Large real estate developments, spatial uncertainty and integrated land use and transportation modeling

In the past 10 years, integrated land use and transportation modeling has received considerable attention in the scholarly literature. This academic interest is slowly yielding practical applications. In the USA, many metropolitan planning organizations (MPOs) and state departments of transportation are beginning to implement these types of model for the first time. While many improvements have been made to these models, and the value of these improvements should not be understated, much work stilt remains. One of the most challenging problems in land use modeling is how floorspace (buildings) is built and occupied. The purpose of this article is twofold: first, to draw attention to insufficiencies in the representation of floorspace developer behavior-particularly as it applies to large, urban-edge projects - within current integrated land use and transportation models and, second, to determine the necessity of explicitly accounting for such projects within these models. The Sacramento MEPLAN model will be used together with historical development records to demonstrate and test these assertions. Single large developments are modeled with a common year of development, size, and location. Among the findings, large developments are fairly common in the Sacramento region and make up a considerable amount of floorspace development in absolute terms, large basic sector developments have more of an impact and are therefore more important to explicitly account for than are large non-basic sector developments. A single large basic sector development modeled in a 20-year forecast has a significant impact on zonal outputs. Recommendations are put forward regarding the use of this research in practical modeling exercises.