Ask for a better distribution of traffic
You tackle the following challenges:
That's how you do it
With a redistribution of traffic, one opts for a dynamic or static redistribution of traffic by introducing alternative routes or parking options, or by allowing traffic in a certain zone only at certain times. The aim is to reduce both congestion and air pollution.
While there is sufficient evidence that infrastructure changes can effectively redistribute traffic, little data exists on the effects on air quality. Moreover, the few available studies deal with specific situations and should not be generalized.
As a rule of thumb you can say that redistribution of traffic only affects local pollution, and only when the measure is in effect. The effects will therefore be greater for nitrogen dioxide and soot than for particulate matter.
- Particulate matter (PM) : unknown
- Nitrogen dioxide (NO 2 ) : unknown
- Soot (EC) : unknown
- Other pollutants : unknown
Redistributing traffic also offers the following additional benefits:
- A zone with less traffic is more attractive as a residential area, especially if you encourage outdoor activities and increase the sense of well-being
- The zone becomes more prosperous
- Less traffic leads to fewer traffic accidents
Knowing more
Traffic redistribution through new infrastructure
Oslo, Norway - 1987-1996
A study with dispersion models (calibrated with control stations) evaluated the health consequences of a new tunnel infrastructure. The hourly concentration of NO 2 near homes decreased from more than 50 to about 40 µg/m³. The study showed measurable health benefits when choosing to redistribute traffic to reduce pollution.
Traffic redistribution through new infrastructure
Amsterdam, The Netherlands
Restructuring of a highway corridor (Schiphol-Amsterdam-Almere) to reduce traffic congestion and improve mobility. As part of a feasibility study, the Dutch government also studied the effects on air quality and health. The conclusion was that the measure produces a small improvement in the NO 2 content (2% reduction) and the health of the population (less than 5%).
Traffic redistribution at certain times
Oakland, California, USA - 2008-2009
Shifting activities to nighttime offers many advantages, although one has to take into account possible unintended consequences due to the weather conditions. At night and early in the morning the air usually moves less, so that the air is less diluted. However, environmental benefits are also expected, for example due to a less busy morning rush hour.
Redistribution program with a coordinated traffic management control system
Dunstable, UK - 1999-2004
By linking traffic lights to a regular traffic management system, the aim was to optimize traffic flow through Dunstable and reduce congestion. However, the smoother traffic flow led to more traffic so that the air quality in Dunstable did not improve.
Park & Ride Facilities
Amsterdam, The Netherlands
By setting up car parks on the outskirts of the city and near highways, and combining this with excellent connections with public transport, the aim is to convince people to drive into the city by public transport.
More information
- The National Audit Office Memorandum (2006) provides an analysis of an implemented traffic redistribution program. The report gives good tips for ways to test whether the goal has been achieved.
- A good example of a successful program is given by Schram-Bijkerk, et al. (2012) .
