Making reachability visible with data

Whether it's work, a visit to the hospital or a meeting in the pub, the journey is often a means to an end. How this journey takes shape is determined by personal preferences, but also by one's own prerequisites, such as possession of a driver's license.

A decisive factor in the choice of means of transport is the infrastructure. It influences how quickly and by what means destinations can be reached. The indicator of accessibility can be used to evaluate infrastructure in terms of transportation planning, especially against the background of individual prerequisites. It expresses how well developed an area is: Where are supermarkets within walking distance? Where is a car needed? "The accessibility approach is a great way to see where improvements can be made," summarizes Ulrike Jehle, co-managing director of Plan4Better.

With her team, Jehle is developing a tool to answer such questions: the Geo Open Accessibility Tool, or GOAT for short. The web portal bundles mobility-relevant geodata from several sources and provides simple analysis tools: Heatmaps, isochrones and indicator evaluations make it clear which areas in a city are served how well for different needs in each case.

The first prototype was developed in a master's thesis by Elias Pajares. When he subsequently worked at TUM, the idea received funding from the mFUND initiative of the German Federal Ministry of Transport. This allowed him, Majk Shkurti and Ulrike Jehle to work full-time on further development, as Jehle reports. "Towards the end of the project, we got such good feedback from our project partners, the cities of Fürstenfeldbruck, Freising and Munich, that we decided to found a start-up. This way, we can now bring what we developed in research into planning practice." Pajares and Jehle now form the management team of Plan4Better GmbH, which now employs eleven people. In a consortium that again includes TUM and the Leibniz Institute for Ecological and Regional Development, GOAT 2021 received follow-up funding to take the tool to the next stage of development.

GOAT is intended primarily as an aid for municipalities and planning offices: "A major goal with GOAT is to make accessibility analyses accessible, even without a degree in GIS (geographic information systems, editor's note)." To do this, the tool combines data from a variety of sources: OpenStreetMap, population statistics, timetable data and other sources are used to compile an overall picture. The more that is available, the better. The tool itself is being developed as open source from the start, so it is available to anyone who wants to install their own version. Development is focused on Germany, but the principle is transferable: According to Jehle, it was possible to offer a version for the Belgian city of Ghent relatively quickly, which is "in no way inferior" to the version for Munich - thanks to good public geodata.

But GOAT can be used not only to examine the status quo, but also scenarios for possible changes: What effect will a pedestrian bridge have? How well is a new residential area served? Anyone who wants to can try out the effect in scenarios, but also upload their own point data sets and include them in the evaluation. In addition to various graphical representations such as heatmaps and isochrones, many of the results can also be exported again. For the hexagonal heatmaps, however, they are still working on it: GOAT is functional, but there are always new ideas. Improvements are to be made, for example, in the mapping of intermodal travel chains or the integration of open space planning. In addition, the focus is on the 15-minute city, in which all important destinations are never more than a fifteen-minute walk (or bike ride) away: The goal of Plan4Better is to be able to show in an aggregated index value how well this principle is already realized in a city and in which category there are strengths and weaknesses.

Others are also interested in making the 15-minute city more tangible. On the website 15-Minuten-Stadt.de, for example, two committed Giessen residents have evaluated data from OpenStreetMap: They show where particularly diverse facilities from the areas of mobility, local supply, leisure, health, education and local recreation can be found and rate this on an aggregated scale. The Map4Citizens tool, also from Plan4Better, queries personal needs and thus shows individual accessibility using the example of the city of Munich. Research at the TU Berlin on mobility planning and on a mobility index shows that individual and social needs in particular have an influence on mobility and thus also on accessibility.
With better models and a more differentiated understanding of mobility, accessibility is changing from a vague feeling to a quantifiable value.