Metadata: Census Geography 1990 - TLG Aligned; Blocks, Block Groups & Tracts

- none available -

Census Geography 1990 - TLG Aligned; Blocks, Block Groups & Tracts

This page last updated: 05/19/2003
Metadata created using Minnesota Geographic Metadata Guidelines

Metadata Summary

Originator	Metropolitan Council and The Lawrence Group (TLG)
Abstract	The Lawrence Group, under contract with Metropolitan Council, created a 1990 Census Bureau block polygon dataset for the Twin Cities Metropolitan Area (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott and Washington Counties). This dataset is coincident with and developed using the TLG Street Centerline and Landmarks databases where 1990 block boundaries fall on those features. For those block boundaries that are defined by features not included in TLG databases, TLG used other digital resources to generate these boundaries, such as orthophotography or additional features from city and county GIS databases. TLG used it's best judgement to digitize block boundaries when the block boundaries followed nonvisible features or street extensions. This is a MetroGIS Regionally Endorsed dataset.
Browse Graphic	none available
Time Period of Content Date	1990
Currentness Reference	1990 Census. Adjustment 1/17/01.
Access Constraints	None
Use Constraints	None
Distributor Organization	Metropolitan Council
Ordering Instructions	This dataset is distributed on the internet by clicking below after 'Online Linkage'. Doing so will tell your browser to download a 'ZIP' file which will contain the following: - ArcView shape files - metadata for the dataset (.htm) - NOTICE.RTF, an important notice about this dataset that can be read by any word processing software. Additionally, this dataset is available for direct use via one or more map services. More information about what a web mapping service is can be found at http://www.datafinder.org/services/ The specific map service and layer name for this dataset can be found by clicking the blue or green boxes under the map service column of the DataFinder Catalog at http://www.datafinder.org/catalog/ .
Distribution Liability	NOTICE: The Geographic Information System (GIS) Data to which this notice is attached are made available pursuant to the Minnesota Government Data Practices Act (Minnesota Statutes Chapter 13). THE GIS DATA ARE PROVIDED TO YOU AS IS AND WITHOUT ANY WARRANTY AS TO THEIR PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. The GIS Data were developed by the Metropolitan Council for its own internal business purposes. The Metropolitan Council does not represent or warrant that the GIS Data or the data documentation are error-free, complete, current, or accurate. You are responsible for any consequences resulting from your use of the GIS Data or your reliance on the GIS Data. You should consult the data documentation for this particular GIS Data to determine the limitations of the GIS Data and the precision with which the GIS Data may depict distance, direction, location, or other geographic features. If you transmit or provide the GIS Data (or any portion of it) to another user, it is recommended that the GIS Data include a copy of this disclaimer and this metadata.
Online Linkage	I AGREE to the notice in "Distribution Liability" above. Clicking to agree will begin the download process (See Ordering Instructions above for details.)

Full Metadata

Census Geography 1990 - TLG Aligned; Blocks, Block Groups & Tracts

Go to Section:
1. Identification Information
2. Data Quality Information
3. Spatial Data Organization Information
4. Spatial Reference Information
5. Entity and Attribute Information
6. Distribution Information
7. Metadata Reference Information


Section 1	Identification Information		Top of page
Originator	Metropolitan Council and The Lawrence Group (TLG)
Title	Census Geography 1990 - TLG Aligned; Blocks, Block Groups & Tracts
Abstract	The Lawrence Group, under contract with Metropolitan Council, created a 1990 Census Bureau block polygon dataset for the Twin Cities Metropolitan Area (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott and Washington Counties). This dataset is coincident with and developed using the TLG Street Centerline and Landmarks databases where 1990 block boundaries fall on those features. For those block boundaries that are defined by features not included in TLG databases, TLG used other digital resources to generate these boundaries, such as orthophotography or additional features from city and county GIS databases. TLG used it's best judgement to digitize block boundaries when the block boundaries followed nonvisible features or street extensions. This is a MetroGIS Regionally Endorsed dataset.
Purpose	The dataset was developed to have a 1990 census block database that is aligned to the TLG street centerlines and landmarks files, for use in analysis which utilizes both the census data and TLG street centerlines/landmarks. Blockgroup and tract datasets have been desolved from the block dataset. Additionally, since TLG's street centerline dataset is aligned within county rights-of-way for these counties, this dataset allows for parcel based analysis as it may pertain to census blocks, block groups and tracts. This dataset is a precursor to creating a 2000 census block dataset when the 2000 TIGER/Line files are released by the Census Bureau.
Time Period of Content Date	1990
Currentness Reference	1990 Census. Adjustment 1/17/01.
Progress	Complete
Maintenance and Update Frequency	As needed
Spatial Extent of Data	Twin Cities 7 County Metropolitan Area. This includes the counties of Anoka, Carver, Dakota, Hennepin, Ramsey, Scott and Washington in Minnesota.
Bounding Coordinates	-94.012 -92.732 45.415 44.471
Place Keywords	Twin Cities, Anoka County, Carver County, Dakota County, Hennepin County, Ramsey County, Scott County, Washington County
Theme Keywords	census, demographics, TIGER, blocks, block, block groups, block group, tracts, tract
Theme Keyword Thesaurus	None
Access Constraints	None
Use Constraints	None
Contact Person Information	Tanya Mayer, GIS Coordinator Metropolitan Council 390 Robert Street North St. Paul, Minnesota 55101-1805 Phone: 651-602-1604 FAX: 651-602-1674 E-mail: tanya.mayer@metc.state.mn.us
Browse Graphic	none available
Browse Graphic File Description	No browse graphic available
Associated Data Sets	1990 TIGER files from the Census Bureau TLG Street Centerlines - http://www.datafinder.org/metadata/NCompassRoads.htm TLG Landmarks - http://www.datafinder.org/metadata/NCompassLandmarks.htm

