Road Management
Making informed decisions from location-based data.
This is an example of how vehicle accident data can be mapped with road network and speed data to inform road safety decision making, and policy change.
We are looking at the county of Oxfordshire in the heart of Britain, and taking a closer look at a specific section of the A34 and the A4142 Eastern bypass, where Oxfordshire County Council's have mapped vehicle accident data to identify accident hotspots.
Oxfordshire County overview
Oxfordshire County road network for our area of interest. Here we are looking specifically at stretches from the A34 - Dual Carriageway that runs to the west of the city of Oxford, and the A4142 - Dual Carriageway Eastern bypass.
Here we have the first of three maps that show points representing road accidents. Each point signifies the specific location along the A34 and A4142 Eastern Bypass roads where the accident happened.
Map 1 shows the road accidents categorised by their severity, ranging from Slight - Fatal.
By looking at the map we can identify accident hotspots and stretches of road where most fatal accidents have happened.
Map 2 shows the accidents categorised by their visibility conditions when the accident occurred.
There are 3 lighting categories that have been considered:
Daylight
Darkness - with streetlights
Darkness, unlit - no streetlights
You can see on the map that the majority of the road accidents have happened in the dark.
Map 3 shows these same road accidents but categorised by their speed in which the road accident occurred. Ranging from 20 - 70mph.
You can see from the map a lot of the accidents have happened when driving at 60-70mph.
The data shows that a great number of vehicle accidents have occurred on these two roads at 70mph. In order to lower the risk of future vehicle accidents, a new road speed limit has been enforced, changing the speed limits from 70mph to 50mph.
Swiping between the two maps below you can see where the 50mph speed limits have been introduced on the A34 and on the A4142 Eastern bypass, and you can compare the speed limit data with how many accidents were recorded at 60mph and 70mph. By reducing the speed limit similar accidents should in future be avoided.
When visualising the road network and the vehicle accident points, and categorizing them by speed limit, visibility, and severity, it becomes evident where there are accident prone areas and where a change in road management could be applied and be most effective.
This example demonstrates how location-based data can help you to prioritise and make good quality decisions based on evidence.
This story map has been created using the following data:
- Boundary-Line
- OS MasterMap Highways Network - Roads
- Oxfordshire County Council Vehicle Accident data
Further detail about these can be found on the OS website product pages.
The logo in the top left of this story map will take you to the main OS website homepage.
More story map examples like this once can be found in the More Than Maps site.
