Effectiveness of safety measures on rural roads in Bavaria

01 Jun 2017 Infrastructure
A safe road infrastructure ultimately has to be ensured at regional and local level. Previous DEKRA Road Safety Reports have referred multiple times to the outstanding role performed by the accident commissions. The Bavarian Ministry of the Interior, for example, reported on a range of positive experiences with tangible success: In a report published in 2011, the ministry described the effectiveness of road safety measures aimed at eliminating accident blackspots on country roads.
Since their founding in 2000, the 107 Bavarian accident commissions have been engaged in identifying accident blackspots on interurban roads (highways, main roads, state roads and some district roads) and eliminating them by introducing measures aimed at improving safety. This is now being followed by an analysis of their effectiveness (success monitoring) in order to identify any further potential for improvement. All the relevant information is recorded in a central database. This information includes specialist data and geodata relating to the road network and accident data collected by the police stations with electronic accident type maps. The accident commissions record other relevant information about accident blackspots and for documenting measures.
A detailed compendium has been prepared for documenting safety measures that have been implemented, how effective these measures were and how much they cost. Effectiveness (benefits due to fewer accidents) is indicated by means of a three-color system (green: optimum effect; yellow: partially effective; red: not effective). The figure shows an example of a summarized evaluation of measures implemented to reduce road accidents on longer stretches of roads in a total of 86 cases. In ten cases, for example, speed was limited only by a sign stipulating a speed limit (of 60 km/h, 70 km/h or 80 km/h depending on the local conditions). Although this was a low-cost measure, its effectiveness was considered optimal in less than a quarter of cases. In 25 cases, speed limits were subjected to intensive surveillance, which resulted in average annual costs of around €10,000. The effectiveness of this measure was considered optimal in around one third of cases. The most effective measure proved to be upgrading existing sections of roads or constructing new roads in line with the relevant standards. The effectiveness of this measure was considered optimal in more than 75% of the ten cases analyzed.
With average annual costs in excess of €50,000, however, this measure is the most expensive.
In total, improvements in road safety were observed in 83% of the detected accidents blackspots where evaluable measures had been implemented. 80% of the measures were considered effective in terms of cost and safety. Before the accident commissions were set up, the cost of accidents on non-urban main roads and state roads in Bavaria had fallen by 16% between 1991 and 2000. As soon as the accident commissions were set up, this trend increased significantly.
Between 2000 and 2009, there was a 37% reduction, which means that the annual decline in accident-related costs has more than doubled. In the accident blackspots identified and eliminated through various measures, accident-related costs fell by around eightfold compared with those on the rest of the road network. Since the launch of the accident commissions in 2000, the number of serious accidents – especially on non-urban roads – in Bavaria has declined significantly. The economic benefit of all the measures introduced outweighs their cost more than twelvefold.