Yhdyskuntarakenne ja liikenne vuorovaikutuksessa : esimerkkinä joukkoliikenteen saavutettavuus Kouvolan seudulla

Public transport services can guarantee the travel opportunities for citizens without a car. Also congestion and the emissions of traffic can be reduced by developing the public transport services in urban regions. However, increasing the mode share of public transport is not simple, because the travel behaviour of citizens is influenced by the transport system, the norms of society and urban structure. The aim of this study was to find out what kind of effects urban structure has on the travel options and choices of the citizens. The case study of the Kouvola region attempted to look into the relationship between urban structure and the opportunities of using public transport i.e. the accessibility of public transport. The public transport accessibility on the study area was analyzed using the geographic information system (GIS) and statistics. The literature review shows that, amongst other things, population density, the type of the residential area and the distance from the city centre are all factors connected to the citizens' travel behaviour. The houses in the study area are mostly one-family houses and therefore the population centres are relatively sparsely populated. That makes it more difficult to organize public transport in an economical way. On the other hand, a significant proportion of the population lives near centres, which usually reduces the need of private cars. Also the high accessibility of public transport can reduce driving by private car. This idea is supported by the finding that in the study area, there are less households with more than one car and more households without a car in the areas with good public transport accessibility than in other areas. Owning many cars becomes more common and living without a car less common when the accessibility of public transport declines. In the population centres of the study area, the accessibility is on a good level. In the countryside, there is no public transport that can compete with private cars, but in many villages, the accessibility is on a reasonable level. The relationship between urban structure and citizens' transport choices is complex, and the relationship between these phenomena is not necessarily causal. However, the possibilities offered by urban structure are a prerequisite for the people to be able to make the choices they want. In dense urban structure, it is more economical to provide public transport services and easier to walk or cycle than in dispersed structure. One of the future challenges in the study area is to build new houses in areas where it is possible to provide the residents with diverse travel options. The chances of infill development are limited in an area with decreasing population. The consolidation of municipalities in the Kouvola region in 2009 still affects the service network of the region, which in part influences the citizens' travel needs together with the ageing of the population. In order to reduce the car ownership of households, it is important to develop the transport system so that the different transport modes complete each other.