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Estimated Depth to Water, North Carolina

Open File Report 01-487
By J.L. Eimers, Silvia Terziotti, and Mary Giorgino


Project Description

Metadata · Metadata as Plain Text file

Depth to water

Project Description for Map Data Produced as Part of the North Carolina Source Water Assessment Program


Abstract

This web site contains the Federal Geographic Data Committee-compliant metadata (documentation) for digital data produced for the North Carolina, Department of Environment and Natural Resources, Public Water Supply Section, Source Water Assessment Program. The metadata are for 11 individual Geographic Information System data sets. An overlay and indexing method was used with the data to derive a rating for unsaturated zone and watershed characteristics for use by the State of North Carolina in assessing more than 11,000 public water-supply wells and approximately 245 public surface-water intakes for susceptibility to contamination. For ground-water supplies, the digital data sets used in the assessment included unsaturated zone rating, vertical series hydraulic conductance, land-surface slope, and land cover. For assessment of public surface-water intakes, the data sets included watershed characteristics rating, average annual precipitation, land-surface slope, land cover, and ground-water contribution. Documentation for the land-use data set applies to both the unsaturated zone and watershed characteristics ratings. Documentation for the estimated depth-to-water map used in the calculation of the vertical series hydraulic conductance also is included.


Abstract || Introduction || Purpose || Contents || Links to Metadata || References

Introduction

Overlay and index methods for rating the unsaturated zone and watershed characteristics were derived for use by the State of North Carolina in assessing more than 11,000 public water-supply wells and approximately 245 public surface-water intakes for susceptibility to contamination. Factors that influence the vulnerability of public ground water and surface water supplies to contamination were selected and assigned ratings on a scale of 1 to 10, covering the range of values in North Carolina. These factors then were assigned weight to reflect their relative influence on the perceived inherent vulnerability and reliability of the data (Eimers and others, 2000).

Factors selected for rating the vulnerability to contamination of the unsaturated zone are vertical series hydraulic conductance, land-surface slope, land cover, and land use. Vertical series hydraulic conductance measures the capacity of unsaturated material to transmit water. Land-surface slope influences whether precipitation runs off land surfaces or infiltrates into the subsurface. Land cover describes the physical overlay of the land surface, which influences the amount of precipitation that runs off or infiltrates into the subsurface. Land use describes activities occurring on the land surface that influence the potential generation of nonpoint-source contamination.

In order to develop the unsaturated zone vulnerability rating, an estimated depth-to-water map was created. The estimated depth-to-water map was necessary for the calculation of the vertical series hydraulic conductance values. A documentation file was created describing methods and formulas that were applied to generate this data set.

Factors selected for rating the watershed characteristics upstream from surface-water intakes are average annual precipitation, land-surface slope, land cover, land use, and ground-water contribution. The average annual precipitation represents the amount of water available for transport in a watershed. Land-surface slope, land cover, and land use have similar influences on watershed characteristics as those identified for the unsaturated zone. Ground-water contribution represents the part of streamflow that is derived from ground water.

The values for each factor were obtained from Geographic Information System (GIS) data layers stored as raster data sets. These raster data sets have 30-meter by 30-meter cells, and each cell is assigned a value based on the characteristics of the factor within that cell. Only one data set was created for the land-use factor because identical ratings were applied for the unsaturated zone rating and watershed characteristics rating. The values for each factor were assigned a weight, then the weighted values were combined to create the final vulnerability values for the unsaturated zone and watershed characteristics ratings.

A structured documentation file (known as "metadata") for each data set has been created. The documentation files comply with the Federal Geographic Data Committee (FGDC) Content Standards for Digital Geospatial Metadata (Federal Geographic Data Committee, 1994). The FGDC-compliant metadata files contain descriptions of the data sets and include narrative sections describing the procedures used to produce the data sets in digital form. The metadata also include references of the sources used to create the data set.


Abstract || Introduction || Purpose || Contents || Links to Metadata || References

Purpose

This page provides background context for the 11 digital data sets created for the North Carolina Source Water Assessment Program (SWAP), and is the access point for all associated metadata files.


Abstract || Introduction || Purpose || Contents || Links to Metadata || References

Contents

The FGDC-compliant metadata for the 11 data sets are linked below. The digital data are not currently online because of space limitations. The digital data sets can be requested through the distribution contact identified in the metadata.


