Perceived Usefulness of Scenario and Visualization Tools for Planning, Design, and Impact Analysis of Development around Transit Stations

Todd Graham, Metropolitan Council
Michael D. Greco, University of Minnesota Center for Urban and Regional Affairs
David G. Pitt, University of Minnesota Department of Landscape Architecture

“Corridors of Opportunity” is an initiative to promote sustainable, vibrant, and healthy communities framed around a transit network in the Twin Cities, Minnesota, metropolitan region. The initiative is funded by a Sustainable Communities Regional Planning Grant from the U.S. Department of Housing and Urban Development, with additional funding from Living Cities, a collaboration of foundations and financial institutions. The original Corridors of Opportunity work plan included evaluation of scenario and visualization tools to equip and prepare transit corridor initiatives and planners in the use of planning support technologies for planning, design, and analysis of neighborhood-scale development around future and existing transit stations. The objectives of this work included:

•Successful adoption and implementation of scenario and visualization tools by planners, community leaders, and others.
•Improved public understanding of design and plan alternatives.
•Improved community participation experiences in targeted corridors.
•Improved comparability and replication of planning processes among corridors.

The Twin Cities Metropolitan Council, along with researchers from the University of Minnesota, studied three current-generation planning support solutions: CityCAD, CommunityViz, and Envision Tomorrow (paired with Google SketchUp for visualization). The study included use-testing, identification of criteria for technology evaluation, and focus groups to demonstrate and discuss applicability of the systems for local station-area planning.

Four focus groups were conducted with land-use and transportation planners (14 participants) and community organizers and representatives (11 participants). Participants were shown 20-minute demonstrations of each software system. They were then asked to evaluate the utility of each system for early-stage, neighborhood-scale planning in a public-participation context relative to (1) conceptual development of neighborhood plans, (2) visualizations of experiential conditions resulting from plan design, and (3) evaluation of development impacts on a range of measures.

Several findings emerged from thematic analysis of focus group responses. First, although participants identified specific strengths and weakness of each software program, there was not one clearly preferred system. In general, CityCAD was recognized for its capacity to generate crude, but quick, two- and three-dimensional representations of alternative site designs. Participants appreciated but were not entirely satisfied with the visualization capabilities built into CommunityViz, as well as its set of metrics for evaluating impacts of development. Envision Tomorrow was recognized for its capacity to more comprehensively evaluate development impacts and provide such measures in spreadsheets. However, Envision Tomorrow did not have 3-D visualization as a built-in feature, a significant inconvenience for technician users of the system.

Community representatives and planners saw potential for plan scenario and visualization technology to focus discussion and create shared understanding of design and plan alternatives. However, both groups were skeptical that design exploration could (or should) be undertaken in public meetings, workshops, or other participatory settings.

The Metropolitan Council’s initial objective was to equip community groups to adopt and use planning or urban design tools. In the focus groups, however, few community representatives expressed interest in being direct, hands-on users of such tools. Both groups preferred that preliminary planning, design, and impact analysis be led by project sponsors or planning agencies before engaging the public. Planners, for their part, found the proposed tools to be limited in functionality. They were more interested in using scenario and visualization tools for impact analysis and data management of detailed planimetric data and infrastructure plans, ideally with digital output that would be useable by civil engineers, architects, and other technical professionals involved over the life-cycle of a station-area plan.

Community representatives (and, to a lesser degree, planners) emphasized that the value of visualization tools is highly context-dependent, and will vary depending on public participants’ knowledge of planning and design concepts, language barriers, and expectations about the realism of computer visualizations. Some planners and community representatives noted that the crude or “cartoonish” nature of the visualizations risked underwhelming or insulting the capacity of the public. Participants of both groups preferred that technology solutions deliver finished, near-virtual visualizations and clearly represent measurement of plan performance and outcomes. Some planners also expressed concern that public audiences might be distracted by the technology or focus disproportionately on minor design details.

Planners and community representatives expressed interest in and concern about the sources and types of data required to use the demonstrated planning solutions. Planners were concerned about the data demands of the programs, as well as about the potential for inaccurate or unreliable data to skew outcomes. For community representatives, the data issue revolved more around trust; some were wary about the sources of and hidden assumptions inherent in the data used to populate the models.

Current-generation planning support systems are increasingly capable of drafting and presenting alternative plans, and of tracking the attributes of allowable land uses, potential buildings, and infrastructure. The Metropolitan Council and University of Minnesota research team found that current technologies can aid public understanding of urban design and station-area planning, and thus improve the quality of public discussion and deliberation. Still, the technologies are not a panacea. The construction and presentation of plan scenarios and visualizations involves a complex balancing act. Some of the trade-offs are technical: public audiences may expect more extensive measurement and representation of plan outcomes, and more realistic—even photo-realistic—visualization. Such deliverables require more extensive and complex tools, and higher skill levels, than may be available to planners. Other issues are identical with those faced by planners for decades. Community values drive the creation of optimal small-area plans. It is often difficult to approximate community preferences through a process that must simultaneously address and balance competing technical, policy, fiscal, and regulatory demands.

The corresponding author, Michael Greco, can be reached at mgreco@umn.edu.