ACCESSIBILITY IN THE URBAN ENVIRONMENT FOR CITIZENS WITH IMPAIRMENTS: USING GIS TO MAP AND MEASURE ACCESSIBILITY IN SWEDISH CITIES

摘要

Since the design of our cities tends to constrain people with impairments from perform-ing their daily activities, removing barriers and making public space accessible for eve-ryone is becoming a human rights-issue. Due to an ageing population, the number of impaired citizens is expected to increase substantially over the next 50 years. Hence, there is a current demand on urban planners to find a way to adjust their cities, in order to make them usable for everyone, which will grow stronger as the number of elderly in the society increases over the next few decades. However, to efficiently improve acces-sibility requires knowledge about the location of obstacles in the urban environment and how these affect accessibility. Using GIS-models to map and measure accessibility, this study aims at providing new knowledge about the spatial distribution of accessibility and the possibility for impaired persons to travel independently in eight Swedish cities. Furthermore, the study aims at revealing differences in accessibility between different types of neighbourhoods. The study will thus provide new knowledge on how accessibility is affected by the heritage from the different planning principles and guidelines that have influenced the develop-ment of the urban environment over the past century. Based on field inventories, detailed digital models of the pedestrian and public transport networks were created for each city, using traditional digitizing methods. Using GIS for network analyses, accessibility was measured by calculating travelling times and dis-tances between home and different destinations, such as grocery stores, bus stops, health care centres, pharmacies or the train station. The method pays attention to the entire travel chain, thus analysing the possibility to reach a destination using a combination of available and usable modes of transport between home and destination. The results from the study reveal how different types of flaws in the pedestrian network cause interruptions or forces travellers to detours, which restricts accessibility. The results show where it is possible to live and independently perform daily activities as an impaired citizen and also how travelling times and distances vary considerably between impaired and non-impaired citizens. For the mobility impaired, their sensitivity towards long distances and steep slopes turns out to be more restricting to accessibility than specific details in the physical environment. Accessibility for the vision impaired is restricted mainly due to the insecurity and discomfort caused by a lack of physical separation between pedestrians and bicyclists on a large proportion of the pathways, but also due to problems related to crossing the streets. The results also reveal significant variations between the different types of neighbourhoods within the study area, but also between the different cities included in the study. Residential areas designed according to the principle of complete segregation of pedestrians and motorized vehicles provide the most favourable environment for those with mobility impairments, whereas the town centres provides the least problematic environment for the vision impaired. In conclusion, the study shows how urban planners, by using GIS-models, can easily enhance their knowledge about how flaws in their cities affect accessibility for impaired citizens. Furthermore, the study shows how planners could easily use these models to simulate potential actions towards improving accessibility. The results from such simu-lations reveal what effect a certain action would have on accessibility for impaired citi-zens, thus making it possible to identify and prioritize those actions that would generate the most positive outcome.