The BrennerLEC project was carried out in the context of a sensible area like the Alps with the objective of creating a holistic concept of “Lower Emission Corridor” (LEC) for the A22 highway. The project aimed to implement and validate a set of different dynamic policies that have the goal to provide a clear environmental benefit in terms of air quality, climate protection and noise abatement.
The BrennerLEC initiative has been conceived to address environmental concerns in the Alps region by establishing a ‘Lower Emission Corridor’ (LEC) along the Brenner highway. The project aims to significantly reduce air and climate pollution and minimize noise levels. It endeavors to strike a balance between environmental benefits, service quality, safety, and user acceptance. To achieve this, the initiative has planned extensive monitoring activities on different parameters, including air quality, noise, traffic data, and social impact of the measures.
The reduction of polluting emissions was pursued by means of the following strategies:
1. Traffic flow management during heavy traffic situations by combining dynamic speed limit reduction and dynamic lane activation strategies.
2. Dynamic management of the maximum speed limits allowed according to air quality.
3. Traffic flow management near the biggest urban areas by means of “intelligent” onroad information.
A complex, intelligent traffic system (ITS) was created to let the traffic management centre (TMC) of the A22 dynamically activate the variable speed limits (VSLs). The forecasting mechanism utilizes data integration facilitated by the Open Data Hub, to gather all pertinent sensor measurements. Using a ‘traffic state machine’, the system ascertains real-time traffic conditions and proposes various variable speed limit (VSL) options based on congestion levels. To mitigate high NO2 levels, the system evaluates several factors, such as traffic-related emissions data, weather forecasts, atmospheric stability, and estimates of nitrogen oxide concentrations, to determine the appropriate VSL measures.
The infographic showcases the methods for managing highway traffic. With measurement systems installed alongside the highway, the A22 traffic management centre (Centro Assistenza Utenti CAU) can receive real-time updates about specific traffic incidents, such as heavy traffic causing congestion, and detect critical air quality situations, like surpassing reference NO2 concentration thresholds. Consequently, the centre can take prompt action by implementing new dynamic and pre-coded measures under the control room operators’ supervision. In particular, dynamic speed limits can be applied on different road stretches to reduce traffic-generated emissions and enhance the stability of traffic flow. Additionally, the system can operate proactively to anticipate certain events and activate the measures in advance, thereby increasing the effectiveness of the implemented measures.
The infographic depicts a future scenario of integrated traffic management between the highway and cities, which is one of the project’s objectives. In the event of a traffic incident within the urban area, such as an accident, the urban traffic management centre informs the A22 traffic management centre (Centro Assistenza Utenti CAU). The Open Data Hub facilitates the technological exchange of information by creating interfaces with local-level systems and disseminating relevant information to all concerned parties. Following established procedures (and assuming no other concurrent events on the highway), the highway operator can mitigate the negative externalities of the incident by activating appropriate messages on variable message signs (and all other traveller information services), such as advising drivers leaving the highway and entering the city to use an alternative route to reach their intended destination.
The most innovative aspect of the project is the development of a forecasting model of weather, environmental and traffic conditions that will form the basis of a proactive decision support system for the optimal management of vehicle flows and the reduction of environmental impacts in a particularly sensitive area such as the Alpine valleys.