Does Planning Matter?
Land use planning involves intertemporal decisionmaking—the consideration of a subsequent decision before a first decision is made. Decisions in the urban development process include the purchase, assembly or subdivision of land; the provision of transportation, electric, water and wastewater services; the application for and approval of building permits; and the sale of improved property to final users.
The ability to analyze this process has been limited by the lack of dynamic models of development stages, time-series data on land use decisionmaking, and empirical approaches to analyzing multiple events in time and space. In part for these reasons, there has been almost no empirical evidence on the process of planning or the effects of plans on subsequent development.
To gain new insights into the effects of planning on the urban development process, we have developed theoretical models of urban planning, constructed a dynamic geographic information system, and developed computer algorithms for interpreting and displaying urban development events. The information system is characterized by a high degree of spatial and temporal resolution and the ability to observe development activity over time.
As a result, the information system facilitates the observation of spatial and dynamic processes that characterize urban development, the formation and testing of hypotheses about such processes, and the exercise of high-resolution simulations based on statistically confirmed relationships.
Study Site on Portland’s Westside Corridor
The information system is built upon the Regional Land Information System (RLIS) developed by Metro, the regional government of Portland, Oregon. RLIS is a comprehensive Geographic Information System (GIS) containing layers that depict tax lots and their attributes; planning designations and zoning regulations; soil, water and environmental resources; infrastructure facilities and capacities; government boundaries, tax districts and transportation zones; and census data for the entire Portland metropolitan area.
RLIS has been enhanced to include attributes of development events, such as land sales, subdivisions, and changes in plan designations and zoning. Although the system currently includes only the years 1991 to 1995, it is an unusually comprehensive, high-resolution, and dynamic research and planning tool.
To test the utility of the information system, we examined the urban development process in Portland’s Westside corridor, where a new light rail system is scheduled to begin service in 1998. Construction of the Westside segment began in 1992, and the far western station locations were finalized on July 28, 1993. When complete, the Westside line will connect the western suburbs of Hillsboro and Beaverton to downtown Portland and to the eastern sections of the light rail system.
Ambitious plans for the metropolitan area call for high-density development along Portland’s light rail corridors to contain growth within the urban growth boundary. By focusing on the Westside corridor, it is possible to evaluate whether the development decisions and transactions of land owners and local governments are influenced by anticipated light rail infrastructure investments and consistent with regional development plans.
Mapping the Development Process
The development process can be examined using dynamic geographic visualization—that is, the observation of urban development events at varying temporal and geographic scales. Using a tax-lot base map, for example, and by illuminating tax lots when certain events occur in a sequence of frames, it is possible to watch the urban development process much like a movie. The sequence of frames printed in this issue of Land Lines illustrates selected development activities from 1991 to 1995 in an approximately one-square-mile area around the proposed Orenco light rail station. Since it is difficult to reproduce the frames here, please go directly to the authors’ web page for mapping details at http://www.urban.uiuc.edu/projects/portland/lincoln.html
The first frame shows the sale of several large industrial properties in 1991, when the route of the rail line was known, but not the station location. In 1992, a demolition and construction permit was issued on a large industrial parcel. The third frame shows the station location, with development on industrial land near the station and increasing sales activity in the subdivision in the northwest corner of the study area.
The fourth frame shows that a station overlay zone was adopted in 1994. It subjected building permits in the station area to a special review process to assure that proposed developments are transit supportive. The frame also shows a marked increase in residential sales in the northwest subdivision and in the old town of Orenco in the inner southeast corner of the study area. The fifth frame shows a continuation of sales and development activity in both residential and industrial parts of the study area.
This series of frames captures an intriguing pattern of development events. First, the number of sales and permits in the study area before the announcement of the station location suggests that the station was sited in an area of active industrial development. Second, the activity in both the conventional subdivision in the northwest corner and in the township of Orenco indicates that the announcement of the station location accelerated nearby residential development activity.
Third, the demolitions approved just before and the building permits approved just after the station location was announced suggest that redevelopment of industrial land near the station is concurrent with the building of the light rail system. Such concurrency of private and public development activity is a fundamental objective of land use planning. Finally, the imposition of the interim development restrictions does not appear to have slowed the rate of development activity. In fact, the increased certainty about the regulatory environment may have increased activity.
This five-year display of development events may be unique to the Orenco station area. Certainly, previous land use plans, sewer system investments and industrial expansion patterns have influenced development in the area. Nevertheless, the ability to track parcel-by-parcel activity in the county-wide database will enable in-depth examination of the extent to which dynamic and spatial relationships between development events and land use plans are significant and pervasive.
The regional and local governments of metropolitan Portland are engaged in an extensive planning endeavor to shape the extent, location and nature of urban development over the next four decades. As implementation proceeds, the information system will enable us to monitor the planning, regulation and development process and, for at least this metropolitan area, assess whether and how planning matters.
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The authors are affiliated with the Department of Urban and Regional Planning at the University of Illinois at Urbana-Champaign. Chengri Ding is a post-doctoral fellow specializing in the use of geographical information systems for urban economic analysis. Lewis Hopkins is professor and head of the department. Gerrit Knaap is associate professor, currently on sabbatical as a visiting fellow at the Center for Urban Policy and the Environment at Indiana University and a senior research fellow at the American Planning Association. Support for their research has been provided by the Lincoln Institute of Land Policy; the University of Illinois Research Board; the Metro of Portland, Oregon; Washington County, Oregon; the Tri-county Transportation District of Portland, Oregon; and the National Science Foundation.