Steep Slope Areas of Loudoun County, VA

Data format: SDE Feature Class

File or table name: GISDBB.GISBROW.STEEP_SLOPE_POLY

Coordinate system: Lambert Conformal Conic

Theme keywords: environment, geoscientificInformation, planningCadastre, steep slope, topography, NRCS, slope classification
Abstract: The Steep Slope layer identifies areas with a slope greater than 15% in Loudoun County.

FGDC and ESRI Metadata:
Metadata elements shown with blue text are defined in the Federal Geographic Data Committee's (FGDC) Content Standard for Digital Geospatial Metadata (CSDGM). Elements shown with green text are defined in the ESRI Profile of the CSDGM. Elements shown with a green asterisk (*) will be automatically updated by ArcCatalog. ArcCatalog adds hints indicating which FGDC elements are mandatory; these are shown with gray text.
Identification Information:


Citation:
Citation information:
Originators: Loudoun County, Virginia, Office of Mapping and Geographic Information (OMAGI)


Title:
Steep Slope Areas of Loudoun County, VA
*File or table name: GISDBB.GISBROW.STEEP_SLOPE_POLY


Publication date: 05Feb09
*Geospatial data presentation form: vector digital data


Publication information:
Publication place: Leesburg, VA
Publisher: Loudoun County, VA

Online linkage: see distribution information


Description:
Abstract:
The Steep Slope layer identifies areas with a slope greater than 15% in Loudoun County.

Purpose:
Steep Slope assists in identifying steep slope areas.  Improper uses and disturbances in steep slope areas cause erosion, result in structural failure of structures and roads, and lead to downstream flooding and other hazards.

Supplemental information:
Data are stored in the corporate ArcSDE Geodatabase as a polygon feature class.  The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN (vertical datum, if applicable, NAVD88 HARN), US Survey foot units.

*Language of dataset: en


Time period of content:
Time period information:
Multiple dates/times:
Single date/time:
Calendar date: 2002 in Western Loudoun County
Single date/time:
Calendar date: 2004 in Eastern Loudoun County

Currentness reference:
ground condition

Status:
Progress: Complete
Maintenance and update frequency: As needed. The steep slopes data are derived from the County's Base Map topography data with a 5' contour interval. Determinations regarding steep slopes are to be made during the Location Clearance process.

Spatial domain:
Bounding coordinates:
*West bounding coordinate: -77.963608
*East bounding coordinate: -77.323638
*North bounding coordinate: 39.326259
*South bounding coordinate: 38.845512

Local bounding coordinates:
*Left bounding coordinate: 11635676.520000
*Right bounding coordinate: 11815726.520000
*Top bounding coordinate: 7166517.000000
*Bottom bounding coordinate: 6993087.000000

Keywords:
Theme:
Theme keywords: environment, geoscientificInformation, planningCadastre
Theme keyword thesaurus: ESRI ArcIMS Topic Categories

Theme:
Theme keywords: steep slope, topography, NRCS, slope classification
Theme keyword thesaurus: none

Place:
Place keywords: Virginia, Loudoun, County
Place keyword thesaurus: none

Access constraints: none
Use constraints:
The steep slopes were derived through a modeling process based on topography.  Currently no national standard for this type of process exists.  The steep slopes were generated using the best available data for Loudoun County and should only be used as a reference. 
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data.  These data are provided without warranty of any kind, expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service.  Reliance on these data is at the risk of the user.
These data were generated for use by Loudoun County and are available to the public.  These data are intended for use at 1:2400 scale or smaller.  Acknowledgement of Loudoun County would be appreciated in products derived from this data.

