Improving Census Boundary Information with Digital Mapping

Each year the U.S. Census Bureau asks local governments to participate in the Boundary Annexation Survey (BAS).  This survey gives the U.S. Census Bureau the most current geographic boundaries of the area the municipality serves. For many, like the Village of Woodridge, IL, it is an excellent opportunity to improve population estimates.

In previous years, this review process was manual, and municipalities used paper and colored pencils to demarcate their boundaries and neighboring borders. They had to note down any annexations, de-annexations, or boundary changes that occurred since the last BAS was conducted. 

Today, the Census Bureau encourages digital submissions of BAS materials using Geographic Information Systems (GIS). Instead of listing and drawing modifications by hand, GIS tools are used to quickly identify changes between village boundaries and census boundaries.  Using GIS for BAS submissions has benefitted the village in meaningful ways. It’s saved a great deal of staff time and effort, provided richer detail in identifying changes, and ultimately improved the population estimates provided by the Census Bureau.