County Consolidated BAS – Allows a County to legally submit all (or most) of the municipal boundaries to the Census Bureau. New LTSB Tools and Support

1. Updating Census Tiger Geography
Creating and Maintaining a Current MCD and Municipal Ward Layer
Tony J.Van Der Wielen
GIS Manager
Legislative Technology Services Bureau
Sarah Kemp
Associate Researcher
UW Applied Population Laboratory

2. The Problem: Census Municipal Boundaries are not
Spatially Accurate
• After modernization the spatial accuracy of TIGER line files has been updated to
+/- 7.6 meter (+/- 25 feet)
– In many areas the spatial accuracy of TIGER is better than +/- 5 meters.
• Municipal boundaries are still inaccurate.
– The Census Bureau relies on all communities to participate in the Boundary Annexation Survey (BAS) on
a yearly basis to update municipal boundaries.
– Local communities are the only entities that can legally update the municipal boundaries in TIGER (1,900
communities).
– BAS is performed every year between January and March.
• Why is this a problem?
– Local, Legislative and Congressional Redistricting
– Elections
– These boundaries are used by Federal and State governments/programs

3. A Possible Solution: County Consolidated BAS
• County Consolidated BAS
– Allows a County to legally submit all (or most) of the municipal boundaries to the Census Bureau
• This can be done electronically with existing GIS files already being maintained at the county
• Requires municipalities to “sign off”
• Allow the Census Bureau to work with fewer government entities
• Census will provided template forms and detailed instructions
• August 1st Deadline for 2013 BAS
• LTSB Tools and Support
– WISE-LR
• Data management tool to continually maintain municipal ward datasets
• Statewide Municipal Ward and Municipal Boundary generation
– LTSB Data Integration Tool – ArcGIS Mxd file
• Tool to compare Census BAS GIS files with local datasets
• Generates a change file that can be submitted directly to the Census Bureau for spatial correction of municipal
boundaries
• Municipal annexation processing – Will include annexation in statewide layer and will process for BAS.

4. LTSB BAS Data Integration Tool

7. Project Resources
US Census Bureau – Boundary Annexation Survey
http://www.census.gov/geo/www/bas/bashome.html
Gail A. Krmenec – Supervisory Geographer
630-288-9258
Gail.a.krmenec@census.gov
Legislative Technology Services Bureau
http://legis.wisconsin.gov/LTSB/BAS
Tony J. Van Der Wielen – GIS Manager
608-283-1817
Tony.vanderwielen@legis.wi.gov
Applied Population Laboratory
http://www.apl.wisc.edu/
Sarah Kemp – Associate Researcher
608-265-6189
Kemp@wisc.edu