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Geographic information systems are
important tools for defining the social and environmental
contexts of urban design, planning, and architecture
by Bill McGarigle
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Photography: © Peter Vanderwarker
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A geographic information system (GIS),
a type of software system, enables a user to link any amount
or kind of data to a location with either geographic- or user-defined
coordinates. The data can be analyzed to find relationships
and trends, and results can be visualized in 2D or 3D map
layers, each representing a distinct group or class of information,
such as wetlands, wildlife habitats, crime statistics, or
demographics (much like the layers of a CAD file that represent
different elements of a building). The amount and type of
information that can be associated with a spatial or geographic
location in a GIS is virtually unlimited, and the data can
be integrated with imagery and other objects, stored in databases,
and distributed as interactive maps via the Internet or other
electronic means.
Once as unwieldly as first-generation word processors, GIS
has been considerably tamed through automated operations and
Windows-like interfaces. High-end systems and complex analyses
are still the domain of specialists, but third-party developers
now build custom interfaces that give nontechnical users access
to GIS tools for developing maps and analyzing information.
The last few years have witnessed the growing use of GIS
as a tool for defining the context in which we build structures
and develop cities and for understanding the effects of proposed
designs on their surroundings. “If our aim is to build
sustainable designs,” says Patrick Moore, director of
Integral GIS, in Seattle, “we need a larger view of the
world. And there’s no other tool in town that can give
us that like GIS.” Case studies illustrate these issues,
as well as the role and diversity of GIS applications in urban
design, planning, and other architecture-related disciplines.
Defining environmental impacts
In Los Angeles, GIS was used to conduct an environmental-justice
analysis to determine whether distribution of environmental
impacts from a proposed expansion of the Los Angeles International
Airport (LAX) would fall predominately on minority and low-income
communities. The study was undertaken as part of the environmental-impact
statement prepared for the LAX master plan. It was conducted
by PCR Services Corporation, an environmental consulting firm
in Santa Monica, California.
Using demographic data from the census and from federal guidelines,
GIS specialists at PCR first identified the socioeconomic
profiles of several communities close to LAX. Onto these they
overlaid environmental-impact data in separate, thematic layers.
PCR planner Paulette Wills said this data—which centered
primarily on aircraft and construction noise, traffic patterns,
and air quality—was gathered from other parts of the
statement. “Through the overlay process,” Wills
explained, “we could see who the affected populations
were, and in what communities [they reside].” The team
also overlaid noise contours onto maps showing individual
property boundaries to determine the exact numbers of households
and populations that would be affected by aircraft noise.
The final phase involves development of an environmental-
justice program designed to mitigate or offset adverse impacts
of the expansion—such as excessive noise, traffic congestion,
and decreased air quality. Such a program might include increased
public transportation, or installing air filters to improve
indoor air quality in affected buildings. Whatever the outcome,
GIS will have had a major role in defining the social and
environmental contexts for the public review and administrative
processes that follow, by helping decision makers analyze
where to implement the various program elements.
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