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Accessibility indicator: access by car in 2012

The general picture is that car accessibility (the door-to-door as-the-crow-flies travel speed), in 2012 in the morning rush hour barely differs from the evening rush hour. Car accessibility of the Randstad region puts in a negative way against the rest of the Netherlands. It is also striking that, car accessibility in the South Wing of the Randstad region is less good than in the North Wing Randstad region, especially during the morning rush hours.

Car accessibility during morning rush hours better than during the evening rush hours

Car accessibility is defined as the door-to-door as-the-crow-flies travel speed for passenger traffic for areas in 2012 for both the morning (7-9 am) and evening rush hours (16-18 hours).
The color of an area in the map indicates the accessibility of an area from all other areas in the Netherlands, while the size of the circle shows the total number of trips to this area. If an area has a 'red' color, it means that the accessibility of this area is worse than average in the Netherlands.
The general picture is that the accessibility by car in the morning rush hours in almost all areas hardly differs from the evening rush hours and car accessibility of the Randstad region negatively stands out against the rest of the Netherlands. It is also striking that, in the South Wing of the Randstad region, the accessibility by car in the morning rush hours is less than in the North Wing of the Randstad region.

Composition accessibility indicator

The accessibility indicator described in the National Policy Strategy for Infrastructure and Spatial Planning (SVIR) focuses on the door-to-door as-the-crow-flies travel speed for journeys made to certain areas. In this baseline the accessibility indicator is determined based on measured speeds. These rates are derived from navigation systems and are an average for all road users (passenger car and freight). The data quality for the national and provincial road network is better than for the other roads. From 2014 there will also be more reliable driving speed data available for the remaining road network.
Travel times between areas are derived from driving speed data. In order to determine the accessibility indicator also the number of trips between areas are necessary in addition to travel times. This requires the origin-destination data of the trips in the base year of 2010 the national model system (LMS) used.
The average door-to-door as-the-crow-flies travel speed of the accessibility indicator is calculated for the trip distance to a destination. And can give a picture of the current regional differences in the door-to-door as-the-crow-flies travel speed. The accessibility index is calculated for every area by dividing the door-to-door as the crow flies travel speed to that area on a reference value. The index indicates whether the door-to-door as-the-crow-flies travel speed to an area is higher or lower than the reference value. A speed higher than the reference value thus leads to an index less than 100, and a speed less than the reference value to an index above 100.
The relationship between the trip distance to an area and the average speed to that area, derived from the used data, defines for each trip distance a reference value. This method takes into account the fact that in areas with a high degree of urbanization close proximity to amenities is relatively large and the distances traveled, and therefore the average speed, is relatively low. For example, areas for which the average distance of trips is higher, also have a higher reference value, than areas of relatively short trips.

Restrictions accessibility indicator

This baseline assessment focuses mainly on accessibility by car. Limited data availability made it impossible for the baseline even for public transport and cycling to provide insight into the accessibility based on measured speeds.
The as-the-crow-flies travel speeds differ greatly between transport modes and on the distance travelled. The direct travel speed is lower for short distances than for longer distances, due to the higher detour factor (people travel less in a straight line over shorter distances) and the lower proportion of travel on the motorway. This means that not just the quality of the network affects the travel speed, but also the distribution of the trip distances (many or few short trips). An indexed accessibility indicator is therefore used to correct for this.

References

Archive for this indicator

Reference for this page

CBS, PBL, RIVM, WUR (2016). Accessibility indicator: access by car in 2012 (indicator 2138, version 02 , 5 February 2016 ). www.environmentaldata.nl. Statistics Netherlands (CBS), The Hague; PBL Netherlands Environmental Assessment Agency, The Hague; RIVM National Institute for Public Health and the Environment, Bilthoven; and Wageningen University and Research, Wageningen.

The Environmental Data Compendium is a partnership of CBS, PBL, RIVM and WUR.