2015 Boundary and Annexation Survey (BAS) Info

Here is our first communication for the 2015 BAS cycle. More information about BAS and the

WISE-Decade Consolidated BAS/Data Collection tool will follow soon!

This e-mail was sent to all Wisconsin County Clerks and Land Information Offices on 12/16/2014

Good Afternoon,

We would like to once again thank you and your staff for your assistance with the Local Redistricting effort following the release of the 2010 Census Data. The process of local redistricting in Wisconsin went relatively smoothly, thanks to all who were involved.

There were some challenges that local governments around Wisconsin faced with regard to the U.S. Census Bureau data. Wisconsin’s constitution requires that federal census data be used for redistricting. Over the last ten years, census data used for this process has dramatically improved, but it can be made better.

The Minor Civil Divisions information released by the U.S. Census Bureau needs to be updated by local governments on an annual basis to be accurate. The U.S. Census Bureau conducts the Boundary and Annexation Survey (BAS) annually to collect information about selected legally defined geographic areas. The BAS is then used to update information about the legal boundaries and names of all governmental units in the United States. The Census Bureau uses the boundary information collected in the BAS to tabulate data for the decennial and economic censuses, and annual estimates and surveys such as the Population Estimates Program and the American Community Survey.

To reduce the burden on local governments, and avoid the duplication of efforts, the Census Bureau offers consolidation agreements to counties that are interested in submitting boundary changes for the local governments (incorporated places and minor civil divisions) within their jurisdiction. The Consolidated Boundary and Annexation Survey (CBAS) program allows counties to report boundary and feature changes for some or all of these governments within their county.  Once a local government agrees to the consolidation, the local government will no longer receive BAS materials.  Instead, the county BAS respondent will be responsible for providing the Census Bureau with all boundary updates. For more information about the consolidated BAS (CBAS), please refer to the Census Bureau's website.

Currently, 48 Wisconsin counties have signed a consolidated (CBAS) agreement with the Census Bureau to participate in the 2015 CBAS program.

In an effort to help county and local governments streamline the process of submitting data to the U.S. Census Bureau, the Legislative Technology Services Bureau (LTSB) has developed software that quickly and easily compares census data and local datasets. This software was originally developed for Esri ArcGIS desktop, and creates all the necessary files needed to participate in the Census Bureau’s BAS and CBAS programs.

For BAS 2015, LTSB has created a web portal to access this software online. This software is currently available to any Wisconsin county or municipality free of charge.

It is LTSB’s goal to ensure every local government in the state has the ability to participate in the BAS program so that future releases of Census Bureau data (including the Census 2020 redistricting data) reflect the most accurate municipal boundaries possible for Wisconsin. Additionally, this online software will send accurate municipal boundaries to LTSB, enabling us to construct an updated, statewide layer of municipal and ward boundaries.

For more information on BAS, CBAS and the LTSB Data Integration tool please visit http://legis.wisconsin.gov/gis/bas

Information and documentation for this new system will be sent to individual County Clerks and Land Information Officers in the next few days.

Tony J. Van Der Wielen
Legislative Technology Services Bureau
GIS Manager

Liaison to the U.S. Census Bureau - Redistricting Data Program
Phone: 608-283-1817
E-mail: Tony.vanderwielen@legis.wisconsin.gov