Keep Me Informed

Community Mapping

What Is It?

Those working in community revitalization frequently wrestle with questions such as:

  • What is the mix of renters and homeowners in my community?  Should my organization focus on creating affordable rental or owner-occupied units?
  • Where in the region is job growth occurring?  Does my community have access to these jobs?
  • Who owns the most slum housing, tax delinquent properties, or properties with code violations in my neighborhood?
  • What are the land use implications of new transportation developments like rail lines and freeways on my community?

Community Mapping
A Visual Narrative

Community mapping is a vibrant way of telling a neighborhood's story. IUt can highlight the rich array of neighborhood assets, analize the relationship between income and the location of services, or document vacant lots and buildings.

These questions-along with countless others about socio-economic conditions, development opportunities, and neighborhood change-can be answered through the use of community mapping. Mapping is the visual representation of data by geography or location, the linking of information to place.  Community mapping does this in order to support social and economic change on a community level. Mapping is a powerful tool in two ways: (1) it makes patterns based on place much easier to identify and analyze and (2) it provides a visual way of communicating those patterns to a broad audience, quickly and dramatically.  The central value of a map is that it tells a story about what is happening in our communities.  This understanding supports decision-making and consensus-building and translates into improved program design, policy development, organizing, and advocacy.


The products of community mapping can take several forms: Context maps represent one or a few variables by a broad unit of geography (e.g., income level by census tract).  Display maps are more complex, illustrating single or multiple variables by smaller units of geography (e.g., the condition of individual properties at the parcel level.)  Analytical maps are the most complex, layering and analyzing multiple variables by various levels of geography. An analytical map might combine income at the census tract level and condition of individual properties at the parcel level and highlight how the two variables relate to each other.

 

Context

Display

Analytical

Context: Concentration of African American population by census tract. Milwaukee, WI (Endeavor Corporation)

Display: Lead exposure risk levels by property parcel Minneapolis, MN (Longfellow Community Council)

Analytical: Property parcels with code violations and concentration of Latino population by census tract Los Angeles, CA (Neighborhood Knowledge Los Angeles)


(Please see the map gallery for more examples of cutting-edge community mapping applications used to promote equitable development.)
Community maps can be hand drawn or computer generated.  Some of the more complex, computer-generated maps are also interactive, allowing users to analyze data and create maps based on the locations and kinds of data that interest them.

Community Mapping and Geographic Information System (GIS)

The terms community mapping and GIS are often used interchangeably.

We define community mapping as the entire spectrum of maps created to support socal and economc change at the community level, from low-tech, hand-drawn paper maps to high-tech, database driven, internet maps that are dynamic and interactive.

Geographic Information System (GIS), as defined by US Geological survey, are "computer systems capable of assembling, storing, manipulating, and displaying geographically referenced information data identified according to their locations." GIS not just about making maps or visually displaying data, it is tool for analyzing many layers of data. allowing users to see information in new ways. GIS projects map everything from demographics to natural resources, from transpotation networks to community condition. They can illustrate data for a single point in time or show changes over time.

We use the term GIS to discribe the type of software used, and "GIS application" to discribe the way a perticular organization sets up or programs that software in order to analyze and map its own data.

Again, data being displayed by geography is the basis of all GIS. The graphics bellow illustrates various data types and levels of geography that are relevent to community revitalization and can be entered into a GIS application. The resulting computerized map can show several layers of information simultaneously, illustrating the relationship between variable like vacancy rates and crime or hack cashing facilities and household income.

Data x Geographic Units = Maps
Property Ownerships
Land Use
Housing Characteristics
Vacancy Indicator
Tax Information
Demographic/Census Data
Environmental Conditions
Property Parcels
Census Tracts
Zip Codes
Neighborhoods
Council/School Distracts
Cities
Countries
States
Data/Information analyzed relative to geographiy and displayed visually.

Increasingly, community practitioners are using computer software such as Geographic Information Systems (GIS) (see sidebar) to carry out community mapping projects.  Other technological advances, such as handheld computers and public access to the government's Global Positioning System (GPS), are also transforming the world of community mapping.
This tool is an overview of community mapping, with an emphasis on how mapping is used to support equitable development.  It offers general guidelines for engaging in mapping and discusses the benefits, the possible types of analysis, how various approaches work, and the scale and cost of different efforts.  It reviews a range of community mapping efforts, from low-tech to high-tech and from communities around the country, with an emphasis on projects using GIS.

Last Updated: April 2002