Administrative Services

Blocks

Metadata:

Identification_Information:
Citation:
Citation_Information:
Originator:
Allegheny County Division of Computer Services Geographic Information Systems Group
Publication_Date: 2002
Title: Blocks
Geospatial_Data_Presentation_Form: vector digital data
Series_Information:
Series_Name: Base Data
Publication_Information:
Publication_Place: Pittsburgh, PA
Publisher:
Allegheny County Division of Computer Services Geographic Information Systems Group
Description:
Abstract:
Derived from original MAPINDX: Map Index Sheets from Block and Lot Grid of Property Assessment and based on aerial photography, showing 1983 datum with solid line and NAD 27 with 5" grid tics and italicized grid coordinate markers and outlines of map sheet boundaries. Each grid square is 3500 x 4500 feet. Each Index Sheet contains 16 lot/block sheets, labeled from left to right, top to bottom (4 across, 4 down): A, B, C, D, E, F, G, H, J, K, L, M, N, P, R, S. The first (4) numeric characters in a parcelID indicate the Index sheet in which the parcel can be found, the alpha character identifies the block in which most (or all) of the property lies.
Purpose:
Data was developed as part of the effort to establish large scale base data to support a Geographic Information System in Allegheny County
Supplemental_Information:
Data meets or exceeds map accuracy standards in effect during the spring of 1992. Baymont Technologies held a contract with Allegheny County and Equitable Resources to fly the County and Equitable Resources Service Area to produce planimetric data. Subcontractors for the project included: Howard Hartman and Associates who provided ground control for the flight; Aerial Data Reduction (ADR) who performed the photography; Centec and Baker Engineers who digitized the data. Photography was produced at a scale of 1"=1500'. Mapping was stereo digitized at a scale of 1"=200'. Digital Orthophotos were not included as a deliverable.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: Spring 1992
Ending_Date: Spring 1993
Currentness_Reference:
Original data was derived from aerial photography flown in the spring of 1992 for the eastern half of the County and the spring of 1993 for the western half of the County.
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -80.374588
East_Bounding_Coordinate: -79.669315
North_Bounding_Coordinate: 40.685169
South_Bounding_Coordinate: 40.180013
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: boundaries
Theme_Keyword: imagery, base maps, earth cover
Theme_Keyword: location
Place:
Place_Keyword: PA
Place_Keyword: Pittsburgh
Place_Keyword: Clairton
Place_Keyword: Duquesne
Place_Keyword: McKeesport
Access_Constraints: Call for Details
Use_Constraints:
All parties acknowledge that the data is for informational purposes only. The existing digital data is shipped as is and there is no guarantee as to its completeness or accuracy. Allegheny County Division of Computer Services Geographic Information Systems Group is not responsible for any reliance upon said data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Allegheny County Division of Computer Services Geographic Information Systems Group
Contact_Position: GIS Manager
Contact_Voice_Telephone: 412 350-7447
Contact_Facsimile_Telephone: 412 350-4754
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535
Cross_Reference:
Citation_Information:
Originator:
Allegheny County Division of Computer Services Geographic Information Systems Group
Data_Quality_Information:
Logical_Consistency_Report:
Data was subject to QA/QC process at the time it was recieved (1992-1996). Data was produced in a series of 1,362 tiles measuring about 4,600 feet X 3,500 feet. Tiles are numbered in a clockwise spiral fashion starting with #1 at the point in downtown Pittsburgh. Each tile contains 16 Blocks. Data from most tiles was delivered by 1996 when GIS Operations ceased in Allegheny County, with the exception of one person in the Health Department.
Completeness_Report:
There is data for all of the municipalities in the county, with some holes in some layers. It is estimated that between 16 and 91 tiles of data might be missing in a layer.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Geodetic reference framework was created using NAD 83, the result of the latest geodetic readjustment by NGS at the time. Photography was produced at a scale of 1"=1,500'. Mapping was stereo digitized at a scale of 1"=200'. Map data meets or exceeds map accuracy standards in effect during the spring of 1992.
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: +/- 5 feet
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Geodetic reference framework was created using NAGVD 29 in conformance with the monument densification program outlined in the County of Allegheny Geodetic Control Report of 1991.
Quantitative_Vertical_Positional_Accuracy_Assessment:
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator:
Allegheny County Division of Computer Services Geographic Information Systems Group
Publication_Date: 1992
Title: Baymont Tiles, Base Data
Other_Citation_Details:
Data was created in ArcInfo Coverages on Sun 4/330 Workstations in a distributed environment.
Source_Scale_Denominator: 200"
Type_of_Source_Media: digital tape media
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 1992
Ending_Date: 1993
Process_Step:
Process_Description:
During Y2K efforts of 1999-2000, data was transferred to Microsoft NT Server running ArcInfo 7 and was made available to county users across the network from a single location.
Process_Date: 2000
Process_Step:
Process_Description: Tiles edgematched to create a single seamless County coverage
Process_Date: 2000-2003
Process_Step:
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: C:\DOCUME~1\t094246\LOCALS~1\Temp\xml685.tmp
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: W:\datashare_exports\shapefiles\index.shp.xml
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: W:\datashare_exports\shapefiles\blocks.shp.xml
Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: G-polygon
Point_and_Vector_Object_Count: 21665
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Point
Point_and_Vector_Object_Count: 1756
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Label point
Point_and_Vector_Object_Count: 30990
Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
Standard_Parallel: 39.933333
Standard_Parallel: 40.966667
Longitude_of_Central_Meridian: -77.750000
Latitude_of_Projection_Origin: 39.333333
False_Easting: 1968500.000000
False_Northing: 0.000000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000512
Ordinate_Resolution: 0.000512
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: blocks
Attribute:
Attribute_Label: FID
Attribute_Definition: Internal feature number.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: TILE
Attribute:
Attribute_Label: TILENUM
Attribute:
Attribute_Label: BLOCKS_
Attribute:
Attribute_Label: AREA
Attribute:
Attribute_Label: BLOCKS_ID
Attribute:
Attribute_Label: PERIMETER
Attribute:
Attribute_Label: TILEBLOCK
Attribute:
Attribute_Label: BLOCK
Attribute:
Attribute_Label: TILEBLKNUM
Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Allegheny County Division of Computer Services Geographic Information Systems Group
Contact_Position: GIS Manager
Contact_Address:
Address_Type: mailing and physical address
Address: 621 County Office Building
Address: 542 Forbes Avenue
City: Pittsburgh
State_or_Province: PA
Postal_Code: 15219-2952
Country: USA
Contact_Voice_Telephone: 412 350-4774
Contact_Facsimile_Telephone: 412 350-4754
Resource_Description: Call for Details
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Transfer_Size: 66.284
Ordering_Instructions: Call for Details
Metadata_Reference_Information:
Metadata_Date: 20071031
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Allegheny County Division of Computer Services Geographic Information Systems Group
Contact_Position: System Supervisor, GIS
Contact_Address:
Address_Type: mailing and physical address
Address: 621 County Office Building
Address: 524 Forbes Avenue
City: Pittsburgh
State_or_Province: PA
Postal_Code: 15219-2952
Country: USA
Contact_Voice_Telephone: 412 350-4774
Contact_Facsimile_Telephone: 412 350-4754
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage:<http://www.esri.com/metadata/esriprof80.html>
Profile_Name: ESRI Metadata Profile
Generated by mp version 2.8.6 on Wed Oct 31 14:37:01 2007