Section 2	Data Quality Information	Top of full metadata	Top of page
Attribute Accuracy	Each block has a census block number assigned to it that represents the original Census block in the TIGER/Line file. Several small water blocks that have radically changed since the 1990 census are not included in this. Due to differences in accuracy and geographical representation, there are 22 land Census blocks not included in this file (most of these are small islands) and 6 Census blocks assigned to more than 1 polygon. For a more detailed list see the TLG90Miss-Dup-blks.xls file. Other than these cases, a one-to-one correspondence has been confirmed between this dataset and the 1990 census data. For a complete description of Census Bureau block numbering, please reference the TIGER Technical Documentation (prior to 2000 TIGER) at www.census.gov/geo/www/tiger
Logical Consistency	Each county polygon file is topologically 'clean'.
Completeness	Entire seven county Twin Cities metro area is covered.
Horizontal Positional Accuracy	The positional accuracy of the dataset has not been tested under the National Standards for Spatial Data Accuracy. There are differing degrees of positional accuracy throughout the file. TLG adjusts the positional accuracy of the road boundary segments to available sources that are known to have a greater degree of accuracy than those used to generate the original data. However, in all cases (including instances where COGO line work has been the reference) TLG generalizes the segments to at most 4 feet in order to greatly reduce the number of vertices. Segments depicting road centerlines have been aligned or snapped to county provided COGO linework, Parcel data, street centerlines or right of ways. Where city boundaries are used as block boundaries, TLG has used the 'Counties and Minor Civil Divisions, Twin Cities Metropolitan Area' coverage which was developed by Metropolitan Council, Dakota, Hennepin, Scott & Washington Counties and the Minnesota Dept. of Transportation, unless there were differences from the 1990 census files due to annexations occurring after the 1990 Census boundaries were defined -- in which case, the 1990 MCD boundaries from TIGER were followed.
Lineage	The Lawrence Group, under contract with Metropolitan Council, created this 1990 Census Bureau block polygon dataset for the Twin Cities Metropolitan Area (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott and Washington Counties). This dataset is coincident with and developed using the TLG Street Centerline and Landmarks databases where 1990 block boundaries fall on those features. For those block boundaries that are defined by features not included in TLG databases, TLG used other digital resources to generate these boundaries, such as orthophotography or additional features from city and county GIS databases. TLG used it's best judgement to digitize block boundaries when the block boundaries followed nonvisible features or street extensions. After the data was received from TLG, Metropolitan Council GIS staff projected the coverages in to the current projection, added/standardized the attribute items, and created final shapefiles.
Source Scale Denominator

Section 3	Spatial Data Organization Information	Top of full metadata	Top of page
Native Data Set Environment	ArcInfo Version 8x, UNIX platform
Geographic Reference for Tabular Data	None
Spatial Object Type	Vector
Vendor Specific Object Types	arcs, nodes, polygons, label points
Tiling Scheme	One layer for entire seven county region in ArcView shape file format.

Section 4	Spatial Reference Information	Top of full metadata	Top of page
Horizontal Coordinate Scheme	UTM
Ellipsoid	GRS80
Horizontal Datum	NAD83
Horizontal Units	Meters
Distance Resolution
UTM Zone Number	15

Section 5	Entity and Attribute Information	Top of full metadata	Top of page

Entity and Attribute Overview

The polygon attribute table contains: 
(in addition to the standard ARC/INFO items) 
  
CO:         3 digit FIPS and state standard county Code; e.g. 163, 003  
  
TRACT:      6 digit Census Tract number 
  
BLOCK:      4 character Census Block number/code (alpha numeric) 
  
CTBLK:      10 character combined Census Tract and Block code with leading  
            zeros 
  
BLOCKGROUP: 7 digit Census Block Group number (Tract + 1st number of the block  
            code) 
  
