This paper presents an IT infrastructure based on an event driven architecture with the objective to decrease the turnaround time for urban planning. Most urban planning takes a long time, not only to get all stakeholders involved, but also to assess various scenarios on several aspects according to (inter)national laws and regulations. By supporting urban planning with IT, the turnaround time is expected to decrease dramatically and supports the possibility to explore more scenarios without an extra burden on duration and personnel. The IT infrastructure developed integrates various data resources and calculation models for analyzing different scenarios. An event service bus and a data store for sharing data between computational models is the basis of the infrastructure. Various computational models are able to read and write to the data store and publish and subscribe to events. Based on a case study, the paper illustrates that indeed decision making is improved leading to better and possibly cheaper urban plans for all relevant stakeholders. The paper will also show that a closed environment, as currently available, is one of the major thresholds for acceptance by end-users. End-users would like to apply their computational models, which can not yet be plugged into the infrastructure. Further extensions are foreseen in applying open standards and open link data for data collection and sharing. Thus, interoperability is a prerequisite for our IT infrastructure.
Keywords: Interoperability, Infrastructure, Flexibility, Event driven architecture, Urban planning
Cities can be viewed as dynamic socio-technical systems that interact with a continuously changing world . Therein, the technical network and the actors and bodies of rules that are involved - the social network - together form an interconnected complex network (Figure 1). In the technical network material, energy, money and information are transformed and exchanged over suitable interfaces. The social network considers all stakeholders and their (in)formal relationships, e.g. contractors, architects, project developers, building societies and of course municipalities. These stakeholders all have vested interests in a city, e.g. because they own property or intend to exploit new property. Developments are ruled by various national and international regulations, e.g. EU regulations contain agreements regarding pollution that are guiding changes in cities and infrastructures. Cultural differences define how stakeholders participate in developments.
Much like natural ecosystems, our cities can be seen to constantly evolve because individuals, organizations and governments decide on, for example, development, restructuring, demolition, transport infrastructure, energy grids, sustainable housing, shopping, (dis)investment, coordination & regulation, respectively, in response to and in interaction with their respective environments. With time, cities evolve and complex structures emerge, which are characterized by diversity, multiple interactions both within and between layers, feedback loops and emergence - all characteristics that lead us to consider them as "complex". In such a complex system, control is distributed over the various actors - there is no single actor determining the configuration and behaviour of the system. With time, a system structure assembles and total system behaviour emerges .
Planning for cities today has additional environmental and social priorities in common with many topics that concern industrial ecology . It implies for instance that urban development projects require an Environmental Impact Assessment (EIA, ) and Strategic Environmental Assessment (SEA, ) according to EU directives  and the United Nations/Economic Commission for Europe . Environmental aspects that need to be included are direct and indirect effects of plans on (1) human beings, flora and fauna, (2) soil, water, air, climate and the landscape, (3) the interaction between the factors mentioned in the first and second indent, and (4) material assets and the cultural heritage. …