Administrative Services

Street Centerlines

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator:
Allegheny County Division of Computer Services Geographic Information Systems Group
Publication_Date: 2006
Title: Street Centerlines
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
Other_Citation_Details:
Data was updated as a result of a flyover in the spring of 2004. A database field has been defined for all map features named "Update Year". This database field will define which dataset provided each map feature. Map features from the current map will be set to "2004". The earlier dataset map features the earlier dataset map features used to supplement the area near the county boundary will be set to "1993". All new or modified map data will have the value for "Update Year" set to "2004".
Online_Linkage:
\\GISSQL01\GISData\gisstaff\Data_Clip\Shapefiles_for_Clip\streetcl.shp
Description:
Abstract:
This dataset contains street centerlines for vehicular and foot traffic in Allegheny County. Street Centerlines are classified as Primary Road, Secondary Road, Unpaved Road, Limited Access Road, Connecting Road, Jeep Trail, Walkway, Stairway, Alleyway and Unknown.

A Primary Road is a street paved with either concrete or asphalt that has two (2) or more lanes in each direction. A Secondary Road is a residential type hard surface road, or any hard surface road with only one (1) lane in each direction. An Unpaved Road is any road covered with packed dirt or gravel. A Limited Access Road is one that can only be accessed from a Connecting Road such as an Interstate Highway. A Connecting Road is a ramp connecting a Limited Access Road to a surface street. A Walkway is a paved or unpaved foot track that connects two (2) roads together. Walkways within College Campuses will also be shown. Recreational pedestrian trails and walkways through parks and wooded areas are not considered transportation and will not be digitized during this update. Walkways will not have an Edge of Pavement feature. A Stairway is a paved or wooden structure that connects two (2) roads together. Recreational pedestrian trails and walkways through parks and wooded areas are not considered transportation and will not be digitized during this update. An Alleyway is a road, usually narrower than a Secondary Road that runs between, but parallel to, two (2) Secondary Roads. Generally, Outbuildings will be adjacent to Alleyways. A Jeep Trail is a vehicular trail used for recreation. A Jeep Trail will not have an associated edge of pavement feature. A road coded as Unknown is a road, which in the judgment of the photogrammetrist, does not fall into any of the categories listed.

Centerlines will be visually placed between the edges of pavement. One (1) centerline will be placed between each edge of pavement. Roads with medial strips, such as Limited Access Roads, will have two (2) centerlines for those portions of the road where the medial strip is present.

For roads that terminate with a cul-de-sac, the centerline shall continue through the center of the cul-de-sac and stop at the edge of pavement.

All attribute data will remain for all Street Centerlines that are not updated. For Street Centerlines that are new, the only attribute field that will be populated is the FeatureCode and UPDATE_YEAR. If a Street Centerline is graphically modified, the existing attribute data will remain and the UPDATE_YEAR will be set to 2004. The attribute values for 2004 Street Centerlines should be considered suspicious until verified.

The ArcInfo Street Centerline coverage that is being updated has 800 segments of Paper Streets, 66 segments of Vacated Streets and 78 segments of Steps. Street Centerlines that are coded as Paper Streets in the OWNER field will remain unchanged in the updated dataset unless the area has been developed. In the event the area has been developed, the Street Centerlines will be modified to reflect the true condition of the visible roads. Street Centerlines that are coded as Vacated in the OWNER field will also remain unchanged in the updated dataset. In the event the area coinciding with the Vacated Streets has been developed, the Vacated Street Centerlines will be removed in order to reflect the true condition of the area.

Street Centerlines that are coded as Steps in the OWNER field will be updated to reflect the current condition of the area.

The Street Centerlines dataset consists of an external table that links to the supplied coverages and the Geodatabase created for this project using the "<coverage>-ID" (UserID) field. In order to maintain the link to the external table and not loose valuable data the decision was made to keep all database information currently in the Street Centerline dataset. When a Street Centerline is modified during the update process, the field "UPDATE_YEAR" is set to 2004. All other database attributes will remain unchanged from the original values. All Street Centerline database data with an "UPDATE_YEAR" of 2004 should be verified before used. In some occasions the Street Centerline was divided into two (2) sections to allow for a new road intersection. Both sections of the resulting Street Centerline will have the same database attributes including Address Range. All new Street Centerlines will have zero (0) for "SystemID" and "UserID".

