IEHIAS scenarios: example from transport
- The text on this page is taken from an equivalent page of the IEHIAS-project.
As part of the EU-funded INTARESE project, which contributed to the development of this Toolbox, a series of case studies were carried out to assess health impacts associated with road transport in several European cities. One of these, in Helsinki, focused on congestion charging.
Congestion charging (CC) has been proposed in Helsinki as a means to mitigate traffic congestion and health impairment due to increasing traffic volumes.
The region of interest in this assessment consisted of four municipalities in the Finnish capital region: i.e. Helsinki, Espoo, Vantaa, and Kauniainen, which until 2009 constituted the administrative entity of the Helsinki Metropolitan Area (HMA), with a total population of ~1 million and an area of ~740 km2. The assessment was designed to compare health impacts under a hypothetical policy of congestion charging (CC) to a business-as-usual (BAU) scenario.
Sources and their impacts under both years were modelled for the base year of 2005. For the CC policy, a three-zone charging scheme was assumed, in which personal cars must pay a fee for public road use during weekdays. The fee was assumed to be distance-based and dependent on the zone and time of day. Thereby, the technical implementation of CC was taken to rely on global positioning system (GPS) and vehicle telematics. Within the CC policy, 3 sub-scenarios were examined, differing in the levels of fees - i.e. "high fees", "low fees", and "one-zone fees" (see Table 1, below). Public traffic flows were assumed to remain unchanged (in terms of vehicles/h), on the assumption that increased demand could be met by an increase in capacity (e.g. bus size) and/or utilization rate. The numbers of trips by public transport (and light transport) were obviously allowed to change.
| Innermost zone | Middle zone | Outermost zone | |
|---|---|---|---|
| Business as usual | 0 | 0 | 0 |
| Low fees | 20 | 13.3 | 6.7 |
| High fees | 40 | 26.7 | 13.3 |
| One zone fee | 40 | 0 |
The scenarios were defined in close collobaration with the municipality of Helsinki, a key stakeholder. Specifically officials from the Tranport Department contributed to discussions about which scenarios were ambitous yet realistic in terms of selected prices, hours and geographical coverage. Exisiting congestion charge schemes in London and Stockholm were also examined, to inform the choice of scenarios. Extensive use was made of Wiki-pages to invite comments on the scenarios in a transparent way.
Though the scenario was developped specifically for this case study, the city council of Helsinki has since launched an evaluation of the feasibility of CC to mitigate traffic-related problems in the capital region, an option that is also favoured by most inhabitants of the area. Therefore, this assessment provides highly policy-relevant information of general interest, for decision-makers and inhabitants alike.