Point of contact:
Contact information:
Contact organization primary:
Contact organization: Loudoun County, VA, Department of Building and Development
Contact position: GIS Administration


Contact address:
Address type: mailing and physical address
Address:
1 Harrison Street SE, 2nd floor
Address:
MS 60
City: Leesburg
State or province: VA
Postal code: 20175
Country: USA

Contact voice telephone: (703)777-0397
Contact facsimile telephone: (703)771-5522


Contact electronic mail address: bad@loudoun.gov


Hours of service: 8:00-5:00 EST, M-F



Security information:
Security classification: Public Information

*Native dataset format: SDE Feature Class
*Native data set environment:
Microsoft Windows Vista Version 6.0 (Build 6002) Service Pack 2; ESRI ArcCatalog 9.3.1.4000


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Data Quality Information:


Attribute accuracy:
Logical consistency report:
Topologically clean

Completeness report:
Features may have been eliminated or generalized due to scale and intended use. To assist Loudoun County, Virginia in the maintenance of the data, please provide any information concerning discovered errors, omissions, or other discrepancies found in the data.

Positional accuracy:
Horizontal positional accuracy:
Lineage:
Source information:
Source citation:
Citation information:
Originators: Loudoun County, OMAGI


Publication date: 2005
Geospatial data presentation form: vector digital data


Type of source media: Topography Feature Class
Source contribution:
Zoning Ordinance requiring steep slopes to be derived from topography.

Process step:
Process description:
The Steep Slope layer is developed from Loudoun County's topography feature class.  A Digital Elevation Model (DEM) with a 10' cell size grid was derived from topography.  The DEM was converted to a slope layer, which contained a slope value within each cell.  Slope values were then rounded up to the next integer value.  The slope raster was then broken into two categories, 15-25% and 25%+.  The steep slope areas less then 5000 sq ft that were not within 25 feet of steep slope areas greater then 5000 sqft. were eliminated unless the combined areas of steep slope polygons within 25 feet of each other totaled 5000 sq ft or greater.

Process date: November 2006


Process contact:
Contact information:
Contact organization primary:
Contact organization: Loudoun VA, OMAGI
Contact position: GIS Analyst


Process step:
Process description:
This feature class was loaded into the Loudoun County corporate ARCSDE Geodatabase as a polygon feature class.

Process date: December 2006


Process contact:
Contact information:
Contact organization primary:
Contact organization: Loudoun County, VA, Department of Building & Development
Contact position: GIS Admistration


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Spatial Data Organization Information:


Indirect spatial reference method:
Loudoun County


*Direct spatial reference method: Vector


Point and vector object information:
SDTS terms description:
*Name: GISDBB.GISBROW.STEEP_SLOPE_POLY
*SDTS point and vector object type: G-polygon
*Point and vector object count: 42373

SDTS terms description:
SDTS point and vector object type: Label point
Point and vector object count: 161

SDTS terms description:
SDTS point and vector object type: GT-polygon composed of chains
Point and vector object count: 161

SDTS terms description:
SDTS point and vector object type: Point
Point and vector object count: 812

SDTS terms description:
SDTS point and vector object type: Label point
Point and vector object count: 0

ESRI terms description:
*Name: GISDBB.GISBROW.STEEP_SLOPE_POLY
*ESRI feature type: Simple
*ESRI feature geometry: Polygon
*ESRI topology: FALSE
*ESRI feature count: 42373
*Spatial index: TRUE
*Linear referencing: FALSE


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Spatial Reference Information:


Horizontal coordinate system definition:
Coordinate system name:
*Projected coordinate system name: NAD_1983_HARN_StatePlane_Virginia_North_FIPS_4501_Feet
*Geographic coordinate system name: GCS_North_American_1983_HARN

Planar:
Map projection:
*Map projection name: Lambert Conformal Conic
Lambert conformal conic:
*Standard parallel: 38.033333
*Standard parallel: 39.200000
*Longitude of central meridian: -78.500000
*Latitude of projection origin: 37.666667
*False easting: 11482916.666667
*False northing: 6561666.666667

Planar coordinate information:
*Planar coordinate encoding method: coordinate pair
Coordinate representation:
*Abscissa resolution: 0.000208
*Ordinate resolution: 0.000208
*Planar distance units: survey feet

