Since the 10^th of January 2014, the speed limit in the Parisian Périphérique went from 80 to 70km/h. This measure was to bring a number of benefits and aspects, whether from the point of view of road safety or that of the environment. In fact, this axe on the 35km of length represents 40% of the Parisian traffic which is a considerable factor to the pollution in the capital, since it has been responsible for 37% if the nitrogen oxide emissions of road traffic in Paris. ADEME looked into this subject and concluded that a reduction of 10km/h to the speed limit of the Périphérique Boulevard would allow carbon emissions to drop by 5%. What’s more, 4 million tonnes of CO² emission per year could be avoided, as well as saving drivers 10 to 15% off their fuel from €100 to 200 per year. Yet, to this day it’s still too early to tell the effectiveness of this measure under this angle, other figures have been very promising. At the end of six months, traffic jams have been reduced by 37% over an average duration of 104 minutes per day to just 66. The flow of traffic is a sign that will be able to indicate whether the pollution can be effectively found to be diminished. However, if sound pollution is known to drop 1.2 décibels at night and 0.5 in the day, this difference is too small to be noticed by ear by the 100,000 inhabitants living by the Périphérique. For something more efficient, it could be that the future speed limit could be restricted to 50km/h at night on this major road.

From the tunnel of the Porte d’Auteuil on the Boulevard Périphérique in Paris, France, to the south side of the tunnel, in the 16th arrondissement of Paris.
Photo credit: Geralix

All the information on the Parisian Périphérique (in French).

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