| Soil Mapping Units (lines) of Loudoun County, VA (2010) | |
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Data format: SDE Feature Class File or table name: GISDBB.GISBROW.SOILS_LINE Coordinate system: Lambert Conformal Conic Theme keywords: geoscientificInformation, soil, soil series, soil association, geology, land use, slope, mapping unit potential, rock, bedrock, wetness, plastic, limestone, karst, floodplain |
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Abstract:
The general soil association map outlines broad areas which have distinctive patterns in landscape and general geographic appearance. Each of the soil associations has a unique set of features which effect general use and management including shape and length of slope; width of ridgetops and valleys; frequency, size, and direction of streams; type of vegetation, rate of growth; and agriculture. These differences are largely the result of broad differences in kinds of soils and in the geologic materials from which the soils formed. A mapping unit typically consists of one or more major soils with minor soils, and is named for the major soils.
This map shows, in small scale, a summary of the information contained on the individual detailed soil maps for Loudoun County. Because of its small scale and general soil descriptions, it is not suitable for planning small areas or specific sites, but it does present a general picture of soils in the County, and can show large areas generally suited to a particular kind of agriculture or other special land use. For more detailed and specific soils information, please refer to the detailed soils maps and other information available from the County Soil Scientist.
Digital data consists of mapping units of the various soil types found in Loudoun County, Virginia. The data were collected by digitizing manuscript maps derived from USDA soil maps and supplemented by both field work and geological data.
Field work for the soil survey was first conducted between 1947 and 1952. Soils were originally shown at the scale of 1:15840 and then redrafted by the County soil scientist to 1:12000; the data were redrafted a final time to fit Loudoun County's base map standard of 1:2400.
Although the current data rely heavily on the original soil survey, there have been extensive field checks and alterations to the soil map based on current soil concepts and land use. The data are updated as field site inspections or interpretation changes occur. |
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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.
The general soil association map outlines broad areas which have distinctive patterns in landscape and general geographic appearance. Each of the soil associations has a unique set of features which effect general use and management including shape and length of slope; width of ridgetops and valleys; frequency, size, and direction of streams; type of vegetation, rate of growth; and agriculture. These differences are largely the result of broad differences in kinds of soils and in the geologic materials from which the soils formed. A mapping unit typically consists of one or more major soils with minor soils, and is named for the major soils.
This map shows, in small scale, a summary of the information contained on the individual detailed soil maps for Loudoun County. Because of its small scale and general soil descriptions, it is not suitable for planning small areas or specific sites, but it does present a general picture of soils in the County, and can show large areas generally suited to a particular kind of agriculture or other special land use. For more detailed and specific soils information, please refer to the detailed soils maps and other information available from the County Soil Scientist.
Digital data consists of mapping units of the various soil types found in Loudoun County, Virginia. The data were collected by digitizing manuscript maps derived from USDA soil maps and supplemented by both field work and geological data.
Field work for the soil survey was first conducted between 1947 and 1952. Soils were originally shown at the scale of 1:15840 and then redrafted by the County soil scientist to 1:12000; the data were redrafted a final time to fit Loudoun County's base map standard of 1:2400.
Although the current data rely heavily on the original soil survey, there have been extensive field checks and alterations to the soil map based on current soil concepts and land use. The data are updated as field site inspections or interpretation changes occur.
Digital data are used to identify the mapping unit potential for a variety of uses, such as agriculture drainfield suitability, construction concerns, or development possibility.
This material is intended for planning purposes, as well as to alert the reader to the broad range of conditions, problems, and use potential for each mapping unit.
The mapping unit potential use rating refers to the overall combination of soil properties and landscape conditions. The information in this data set will enable the user to determine the distribution and extent of various classes of soil and generally, the types of problems which may be anticipated.
HOW NOT TO USE THIS INFORMATION
The information in this guide is NOT intended for use in determining specific use or suitability of soils for a particular site. It is of utmost importance that the reader understand that the information is geared to mapping unit potential and not to specific site suitability. An intensive on-site evaluation should be made to verify the soils map and determine the soil/site suitability for the specific use of a parcel.
The original Soil Survey was written for agricultural purposes, but the emphasis has shifted to include urban/suburban uses. The Revised Soil Survey is currently under technical review and is expected to be published by 2006.
The Interpretive Guide to the Use of Soils Maps; Loudoun County, VA, is available at the Public Information Counter for the Office of Mapping and Geographic Information. It contains more detailed soils information.
Data are stored in the corporate ArcSDE Geodatabase as a line feature class. The coordinate system is Virginia State Plane (North), Zone 4501, datum NAD83 HARN.
publication date
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. 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.
