Integrated Land Use, Transportation and Environmental Simulation: UrbanSim

The process of planning and constructing a new light rail system or freeway, setting an urban growth boundary, changing tax policy, or modifying zoning and land use plans is often politically charged. Our goal in the UrbanSim project is to provide tools for planners and stakeholders to be able to consider different scenarios — packages of possible policies and investments — and then, based on these alternatives, model the resulting patterns of urban growth and redevelopment, of transportation usage, and of resource consumption and other environmental impacts, over periods of twenty or more years. UrbanSim [1, 3, 4] performs simulations of urban development, including transportation, land use, environmental impacts, and their interactions. It consists of a set of interacting component models that simulate different actors or processes within the urban environment. The system is written in Java, and is distributed as Open Source software. (Source code, as well as papers and reports, are available from www.urbansim.org.)