Visioning versus Modeling: Analyzing the Land-Use-Transportation Futures of Urban Regions

摘要

In recent years, the use of visioning processes and scenario-planning tools for developing regional land-use scenarios has become rather common. Typically, visioning is performed as a cooperative, inclusive process among business owners, community residents, interest groups, and local officials, and results in broad goals and principles which can guide future policies and plans. This is a very different approach than a land-use modeling process, which is typically generated by technical experts and results in a set of probable future trends and indicators which can guide the implementation of growth management strategies. The scenario-planning tools typically used for visioning processes are designed to generate and compare potential and preferred future development scenarios based on stakeholder values and preferences, whereas land-use models are used to predict likely future development patterns based on mathematical equations, reflecting historical trends, and market forces. Consequently, direct comparisons of results for the two methods are not really relevant. However, it is important to understand how the two approaches differ and that both offer their own relative advantages from a planning perspective. In an effort to better appreciate what each approach offers, this paper compares and contrasts these two methods, featuring the Austin metropolitan statistical area as a case study. The preferred vision, produced by the Envision Central Texas organization, offers the greatest potential for public involvement in identifying regional development goals for the future. The land-use models have a strong theoretical foundation and allow for interactions with a transportation model. Moreover, the land-use models have the potential to identify key strategies that can be used in achieving the region's goals. Thus, the combination of these two approaches seems to offer the greatest opportunities for planners to achieve a future that accommodates all stakeholders.