Is there a significant quantitative connection between elements of the urban planning in the two medium-sized towns of Groningen and Maastricht and bicycle use in the modal split of both towns? Why does bicycle use vary so much in Groningen and Maastricht, considering the urban planning on the one hand and the effect of urban planning on bicycle use in these towns, on the other?
The municipality of Groningen is interesting because of the very high percentage of all bicycle journeys in the total number of journeys. Of the 40 largest municipalities, Groningen is the town with the second highest figures for bicycle use. After an original analysis based on 6 variables (bicycle detour factor, the difference between the bicycle detour factor and car detour factor, the population density per km2, actual distance of the journeys in meters and the travel-time relationship bicycle/car), some of these variables proved significant with respect to changes in bicycle use. It can be concluded that population density and the detour factor for bicycle journeys explain the majority of the changes in bicycle use and that the urban planning characteristics together cause at least 80% of the impact on differences in bicycle use.
The great difference between Maastricht and Groningen is the share of bicycles in the modal split. With 44%, Groningen has the second number of bicycle journeys in all journeys travelled, while in Maastricht only 25% of all journeys are made by bicycle. In order to analyse the effect of various urban characteristics on bicycle use, initially seven variables were chosen (the same as Groningen and 'age'). Due to sufficient reliability, six of these are part of the regression comparison. The factors which have the greatest impact on differences in bicycle use in Maastricht are the cycling distance and the age of those making the journey. In total, the urban planning elements in Maastricht only explain a small part of bicycle use. The logistic-regression model produces a correct forecast of bicycle use in 15% of the cases. This shows that in Maastricht other factors than urban planning are more important (for example socio-cultural background).
When the present policy is studied, it can be concluded that in Groningen and Maastricht the choices are focused on those attention points which can achieve the best results for both towns. Groningen mainly focuses on making cycling more attractive by investing in the cycle path network (pull-measures). This seems justified given the great effect that changes in urban planning can have on bicycle use. In Maastricht, attention is mainly focused on behaviour change and a selective approach to bottlenecks. This seems to correspond with the great impact of planning-dependent factors.
With regard to the difference in bicycle use between Groningen and Maastricht, the following can be concluded. It has already been said that there is only a slight effect of differences in urban planning on the variation in the use of the bicycle in Maastricht. This implies that the effect of other factors (for example socio-cultural background) is relatively great. The absolute difference in bicycle use will have to be sought there. With regard to urban planning, it can be concluded that bicycle traffic in Maastricht, also due to the division of the town by the River Maas, will have more disadvantages from barriers. The detour factor is higher in Maastricht than in Groningen. Furthermore, in Maastricht the car needs to make relatively fewer detours than the bicycle.