1 Harrison St. SE, 2nd Floor
MS 60
Retention of attribute accuracy throughout the coverage to geodatabase feature class conversion process was ensured by a QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have, on a record by record basis, identical attribution when comparing all concatenated fields to all the user-defined attribution.
Topologically Clean
The soils map is continuously being updated based on field site inspections and therefore the soils map merely represents a point in time. 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.
Retention of coordinate accuracy throughout the coverage to geodatabase feature class conversion process was ensured by a QA/QC programmatic check. To meet satisfactory QA/QC requirements the input coverage and output feature class must have the same record total, and on a record by record basis, area, perimeter and length differential of less than +/- 0.5%.
originated soil mapping units and concepts for agricultural uses in Louodun County
revised soil survey for Loudoun County to emphasize general uses
The Soil Survey of Loudoun County (field work) was conducted between 1947 and 1952 by soil scientists from Virginia Tech and the USDA Soil Conservation Service. Soils were originally shown on 1938 aerial photography at a scale of 4"= -1 mile; soils were later redrafted to a scale of 1" = 1666' (1:20000) for publication in the USDA's Soil Survey of Loudoun County, Virginia, Series 1951, Number 8, which was issued in September 1960. This publication is out of print, and the supply of copies for public distribution has been exhausted. A revision of the soil survey for Loudoun County has been completed. The manuscript is currently undergoing technical review and publication of the final document is anticipated during the 2006 calendar year.
As part of the County's Geographic Information System (G.I.S.) mapping project, the soil survey maps were redrafted onto the County's base maps, at a scale of 1" = 200', then digitized. This information is available at the Office of Mapping and Geographic Information or through the County soil scientist in the Cooperative Extension Office . Although these updated soil maps rely heavily on the original soil survey, changes in both location of mapping unit lines and mapping unit descriptions/interpretations have occurred.
The soils map is continuously being updated based on field site inspections and therefore the soils map merely represents a point in time. Many new soil series concepts have been developed and the emphasis has changed from primarily agricultural use to include urban uses. This report is geared to mapping unit potential for general uses. Mapping unit potential ratings attempt to describe the broad range of conditions found in any given mapping unit for the noted uses. For more site-specific soil interpretations contact the County Soil Scientist in the Department of Building and Development.
This data set was part of a batch process that converted legacy data from ArcInfo coverage in Librarian to a single-tiled ArcInfo coverage in preparation for a final conversion to ArcSDE Geodatabase Feature Classes. Data were extracted from Librarian using the EXTRACT TOPOLOGICAL command.
Multi-tiled data sets were extracted into multiple coverages and then combined based on the feature type(s). Layers with both polygon and arc feature classes were processed with the Arc commands MAPJOIN and DISSOLVE. Arc feature classes alone were processed with the Arc commands, APPEND and DISSOLVE. Layers with both arc and point feature classes and point feature classes alone were processed with the Arc command, APPEND. When used, the arc command, DISSOLVE, was given with the <#all> option.
All coverages were then reprojected to HARN83 using the following .prj file specifications:
INPUT
PROJECTION STATEPLANE
UNITS FEET
ZONE 5551
DATUM NAD27 NADCON
PARAMETERS
OUTPUT
PROJECTION STATEPLANE
UNITS FEET
FIPSZONE 4501
DATUM HPGN NADCON
PARAMETERS END
The dataset was then converted to a feature class in a geodatabase in ArcSDE.
Soils_Line feature class converted from the soils arc coverage to generate new feature class. The unnecessary coverage-related attribute fields, FNODE#, TNODE#, LPOLY#, RPOLY#, SOILS#, & SOIL_ID, were removed from the feature class.
Not for public distribution. Internal User ID of editor creating or modifying a feature.
Loudoun County
Internal feature number.
ESRI
Feature geometry.
ESRI
Unique code to identify type of soil line
Loudoun County
Source that created or modified feature class
Loudoun County
Date feature class created or modified
Loudoun County
SO_SOIL: Unique code to identify type of soil line
Code Description 0 To be removed & replaced with 99 or correct code when determined 1 Soil lines 2 Double stream lines (larger streams) 3 Ponds 4 County boundary 7 Dry pond edge 8 Graded areas 99 Undetermined or under review
SO_UPD_SOURCE: Source that created or modified feature class
Source Description 0 Unknown 1 Legacy 2 County 3 Contract
1 Harrison Street, S.E., 2nd Floor
MS 65
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.
ESRI Geodatabase Feature Class
ESRI Shapefile
AutoCad Digital Exchange File
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.
1 Harrison Street S.E., 2nd Floor
MS 65