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According to the U.S. census bureau, more than five billion people will live in urban areas by the year 2025. Are we prepared to handle all of these people? Not a chance. Urban design and planning issues are becoming more complex, and traditional planning and design techniques are inadequate for addressing many urban changes. In the old days, planners may have had to wait years to see whether their policies and decisions were successful. As a result, most municipalities were in a reactive mode, trying to solve the most immediate decisions at hand and too often ignoring long-term planning concerns.

Local governments must provide urban planning services to their constituents. Failure to do so leads to chaos and confusion. Roads would have no rhyme or reason. Natural resources would be totally overwhelmed by the built environment. Development would be out of control, roads would fall apart, trash would pile up on the streets and we would have no place to play or recreate.

Figure 1. GIS can combine data from multiple sources, as shown in this planning model of a section of Atlanta.

At the same time that urban planning issues are becoming more complex, citizens are no longer willing to let planning professionals make all of the decisions about their community. The days of planning in a black box are gone, and concerned citizens want to know not only what decisions are being made, but also how and why they are being made. Although it may take longer to make design and planning decisions, the likelihood of these decisions being implemented is much greater because of public involvement. As a result, GIS has become an essential tool in urban design and planning. The ability to create, modify, and analyze data is a major part of all decisions about urban communities. Thematic layers that show information such as land use, transportation corridors, census data, employment statistics and other types of information can be combined to study how decisions may affect a community (figure 1).

Urban Design and Planning

The urban landscape is in a constant state of flux. The next time you drive through a major city, pay attention to all of the construction. Urban designers and planners are the ones making decisions about how cities grow and develop. Urban planners typically determine policies and procedures, and urban designers work within this structure to give physical form to our cities.

Some of the activities that may occur during this process include transportation planning, emergency service planning, streetscape designs, routing studies, pedestrian circulation analysis, zoning analysis, land-use planning, view analysis, air- and light-pollution studies, urban vegetation management, demographic studies, historic preservation, security and wind and shadow analysis.

Urban designers typically start by conducting a thorough inventory and analysis to find out more about a site and its environment. The program for a project and subsequent design decisions are based in large part on this analysis. Urban designers need to have a thorough understanding of a site to ensure a successful project. The more detailed, complete and comprehensive the data, the better the analysis will be.

Figure 2. 3D models of urban areas (Tampa, Florida, is shown here) are readily available from many sources.

Most of the information needed to make decisions about urban communities at a broad level currently exists, but it needs to be analyzed and organized in a meaningful way. Integrated regional land-use databases are becoming more common, and dozens of sources provide most geospatial data needed for an urban planning project. Aerial and satellite images give urban planners the ability to view geospatial information and identify features on the ground, and this helps them make educated decisions.

3D models are effective for showing details of major urban projects, and 3D GIS data can be generated with technologies such as LIDAR and better CAD/GIS integration. Existing 3D models for most major cities are available from vendors such as CyberCity and GeoSim Cities, eliminating the need to create everything from scratch (figure 2).