COUNTY:     3 digit FIPS and state standard INTEGER county code; e.g. 163, 53 
  
CT:         6 character Census Tract number with leading zeros 
  
BLK:        4 character Census Block code 
  
  
BLOCK_1990 
  COL  ITEM NAME         WDTH OPUT TYP N.DEC  ALTERNATE NAME 
    1  AREA                8   18  F    5 
    9  PERIMETER           8   18  F    5 
   17  ANOKTLG#            4    5  B    - 
   21  ANOKTLG-ID          4    5  B    - 
   25  CO                  3    3  C    - 
   28  TRACT               6    6  I    - 
   34  BLOCK               4    4  C    - 
   38  CTBLK              10   10  C    - 
   48  BLOCKGROUP          7    7  I    - 
   55  COUNTY              3    3  I    - 
   58  CT                  6    6  C    - 
   64  BLK                 4    4  C    - 
  
TRACT_1990 
  COL  ITEM NAME         WDTH OPUT TYP N.DEC  ALTERNATE NAME 
    1  AREA                8   18  F    5 
    9  PERIMETER           8   18  F    5 
   17  ANOKTRACT#          4    5  B    - 
   21  ANOKTRACT-ID        4    5  B    - 
   25  CO                  3    3  C    - 
   28  TRACT               6    6  I    - 
  
BLKGRP_1990 
  COL  ITEM NAME         WDTH OPUT TYP N.DEC  ALTERNATE NAME 
    1  AREA                8   18  F    5 
    9  PERIMETER           8   18  F    5 
   17  ANOKBLKGRP#         4    5  B    - 
   21  ANOKBLKGRP-ID       4    5  B    - 
   25  CO                  3    3  C    - 
   28  BLOCKGROUP          7    7  I    - 
There are no arc attributes beyond the standard internal 
ARC/INFO attribute items.

Entity and Attribute Detailed Citation

Section 6	Distribution Information	Top of full metadata	Top of page
Publisher	Metropolitan Council
Publication Date	Unpublished material
Contact Person Information	Mark Kotz GIS Database Administrator Metropolitan Council Mears Park Centre, 390 Robert Street North St. Paul, Minnesota 55101-1805 Phone: 651-602-1644 FAX: 651-602-1674 E-mail: mark.kotz@metc.state.mn.us
Distributor's Data Set Identifier	Census1990TLG
Transfer Format Name	Arc Export files and ArcView Shape files
Transfer Format Version Number	ArcView: 3x
Transfer Size	7.8 MB for zip file.
Ordering Instructions	This dataset is distributed on the internet by clicking below after 'Online Linkage'. Doing so will tell your browser to download a 'ZIP' file which will contain the following: - ArcView shape files - metadata for the dataset (.htm) - NOTICE.RTF, an important notice about this dataset that can be read by any word processing software. Additionally, this dataset is available for direct use via one or more map services. More information about what a web mapping service is can be found at http://www.datafinder.org/services/ The specific map service and layer name for this dataset can be found by clicking the blue or green boxes under the map service column of the DataFinder Catalog at http://www.datafinder.org/catalog/ .
Distribution Liability	NOTICE: The Geographic Information System (GIS) Data to which this notice is attached are made available pursuant to the Minnesota Government Data Practices Act (Minnesota Statutes Chapter 13). THE GIS DATA ARE PROVIDED TO YOU AS IS AND WITHOUT ANY WARRANTY AS TO THEIR PERFORMANCE, MERCHANTABILITY, OR FITNESS FOR ANY PARTICULAR PURPOSE. The GIS Data were developed by the Metropolitan Council for its own internal business purposes. The Metropolitan Council does not represent or warrant that the GIS Data or the data documentation are error-free, complete, current, or accurate. You are responsible for any consequences resulting from your use of the GIS Data or your reliance on the GIS Data. You should consult the data documentation for this particular GIS Data to determine the limitations of the GIS Data and the precision with which the GIS Data may depict distance, direction, location, or other geographic features. If you transmit or provide the GIS Data (or any portion of it) to another user, it is recommended that the GIS Data include a copy of this disclaimer and this metadata.
Online Linkage	I AGREE to the notice in "Distribution Liability" above. Clicking to agree will begin the download process (See Ordering Instructions above for details.)

Section 7	Metadata Reference Information	Top of full metadata	Top of page
Metadata Date	05/19/2003
Contact Person Information	Tanya Mayer, GIS Coordinator Metropolitan Council Mears Park Centre, 390 Robert Street North St. Paul, Minnesota 55101-1805 Phone: 651-602-1604 FAX: 651-602-1674 E-mail: tanya.mayer@metc.state.mn.us
Metadata Standard Name	Minnesota Geographic Metadata Guidelines
Metadata Standard Version	1.2
Metadata Standard Online Linkage	http://www.gis.state.mn.us/stds/metadata.htm

This page last updated: 05/19/2003