, pit lids and drainage grates, deformed
pavement and sudden changes in the road surface were reported for very few crashes.
6.7.1 Road shoulder
The road had a shoulder for 62% of the metropolitan crash sites and 96% of the rural crash sites. At metropolitan crash sites, 49% of shoulders were sealed compared with 20% of shoulders at rural crash sites (see Table 6.14).
Table 6.14. Percentages of crashes according to the material of the shoulder - crashes where there was a shoulder present only.
Surface of shoulder Metropolitan area (n=47)
The presence of roadside objects was coded for each crash location. Trees were the most common roadside object in the metropolitan area and the rest of the study area.
This was followed by poles and fences in the metropolitan area and fences and poles in the rest of the study area (see Table 6.15).
Table 6.15. Percentages of crashes according to roadside objects present. More than one roadside object may be coded at a site.
Roadside objects present Metropolitan area (n=76)
The road was wet for 37 crashes (29%). Half of the crashes occurred when it was dark (see Table 6.16). There were no street lights at the site of 32% of the crashes in the metropolitan area and 86% of crashes in the rest of the study area.
Glare from oncoming headlights was considered to be a potential problem in 5 cases (4%). In 2 cases glare from the sun may have reduced visibility.
Table 6.16. Light conditions at the time of the crash.
Light conditions Number of crashes Percent of crashes Percent of daytime crashes
Sunny/bright sunlight 25 20 39
Overcast/cloudy 30 24 47
Dusk or dawn 7 6 11
Dark 63 50
Unknown 2 2 3
Total 127 100