Evaluation of accident black spots on roads using Geographical Information Systems (GIS):

Whilst the road accident situation is slowly improving in the high income industrialized countries, most developing countries such as Palestine, face a worsening situation. The continuous socio-economic changes over the years are causing an increasing demand for road transport. In addition to that, the deterioration of political situation is creating an absence of police authority over the roads, consequently more road conflicts develop including traffic accidents.

The small Palestinian traffic police force is trying with limited capabilities to monitor and control the traffic affairs in the Palestinian cities. With small number, limited sovereignty, lack of road accident-related data, the Palestinian police are struggling hard to do their job. Due to the political and security situation the Palestinian traffic police have a limited authority in most of the Palestinian towns and the connecting roads. However, the police force is more active in some cities in comparison with others.  

 Ramallah, the center of political and administrative activities of the Palestine National Authority (PNA), has experienced a steady increase in traffic during recent years, resulting in higher levels of congestion and corresponding increases in traffic. Many of these crashes were preventable through engineering changes and enforcement of existing laws. The use of accurate and timely information is critical for performing engineering studies, enforcement activities and budget planning. Some of these accidents result from human error and carelessness of the derivers or pedestrians. However, the probability of occurrence, and its severity, can often be reduced by the application of proper traffic control devices, and good roadway design features. The success or failure of such control devices and design specifications however, depends extensively upon the analysis of traffic accident records at specific locations. It has long been recognized that the most effective means towards accident reduction lies in a systematic and scientific approach based on the use of accurate and reliable traffic accident data.

 The available un-computerized police reports are covering just a limited part of the reported accidents, the contents of the report is insufficient to be used in studying the factors affecting the number of the accidents, and if available there is no specific locations are given which might help in the application of the GIS (Geographic Information Systems) technology in identification of these black spots. Road safety can only be improved when we understand the causes and consequences of road accidents/collisions. Analyzing the causes and consequences of collisions are important to work out remedial measures. Therefore, there is a real need to keep a database that should be planned, designed and implemented according to new standards and tools that include GPS and GIS.

The GPS technology will enable the traffic police to map locations of accidents easily, quickly and accurately to be fully integrated with the GIS technology. Using GIS will facilitate the integration of both the geographic location data and other important accident related data such as time, main cause,  road conditions, vehicle conditions and driver.

What are other benefits that the police can get from the application of GIS?

• Mapping traffic information rather than providing it in spreadsheets.

• Visualization of the results analyses such as color coding the accident according to different criteria which enables classification and characterization of high accident-potential locations according to parameters such as: large number of pedestrian’s accidents, locations with a large number of accidents due to speeding, etc. and then planning police operations, accordingly.

• Temporal analyses such as time pattern hunting and period comparison by color-coding accidents according to year/time of year in which they occurred, and investigating the migration of accidents from one location to another.

• To analyze accidents, external data can be integrated into the map, such as traffic volumes, location of traffic lights, road works, etc. This type of analysis enables one to determine whether a particular phenomenon exists or not in a given situation. For example, the location of a road accident involving children can be integrated with the location of schools in the vicinity.

• The results of this project might be used to support operational decision-making process. For example, in case of positioning automatic cameras to enforce speed limits. One of the means that could be used to determine where the cameras will be positioned is the mapping of road accidents caused by excessive speeding on the network of roads. Roads which have a higher percentage of such accidents, both quantitatively and in terms of severity, should be allocated more resources. Examining night time accidents may point to the need for additional lighting on particular roads, etc.

• Color-coding road accidents involving aged citizens or children highlights locations where public education and training must be focused to raise public awareness.

• The use of GIS would ease the work of geo-referenced accident data. Proper and accurate spot maps can be established. Moreover, accident data can be tied with other spatial data such as road characteristic and intersection geometry, to cover a full - range of analysis.