Geodetic model:
*Horizontal datum name: D_North_American_1983_HARN
*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 datum name: Not Applicable
*Altitude resolution: 0.250000
Altitude distance units: Not Applicable
Altitude encoding method: Explicit elevation coordinates do not apply to this layer

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Entity and Attribute Information:


Detailed description:
*Name: GISDBB.GISBROW.STEEP_SLOPE_POLY


Entity type:
*Entity type label: GISDBB.GISBROW.STEEP_SLOPE_POLY
*Entity type type: Feature Class
*Entity type count: 42373
Entity type definition:
Polygon Feature Class
Entity type definition source:
ESRI

Attribute:
Attribute label: OBJECTID
*Attribute alias: OBJECTID
Attribute definition:
Internal feature number.
Attribute definition source:
ESRI

*Attribute type: OID
*Attribute width: 4
*Attribute precision: 10
*Attribute scale: 0


Attribute domain values:
Unrepresentable domain:
Sequential unique whole numbers that are automatically generated.


Attribute:
Attribute label: ST_TYPE
*Attribute alias: ST_TYPE
Attribute definition:
Slope category of steep slope area
Attribute definition source:
Loudoun County

*Attribute type: String
*Attribute width: 50
*Attribute precision: 0
*Attribute scale: 0


Attribute domain values:
Enumerated domain:
Enumerated domain value: Moderate
Enumerated domain value definition:
15-25% slope

Enumerated domain:
Enumerated domain value: Very
Enumerated domain value definition:
25% and greater

Attribute:
Attribute label: SO_SLOPE
*Attribute alias: SO_SLOPE
Attribute definition:
Temporary attribute field.  To work with Loudoun County Land Managment Information System (LMIS)
Attribute definition source:
Loudoun County

*Attribute type: String
*Attribute width: 1
*Attribute precision: 0
*Attribute scale: 0


Attribute:
Attribute label: ST_UPD_SOURCE
*Attribute alias: ST_UPD_SOURCE
Attribute definition:
Source that created or modified feature class
Attribute definition source:
Loudoun County

*Attribute type: SmallInteger
*Attribute width: 2
*Attribute precision: 5
*Attribute scale: 0


Attribute domain values:
Enumerated domain:
Enumerated domain value: See Overview Description for data dictionary of attribute

Attribute:
Attribute label: ST_UPD_DATE
*Attribute alias: ST_UPD_DATE
Attribute definition:
Date feature class created or modified
Attribute definition source:
Loudoun County

*Attribute type: Date
*Attribute width: 36
*Attribute precision: 0
*Attribute scale: 0


Attribute domain values:
Codeset Ddomain:
Codeset name: User defined text

Attribute:
Attribute label: ST_UPD_USER
*Attribute alias: ST_UPD_USER
Attribute definition:
Not for public distribution.  Internal User ID of editor creating or modifying feature class.
Attribute definition source:
Loudoun County

*Attribute type: SmallInteger
*Attribute width: 2
*Attribute precision: 5
*Attribute scale: 0


Attribute:
Attribute label: SHAPE
*Attribute alias: SHAPE
Attribute definition:
Feature geometry.
Attribute definition source:
ESRI

*Attribute type: Geometry
*Attribute width: 4
*Attribute precision: 0
*Attribute scale: 0


Attribute domain values:
Unrepresentable domain:
Coordinates defining the features.


Attribute:
*Attribute label: DB2GSE.ST_Area(SHAPE)
*Attribute alias: DB2GSE.ST_Area(SHAPE)
Attribute definition:
SDE area of steep slope area
Attribute definition source:
Loudoun County

*Attribute type: Double
*Attribute width: 0
*Attribute precision: 0
*Attribute scale: 0


Attribute domain values:
Unrepresentable domain:
Positive whole numbers that are automatically generated.


