Introduction to the Digital BAS

1. Introduction to the Digital BAS

2. Overview • What is the MAF/TIGER Database? • What is included in the Digital BAS package? • What is the difference between Digital BAS and MTPS? • What are some tips for updating the BAS materials digitally? • How do I return my digital submission to the Census Bureau? • MTPS and Digital BAS Demo

3. MAF/TIGER Database • Master Address File/Topologically Integrated Geographic Encoding and Referencing (MAF/TIGER Database) • Rather than having one layer for each feature class, all information is stored in a single layer • Database is constructed of nodes, edges, and faces • Each edge can represent the boundary for multiple geographies: • Place, County, Tract, School District, Voting District Boundaries, etc. • Changing a place boundary can affect boundaries for other geographies

4. Topological Relationship Edges CensusTract Incorporated Place School District Integrated Layer

5. MAF/TIGER Database - Edges

6. MAF/TIGER Database – County Subdivisions

7. MAF/TIGER Database – School Districts

8. MAF/TIGER Database – Voting Districts

9. BAS Package Materials • Letter and Form • Contains your username for MTPS: bas • You do not need to fill out the form when responding digitally • MAF/TIGER Partnership Software CD • Data and Respondent Guide CD/DVD • Contains shapefiles for use with Digital BAS and MTPS • Contains respondent guides for Digital BAS and MTPS • No Change postcard

10. Digital BAS • Participants use their own GIS to create the digital BAS submission file: • Create change polygons representing the difference between local boundaries and the Census Bureau’s boundaries • Attribute each polygon with the required information • We send out ESRI shapefiles (.shp), but any GIS that can read/convert shapefiles may be used • It is important to read the Digital BAS respondent guide carefully to make sure you include all required information

11. MAF/TIGER Partnership Software - MTPS • As an alternative to another GIS software, participants may use the Census Bureau’s free MTPS to create the digital BAS submission file. • The MTPS forces the user to include the required attribute information for the boundary and feature updates. • The software handles the data conversion and compresses all of the output files together for you to create the final digital BAS submission file. • MTPS is appropriate for users who are not experienced in GIS or do not have their own GIS software.

12. Digital Update Guidelines • We cannot accept a local GIS file to “replace” our existing boundary information: • Must have legal documentation and effective dates for all legal boundary changes • We must keep record of all changes made for reference purposes • Topologically integrated database • Snap to existing census geography where appropriate: • Use existing census roads, rail, and hydro wherever possible (if our river and your river differ spatially by 10 feet, snap to our river)

13. Data Projections • Census files are in GCS NAD 83 format and can be projected into any local coordinate/projection • Most GIS software packages will allow users to transform file coordinate systems and projections • In ArcGIS, use the Project tool in ArcToolbox

14. Types of Boundary Updates • Annexations & Deannexations • Boundary Corrections • Geographic Corridors & Offsets • New Incorporations

15. Other Acceptable Updates • Linear Features • Point Landmarks • Area Landmarks • Address Ranges

16. Annexations and Deannexations • These are referred to as legal boundary changes: • Large change polygons are most likely annexations • Change polygons are sometimes not contiguous with your boundaries • A change to the entity’s boundary through a legal action: • Ordinance/Resolution • Local law or Court order • State level action • Must always include the following in lieu of the actual legal documentation: • Effective Date • Ordinance/Resolution Number • Acreage required for Georgia entities

17. Annexations and Deannexations (Attribute Table) • Must enter the following in the change polygon attribute table for each annexation/deannexation: • Name of the affected entity • The effective date • The document/authorization number (Ex: ordinance or resolution #) • Change type is coded A for annexation or D for deannexation

18. Boundary Corrections • Minor fixes to the entity boundaries due to drafting or plotting errors. • Should follow the general shape of the current boundary. • Are neither annexations nor deannexations, although they may be fixing the depiction of previous annexations or deannexations. • Boundary corrections DO NOT require legal documentation.

19. Boundary Corrections (Attribute Table) • Must enter the name of the affected entity in the Name field • Enter “B” in the Change Type field to designate a Boundary Correction • In the Relate field enter the following: • IN if the territory needs to be in the affected entity • OUT if the territory needs to be out of the affected entity

20. Geographic Corridors • An area that only includes road surface and right-of-way and does not contain any structures addressed to either side of the road. • The Census Bureau will geocode addresses based on the centerline of road. • There are two types of geographic corridors 1.) Road through unincorporated space 2.) Road through incorporated space • BAS participants should recommend the creation of a geographic corridor ONLY when this coding would result in addresses being assigned to the wrong entity.

21. Geographic Corridors Example: Road through an unincorporated place In this example, the houses are in unincorporated county, while the road ROW has been annexed into an incorporated place. Without a corridor, the housing units along this road would be included in the incorporated place.

22. Geographic Offset • An area claimed by an entity that is only on one side of the road and does not include any structures addressed to the right-of-way on that side of the road. • Policy towards Geographic Offsets: • We prefer that you do not show a boundary on a front lot line. • If houses on the far side of the road should be in your jurisdiction, please represent the boundary on the rear lot line. • If houses on the far side of the road should NOT be in your jurisdiction, please snap the boundary to the centerline. • An offset should be used if you must show the boundary on the front lot line. • Using one of these techniques insures that the residential structures will be assigned to the correct geography.

23. Geographic Corridors and Offsets Incorporated Places We prefer that you snap the boundary to the centerline as offsets are difficult to maintain. If offsets are not coded as such, your boundary will be snapped. A B

24. New Incorporations For all new incorporations, we need the following: • The official name of the new incorporation • The name and phone number of a contact person for processing • A copy of the official papers of incorporation • The effective date • The mailing address • The name of the HEO of the new incorporation • The name of the BAS contact of the incorporation, if different from the HEO

25. Street Features • Street features can be added or edited in MTPS or ArcGIS • These are not required unless they serve as a boundary

26. Data Dictionary

27. Reporting the Data to the BAS • Compress your change polygon shapefile and any other edited shapefiles into a zip file • If you are using MTPS, the software will automatically zip the required shapefiles after you are done. • Upload the zip file onto the Census Bureau’s FTP site. • Instructions for the site are provided in the Respondent Guides. • The MTPS submission file can be quite large. If you are having issues uploading the file onto the FTP site, simply remove all the files that do not contain the BAS prefix in the name, and try uploading again.

28. Digital BAS DemonstrationArcGIS&MAF/TIGER Partnership Software (MTPS)