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:
The original mapping (1992-1993) was created using Pennsylvania State Plane South Zone 3702; North American Horizontal Datum (NAD) 1983; North American Vertical Datum (NGVD) 1929. As part of the GIS update the horizontal coordinate system has been adjusted to NAD 1983 High Accuracy Reference Network (HARN) 1992 Adjustment and National Geodetic Vertical Datum (NGVD) 1988. ESRI does not have routines available for the horizontal HARN adjustment or the vertical adjustment. To accomplish the adjustment of the existing map data an average horizontal and vertical shift was determined. The average shift was then applied to all map data prior to updating.

The datum shift involved moving the map data a set distance. The distance the map data was moved: " X=0.611' " Y=-0.358' " Z=-0.5'

Note: The available coordinate system definitions in ArcGIS 8.3 do not include HARN for Pennsylvania. The horizontal coordinate system defined in the delivered ArcGIS 8.3 Personal Geodatabase is set to NAD83. This will need to be redefined once ESRI incorporates HARN for Pennsylvania.

Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: Spring 2004
Currentness_Reference: publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: As needed
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -80.373729
East_Bounding_Coordinate: -79.670487
North_Bounding_Coordinate: 40.691391
South_Bounding_Coordinate: 40.180389
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Categories
Theme_Keyword: transportation
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: 412 350-4774
Contact_Facsimile_Telephone: 412 350-4754
Native_Data_Set_Environment:
Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.1.0.780
Cross_Reference:
Citation_Information:
Originator:
Allegheny County Division of Computer Services Geographic Information Systems Group

Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
Data was subject to visual check by County GIS Staff for attribute accuracy.

NOTE: This data is considered to be spatially accurate, but lacking attributes such as address ranges, street names and zip codes, making it inappropriate for geocoding applications.

Logical_Consistency_Report:
Data was subject to QA/QC process by county GIS Staff at the time it was recieved - 1992-1996 and 2004 - 2005. The "<coverage>#" and "<coverage>-ID" items from the 1993 and 1994 ArcInfo coverages have been transferred to the geodatabase for all map features that have not been modified. The purpose of the retention of this data is to allow linking of the geodatabase to the original coverages. The values from the ArcInfo coverage item "<coverage>#" are loaded into the geodatabase field "SystemID". The values from the ArcInfo coverage item "<coverage>-ID" are loaded into the geodatabase field "UserID". All map features that have been modified or added during the 2004 update, with the exception of Street Centerlines, will have the value for "SystemID" and "UserID" set to zero (0).
Completeness_Report:
As part of the 2004 update project, mapping was provided covering an area extending 1500 feet beyond the county boundary line. All planimetric, contour and DTM features were delivered in ESRI geodatabase format as County-wide seamless Feature Classes.

NOTE: This data is considered to be spatially accurate, but lacking attributes such as address ranges, street names and zip codes, making it inappropriate for geocoding applications.

Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
All horizontal control is to NGS Second Order Class I accuracy or better and photo control points are reported on the North American Datum (NAD) 1983 U.S. Survey Feet. The aerial photography was captured at a negative scale of 1" = 1,600' and is sufficient to produce mapping at 1" = 200' that conforms to National Mapping Accuracy Standards (NMAS).
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: +/- 5 feet
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
All final elevations are referenced to North American Vertical Datum (NAVD) 1988. Orthometric heights utilize GEOID 99. The network adheres to the Federal Geodetic Control Committee Standards (FGCS) guidelines and the final constrained adjustments were made with StarNet Least Squares Adjustment program and are acceptable by the National Geodetic Survey (NGS).
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: Spring 1992
Ending_Date: Spring 1993
Source_Currentness_Reference: flight time
Source_Citation_Abbreviation: Baymont Tiles
Source_Contribution:
In the spring of 1992, Baymont Technologies entered into 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 Michael 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.
Source_Information:
Source_Citation:
Citation_Information:
Originator: Allegheny County
Publication_Date: 2005
Title: 2004 Flyover
Source_Scale_Denominator: 200'
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: Spring 2004
Source_Currentness_Reference: flight date
Source_Citation_Abbreviation: 2004 Flyover
Source_Contribution:
Digital Globe and Michael Baker Corporation held a contract with Allegheny County to fly the County to produce digital orthophotography and to update planimetric base data for Allegheny County. Subcontractors for the project included: T3 Global Strategies, Sweet Solutions and Keystone Aerial Surveys.
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
Source_Produced_Citation_Abbreviation: County GIS Staff
Process_Step:
Process_Description:
ArcInfo coverages were created from MicroStation design files using in-house developed translation software. Allegheny County's Data Dictionary was used as the base upon which the ArcInfo structure was designed. Each coverage was subjected to review and inspection using ArcMap. Any revisions or corrections were performed in the MicroStation design files. After any corrections were performed, the files were re-translated, re-plotted and re-checked to confirm correct translations. ArcMap was then used to visually check the planimetric data against the digital orthophoto on a tile basis. The final QC step was to merge all tiles to verify the edgematch. Validation was done using MRF. The ESRI tool LOADDATA was used to convert coverages to the final deliverable format, the geodatabase.
Source_Used_Citation_Abbreviation: 2004 Flyover
Process_Date: Spring 2004
Source_Produced_Citation_Abbreviation: Michael Baker Engineers
Process_Step:
Process_Description: Data was loaded into ArcSDE
Process_Time: 2005-2006
Source_Produced_Citation_Abbreviation: County GIS Staff
Process_Step:
Process_Description: Metadata was created.
Process_Time: Summer 2006
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: W:\gisstaff\Data_Clip\Shapefiles_for_Clip\streetcl.shp.xml
Process_Step:
Process_Description: Metadata imported.
Source_Used_Citation_Abbreviation: C:\DOCUME~1\t094246\LOCALS~1\Temp\xml2A.tmp

