What is the Boundary and Annexation Survey?

The U.S. Census Bureau conducts the Boundary and Annexation Survey (BAS) annually to collect information about selected legally defined geographic areas. BAS is used to update information about the legal boundaries and names of all governments. Each year, all functioning legal government are surveyed.

The U.S. Census Bureau uses the boundaries collected in BAS to tabulate data for various censuses and surveys including the decennial census, American Community Survey, and Population Estimates Program. It also uses the legal boundaries collected through BAS to support several other programs such as Congressional and State Legislative redistricting, the Economic Census, the Geographic Update Population Certification Program, and the Special Census program. For additional information, see the BAS Methodology page.

What is a State BAS Agreement?

The purpose of the BAS agreements is to coordinate information sharing and resources between the U.S. Census Bureau and state and county governments in collecting boundary information. Through these agreements with state and county governments, the U.S. Census Bureau aims to reduce the duplication of effort across the various levels of government as well as the cost burden associated with the annual BAS.

Wisconsin participates in a State BAS Agreement. By law, all local governments are required to report all boundary changes to a state agency, which in Wisconsin’s case is the Legislative Technology Services Bureau (LTSB). LTSB reports boundary changes for all incorporated places, minor civil divisions (MCDs) if applicable, and counties within Wisconsin to the annual BAS.

The U.S. Census Bureau will still send information to the Highest Elected Official (HEO) within each jurisdiction. If there are any legal boundary changes missing, the HEO is encouraged to reach out to their respective County Land Information Office to include that update within their next State BAS submission.

Why did we create the BAS Data Collection Application?

Wisconsin local and legislative redistricting is mandated by our state's constitution to use U.S. Census tabulated geography for creating districts. Historically, most counties and municipalities have not participated in BAS; therefore Census TIGER lines do not correctly align with local data in Wisconsin. To minimize the effort it takes for locals to submit data to the Census, we had previously created a desktop ArcGIS ArcMap Add-In that was widely well-received, but providing data and application updates for the user base has been difficult. To further minimize local efforts, and eliminate these types of issues, we created a web-based application utilizing ArcGIS Server and the ArcGIS JavaScript API.

What does the BAS Data Collection Application do?

The BAS Data Collection Application within the LTSB GeoData Collector compares U.S. Census Bureau geography with local municipal data to generate a symmetrical difference. It automatically enters the required attributes, filters for Census defined acceptable changes, and flags potential annexations not yet submitted to, or absorbed by, the U.S. Census Bureau. The application pulls legal boundary changes submitted to DOA Municipal Data System: https://mds.wi.gov/View/Ordinances. Those annexation documents can then be selected and associated to the specific boundary change for the U.S. Census Bureau to reference. This will not change your local dataset; it will only compare it to the U.S. Census Bureau’s data. Each county will submit their data to the LTSB GeoData Collector BAS Application, and LTSB will submit all statewide changes to the Census Bureau.

If you need help using the LTSB GeoData Collector BAS application, please refer to our help documentation.

Wisconsin’s Local Redistricting Group is pleased to announce the Local Redistricting Training Webinar Series

WISE-LR is a web application developed by the LTSB to assist local governments and counties with local redistricting in Wisconsin. The application was designed specifically to accommodate the rules and the process of local redistricting outlined in Wisconsin State Statutes. WISE-LR allows local officials, or their delegates, to create, analyze, and share county supervisory plans, municipal ward plans, and aldermanic plans with accurate demographic data. Every Wisconsin County Clerk, County Land Information Officer, and Municipal Clerk will be sent credentials and instructions on how to log-in to the WISE-LR Local Redistricting Software. If you need help using the WISE-LR application, please refer to: WISE-LR Help Documentation.

As with previous versions, the primary purpose of WISE-LR is for local government officials to draw their ward and supervisory districts. Additionally, the site may be used by any geographic boundaries where population matters! This may include school districts, special tax districts, aldermanic districts or many others. The system is designed to allow easy collaboration, data sharing, and data file creation as a module of WISE-Decade.