Controlling pollution through real time traffic management
With increased traffic pollution plaguing Europes cities, a near real-time vehicle pollution monitoring system that correlates traffic conditions and the resulting levels of pollution has been developed and road-tested and should help to create healthier urban environments.
Maurizio Tomassini, coordinator of the HEAVEN project, describes it as "a system for connecting real-time traffic data to emissions and concentrations due to vehicle pollutants. End products are near-real-time maps showing the distribution of CO, NOx, benzene, particulates and noise pollution. The system has been trialled in six European cities: Berlin, Paris, Rome, Leicester [UK], Rotterdam and Prague."
"There was a definite need for HEAVEN," adds Tomassini. "Each city has its own way of doing things. One department looks after communications, another after traffic management, another environmental matters, and so on. There was no single integrated platform that could integrate and diffuse the information to the city departments together and to citizens. The HEAVEN architecture has been developed according to a general framework, but with the capability of easily incorporating specific solutions and requirements."
In addition to providing near-real time information, databases are being built up for subsequent modelling. One could have a scenario, for example, that took into account traffic flows and weather conditions to know the overall environmental impact. The scenario, via the traffic demand management strategy (TDMS) simulation feature of the Heaven system, can be played through, hour by hour, to see what the net benefits might be. Parameters, such as average traffic speed as a function of the time of day, can be adjusted.
TDMS for real: the examples of Berlin and Leicester
With funding from the IST programme, HEAVEN was used to study TDMS and pollution levels in Berlins Beusselstrasse, a street that has a substantial flow of heavy goods vehicles. Two TDMSs were evaluated: one with the imposition of a 30 km/hr speed limit; the other a total lorry ban. The results will have a strong influence on future traffic planning because the study indicated that, in the long term, it may be difficult to comply with future environmental limits, particularly those for NO2 and PM10 (particulate matter).
Subsequent analysis showed that the Beusselstrasse TDMSs was only partially successful. The average speed was reduced to only 38 km/hr (instead of 30), and 50 per cent of goods lorries ignored the ban. Nevertheless, HEAVEN showed that there was a noise reduction of 1-2 dB(A), NO2 was reduced by 10 per cent and particulates by 8 per cent. These results are consistent with those predicted by models developed within HEAVEN.
In Leicester, HEAVEN was used to support local council decisions that span several administrative boundaries. Assessments have been conducted for the Local Transport Plan and the Air Quality Review, and the advantages of several TDMS were quantified.
One of the key findings is that it is impractical to consider reducing vehicle speeds in Leicester by 20 per cent because it will cause peak traffic flows to spread out. Another finding is that restrictions on access for heavy goods vehicles and the promotion of park-and-ride schemes will have a positive benefit for noise levels and air quality on account of the significant reduction in traffic flow.
Decision support and legacy systems
"HEAVEN is particularly effective because the construction of traffic flow data comes from the extrapolation of real situations," adds Tomassini. "Its not a pure assignment model that might be found with conventional planning models." HEAVEN supports the decision-making process by integrating traffic and environment legacy systems, which enables real-time air quality, traffic and information management, and facilitates the assessment of the environmental impact of different TDMSs.
The HEAVEN toolkit includes: a comprehensive decision support framework that enables data to be transferred to other application sites in line with local characteristics and requirements; a reference architecture with open interfaces that facilitates the integration of existing systems and models, and a range of validated applications covering environmental modeling, model integration and operational schemes. There is also a set of validated short- and long-term traffic scenarios to counter the adverse effects of pollution on the environment, and a set of practical case studies on the environmental benefits of implementing traffic measures.
"In Rome, where I work," says Tomassini, "the system is being used as an operational prototype. The city has decided to engineer the system so that it becomes part of the official operational support system."
Società Trasporti Automobilistici
Via Ostiense 131/L
Source: Based on information from HEAVEN
Tara Morris | IST Results