Attribute:
*Attribute label: DB2GSE.SdeLength(SHAPE)
*Attribute alias: DB2GSE.SdeLength(SHAPE)
Attribute definition:
SDE perimeter of steep slope area
Attribute definition source:
Loudoun County

*Attribute type: Double
*Attribute width: 0
*Attribute precision: 0
*Attribute scale: 0


Attribute domain values:
Unrepresentable domain:
Positive whole numbers that are automatically generated.


Overview description:
Entity and attribute overview:
ST_UPD_SOURCE: Source that created or modified feature class

Entity and attribute detail citation:
Source    Definition

0              Undetermined
10            Legacy 
20            County
30            Contract
40            Model

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Distribution Information:


Distributor:
Contact information:
Contact organization primary:
Contact organization: Loudoun County, VA, OMAGI
Contact position: Public Information Counter


Contact address:
Address type: mailing and physical address
Address:
1 Harrison Street S.E., 2nd floor
Address:
MS 65
City: Leesburg
State or province: VA
Postal code: 20175
Country: USA

Contact voice telephone: (703)771-5778
Contact facsimile telephone: (703)771-5075


Contact electronic mail address: mapping@loudoun.gov


Hours of service: 8:00-4:30 EST, M-F



Resource description: Offline data


Distribution liability:
Every reasonable effort has been made to assure the accuracy of these data. Loudoun County, Virginia does not assume any liability arising from the use of these data.  These data are provided without warranty of any kind, expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular service.  Reliance on these data is at the risk of the user.

Standard order process:
Digital form:
Digital transfer information:
Format name: GDB
Format specification:
ESRI Personal Geodatabase Feature Class

Digital transfer option:
Offline option:
Offline media: DVD

Digital form:
Digital transfer information:
Format name: SHP
Format specification:
ESRI Shapefile

Digital transfer option:
Offline option:
Offline media: DVD

Digital form:
Digital transfer information:
Format name: DXF
Format specification:
AutoCad Digital Exchange File

Digital transfer option:
Offline option:
Offline media: DVD

Fees: Loudoun County distributes spatial data in ArcGIS database or shapefile & DXF format for the cost of reproduction. Countywide spatial datasets may be purchased for $22 per DVD for up to 4.5 GB of data. There is a $100 surcharge to purchase countywide topography, and a $3 charge if the item is to be mailed. If the customer wants the data in DXF format and/or would like OMAGI to custom select specific geographic areas of the County, there is an additional $7 per 15 minute increment labor charge. Select aerial imagery is also available.
Ordering instructions:
Size limit: 4.5 GB. Visit our website at: http://www.loudoun.gov/omagi, click on "Loudoun County Mapping Documents & Order Forms."  The "Forms" directory will lead you to custom & standard (countywide) data order forms.

Hardcopy maps may also be available; please contact the Mapping Office Public Information Counter for more information regarding all data requests.


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Metadata Reference Information:


*Metadata date: 20111021


*Language of metadata: en


Metadata contact:
Contact information:
Contact organization primary:
Contact organization: Loudoun County, VA, OMAGI
Contact position: Metadata Specialist


Contact address:
Address type: mailing and physical address
Address:
1 Harrison Street SE, 2nd Floor
Address:
MS 65
City: Leesburg
State or province: VA
Postal code: 20175
Country: USA

Contact voice telephone: (703)771-5778
Contact facsimile telephone: (703)771-5075


Contact electronic mail address: mapping@loudoun.gov


Hours of service: 8:00-4:30 EST, M-F



*Metadata standard name: FGDC Content Standards for Digital Geospatial Metadata
*Metadata standard version: FGDC-STD-001-1998
*Metadata time convention: local time


Metadata use constraints:
This metadata reflects the source Geodatabase format and specific elements may not apply if your data is exported to SHP or DXF products. User must be aware that changes to data schema occur during data export that may not be reflected in this metadata, which represents Loudoun County's corporate geodatabase. Acknowledgement of Loudoun County would be appreciated in the use of this metadata.


Metadata extensions:
*Online linkage: http://www.esri.com/metadata/esriprof80.html
*Profile name: ESRI Metadata Profile

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