German Model

Relieving congestion on the federal highway network through multimodal passenger transport services

The Federal Transport Infrastructure Plan (BVWP) 2030 has as specific goals to include reducing congestion on the federal highway network and increasing passenger and freight rail capacity. At the same time, the Federal Transport Infrastructure Plan and the National Platform for the Future of Mobility, formulate, among other things, the future goal of a "largely greenhouse gas-neutral and environmentally friendly transport system”. In order to meet both goals, motorized private vehicle trips shall be shifted to more sustainable modes, which would in the end reduce transport emissions.

The objective of this project is to identify multimodal options of long-distance passenger travel in order to relieve the federal highway network and evaluate their potential to meet the Federal Government’s transport and environmental policy goals. Six strategies to reduce individual private vehicle long-distance trips were tested: (1) improvement of access/egress to long-distance rail, (2) improvement on the long-distance bus service, (3) Deutschland-Takt (nationwide integrated regular interval timetable), (4) implementation of tolls, (5) combination of “pull” (transit) strategies (1+2+3), (6) combination of “push” and “pull” (toll) strategies (1+2+3+4). The evaluation of the measures included transport, environmental and social indicators.

Given that the measures are not yet implemented, traffic simulations were used to estimate the effect of the strategies. The approach used two models: an agent-based model and an aggregated model. For this project, we generated the synthetic population of Germany for the year 2030. For each agent, long-distance travel demand was simulated using a newly developed travel demand model ALDTO (Agent-based Long-Distance Transport Orchestrator). The model was estimated and calibrated using the German Household Travel Survey (Mobilität in Deutschland, 2017). The trip lists were assigned to the network using MATSim, for the agent-based approach, and SUMO, for the aggregated approach.

The results provide a better understanding of potential strategies and policies to reduce transport emissions and improve the quality of service on the Federal Highway Network, while minimizing social impacts. The combination of “push” and “pull” strategies provided the best results. Applying tolls to the federal highway network reduced more effectively the share of private vehicles but shifted traffic and congestion problems to the local network. Combining this measure with all transit improvements mitigated the most negative impacts of tolls, such as slight increase on transport emissions and higher inequality between high- and low-socioeconomic status households. However, the results were not close to the targets. There is still potential for further reductions in emission levels through other long-distance measures, such as restrictions on air travel or higher vehicle operating costs, which should be also combined with short-distance measures to achieve the overall goal of a largely greenhouse gas-neutral transport system. r