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: String
Point_and_Vector_Object_Count: 116162
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
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Resolution: 1.000000
Altitude_Encoding_Method:
Explicit elevation coordinate included with horizontal coordinates

Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: streetcl
Attribute:
Attribute_Label: Shape
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: MODIFIEDON
Attribute:
Attribute_Label: USERID
Attribute:
Attribute_Label: PREFIX
Attribute:
Attribute_Label: NAME
Attribute:
Attribute_Label: TYPE
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: P
Enumerated_Domain_Value_Definition: Primary Road
Enumerated_Domain:
Enumerated_Domain_Value: S
Enumerated_Domain_Value_Definition: Secondary Road
Attribute:
Attribute_Label: SUFFIX
Attribute:
Attribute_Label: STREETNAME
Attribute_Domain_Values:
Codeset_Domain:
Codeset_Name:
Name of the street or road, where not available, labeled with three asterisks (***)
Codeset_Source:
TIGER files provided to the vendor by County during the 1992-1993 project
Attribute:
Attribute_Label: LLEFT
Attribute:
Attribute_Label: HLEFT
Attribute:
Attribute_Label: LRGT
Attribute:
Attribute_Label: HRGT
Attribute:
Attribute_Label: FROMSTREET
Attribute:
Attribute_Label: TOSTREET
Attribute:
Attribute_Label: ZIPL
Attribute:
Attribute_Label: ZIPR
Attribute:
Attribute_Label: MCDL
Attribute:
Attribute_Label: MCDR
Attribute:
Attribute_Label: OWNER
Attribute:
Attribute_Label: BELTWAY
Attribute:
Attribute_Label: MAJORRD
Attribute:
Attribute_Label: NO_LANES
Attribute:
Attribute_Label: CFCC
Attribute:
Attribute_Label: GDTLINK
Attribute:
Attribute_Label: MODIFIEDBY
Attribute:
Attribute_Label: SHAPE
Attribute_Definition: Feature geometry.
Attribute_Definition_Source: ESRI
Attribute_Domain_Values:
Unrepresentable_Domain: Coordinates defining the features.
Attribute:
Attribute_Label: CREATEDBY
Attribute:
Attribute_Label: CREATEDON
Attribute:
Attribute_Label: ONEWAY
Attribute:
Attribute_Label: UNIQUE_ID
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: SYSTEMID
Attribute:
Attribute_Label: ROUTE_NO
Attribute:
Attribute_Label: ALTERNATEN
Attribute:
Attribute_Label: FEATURECOD
Attribute:
Attribute_Label: UPDATE_YEA
Attribute:
Attribute_Label: SHAPE_len

Distribution_Information:
Distributor:
Contact_Information:
Contact_Person_Primary:
Contact_Person: James M. Frank
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
Contact_Electronic_Mail_Address: jfrank@county.allegheny.pa.us
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: 20080104
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Allegheny County Division of Computer Services Geographic Information Systems Group
Contact_Person: REQUIRED: The person responsible for the metadata information.
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: 412 350-5126
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 Fri Jan 04 12:39:18 2008