As part of the ongoing Transportation and Regional Growth study, senior research fellow Carol Swenson of the Design Center for the American Urban Landscape presented her group’s current research project, "Impacts of Transit-supportive Growth," which focuses on compact mixed-use development integrating residential and commercial uses.

Much of the development in urban areas since the 1950s has been shaped by Americans’ love for—and reliance on—automobiles. Many urban planners, however, are interested in finding and promoting alternatives to the use of private automobiles, especially in planned development of urban and suburban areas experiencing rapid population growth.

Compact mixed-use development is a key component of many progressive land-use strategies, and is known variously as "the ‘Pedestrian Pocket’ concept," "New Urbanism," "Smart Growth," and "Transit-supportive Development." The common goal is to encourage a shift away from automobile-dependant development patterns. Credit for developing and popularizing this type of development is largely given to architect and community planner Peter Calthorpe, in his books Sustainable Communities and The Next American Metropolis.

Drawing inspiration from Calthorpe’s work on modeling community and regional development, Swenson’s research group is developing improved techniques for modeling transit-supportive growth patterns in neighborhoods and other urban "sub-areas." Their goal is to integrate this level of detail into regional models of growth and development.

In order to refine their sub-area model, the researchers are relying on detailed Geographic Information System (GIS) data for their primary study area, the North I-35W Corridor. Extending roughly from Roseville to Blaine in the inner Twin Cities suburbs, this area is defined by its proximity to interstate highway 35W and is currently experiencing population growth and rapid development. The GIS data for this area contains records of geospatial and economic information about land parcels in the study area drawn from Census records and other sources.

Analyzing the "walkability" of areas to be developed is an important component of her work, Swenson said. Walkability includes the availability of pedestrian routes as well as the convenience and usefulness of these routes. For example, residents may not use a well-made walking path if it takes too long for them to walk to shopping areas or transit access. The ability to walk to a transit access point is an important consideration in transit-supportive design.

When the sub-area model of transit-supportive growth is complete, it should give planners and researchers a powerful tool for developing transit-supportive growth strategies.