Rising speed limits raise environment, air quality concerns

The increase in speed limits to 130 kilometers per hour taking effect on many highways today, will compromise the air quality, according to researchers from both the RIVM and TNO. These researchers believe it likely that the increased speed limits will result in the Netherlands exceeding the European standard for air quality, the Volkskrant reports.

These expectations stand in stark contrast to what Minister Melanie Schultz van Haegen believes. She commissioned engineering firm Tauw to study what impact increasing the speed limits would have on air quality and the environment. That study concluded that there will only be a limited increase in the amount of nitrogen dioxide, mainly released from diesel car exhaust fumes, in the air. According to the Tauw figures, the annual average for nitrogen dioxide concentration is 38  micrograms per cubic meter of air. The European standard is 40 micrograms. The margin of 2 micrograms is sufficient to make sure the standard is not exceeded, according to the engineering firm.

State research institute RIVM is much less positive. Working with the same models as Tauw, among others, the RIVM thinks that outliers of 8 micrograms above or below the limit are possible. This wide range is due to uncertainties in the data the RIVM worked with. This means that the actual nitrogen dioxide concentration can actually be much higher than the calculated 38 micrograms, according to the newspaper.

In addition to uncertainties in the calculations, NO is also concerned about indications that the nitrogen dioxide emissions from new diesel cars are higher than assumed and about an increase in traffic. "A unexpectedly sharp increase in traffic was recently observed, presumably due to the economic growth", researcher Norbert Ligterink said to the newspaper. Additional traffic can also lead to higher emissions, not included in the calculations.

Environmental organization Milieudefensie (the Netherlands' Friends of the Earth) thinks the speed limit increase is indefensible. "A smokescreen of false security is being raised, making it seem that there is no risk of the standards being exceeded if the speed is increased", traffic campaign manager Anne Krol said to the Volkskrant. "It is impossible to calculate on every street corner exactly how polluted the air is and how it will be in the future. Everyone understands that, but the Ministry refuses to see the consequences."

Minister Schultz acknowledged that the air pollution will increase slightly, but insists that it will stay within the legal requirements, a spokesperson said to the newspaper. She also announced that it will be checked annually. Measurements along routes where the speed limit was already 130 km/h showed that the nitrogen dioxide concentration never exceeds 35 micrograms.