Abstract || Introduction || Purpose || Contents || Links to Metadata || References

Links to metadata

Links to jpeg images
of the data sets

Unsaturated Zone Characteristics Rating for North Carolina (OFR 01-489) Inherent vulnerability categories for rating the unsaturated zone
Percent-Slope Classes to Characterize the Unsaturated Zone in North Carolina (OFR 01-495) Percent slope categories for rating the unsaturated zone
Land-Cover Classes to Characterize the Unsaturated Zone in North Carolina (OFR 01-491) Landcover categories for rating the unsaturated zone
Vertical Series Hydraulic Conductance Classes to Characterize the Unsaturated Zone in North Carolina (OFR 01-486) Vertical hydraulic conductance categories for rating the unsaturated zone
Estimated Depth to Water, North Carolina (OFR 01-487) Depth to water
Land-Use Classes to Characterize Watersheds and the Unsaturated Zone in North Carolina (OFR 01-493) Landuse categories for rating the unsaturated zone and watershed characteristics
Watershed Characteristics Rating for North Carolina (OFR 01-490) Inherent vulnerability categories for rating watershed characteristics
Land-Cover Classes to Characterize Watersheds in North Carolina (OFR 01-492) Landcover categories for rating watershed characteristics
Average Annual Precipitation Classes to Characterize Watersheds in North Carolina (OFR 01-494) Average annual precipitation categories
Percent-Slope Classes to Characterize Watersheds in North Carolina (OFR 01-496) Percent slope categories for rating watershed characteristics
Ground-Water Contribution Classes to Characterize Watersheds in North Carolina (OFR 01-488) Ground-water contribution categories

Abstract || Introduction || Purpose || Contents || Links to Metadata || References

References

Eimers, J.L., Weaver, J.C., Terziotti, Silvia, and Midgette, R.W., 2000, Methods of rating unsaturated zone and watershed characteristics of public water supplies in North Carolina: U.S. Geological Survey Water-Resources Investigations Report 99-4283, 31 p.

Federal Geographic Data Committee, 1994, Content standards for digital geospatial metadata (June 8): Washington, D.C., Federal Geographic Data Committee, 78 p.



USGS home page

Estimated Depth to Water, North Carolina

Open File Report 01-487
By J.L. Eimers, Silvia Terziotti, and Mary Giorgino

Metadata

Metadata is also available as a Plain Text file.


Identification_Information:

Citation:
Citation_Information:
Originator: Jo Leslie Eimers
Originator: Silvia Terziotti
Originator: Mary Giorgino
Publication_Date: 2001
Title: Estimated Depth to Water, North Carolina
Edition: Version 1.0, March 06, 2001
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-487
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: U.S. Geological Survey
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01487/index.html

Description:

Abstract:

An estimated depth-to-water map was generated for the State of North Carolina. For the Coastal Plain and Piedmont Provinces, a regression equation was used to estimate the depth to water. A conceptual model was used in conjunction with water-level data to estimate the depth to water in the Blue Ridge Province.

Purpose:

This data set was created as part of the North Carolina Source Water Assessment Program (SWAP). This data is used in the calculation of vertical hydraulic conductance ratings, one of the factors needed to complete the unsaturated zone rating of public water supplies in North Carolina.

Supplemental_Information:

A depth-to-water map was generated for the State of North Carolina. For the Coastal Plain and Piedmont Provinces, a regression equation was developed to estimate depth to water based on water-level records for 872 wells. The explanatory variables are surface elevation, in feet (elev); slope, in percent (slope); and soil thickness, in feet (thickness):

  dtw = -5.3870 + 0.0622*elev + 0.2959*slope + 1.7001*thickness

where dtw is depth to water, in feet below land surface

A conceptual model was used to estimate depth to water in the Blue Ridge Province. The Blue Ridge Province was divided into four categories reflecting topographic settings-- hilltops, slopes greater than 10% where water accumulates, slopes greater than 10% where water does not accumulate, and valleys.

Using records for 393 wells, the following median water levels were assigned to topographic settings in the Blue Ridge Province:

      Topographic setting                 Depth to water (feet)
     ------------------------
     Hilltops               H                    36.0
     Slopes without flow    U                    28.0
       accumulation
     Slopes with flow       D                    25.5
       accumulation
     Valleys                V                    15.0

Further information about the methods used to create the depth-to-water map are available in Eimers and others (2001).

Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

Although this Federal Geographic Data Committee-compliant metadata file is intended to document the data set in nonproprietary form as well as in ARC/INFO format, the metadata file may include some ARC/INFO-specific terminology.

Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2001
Currentness_Reference: 1960 - 2000 water levels

Status:
Progress: Complete
Maintenance_and_Update_Frequency: None Planned

Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -84.42217283
East_Bounding_Coordinate: -75.35577664
North_Bounding_Coordinate: 36.5631918
South_Bounding_Coordinate: 33.64180848

Keywords:
Theme:
Theme_Keyword_Thesaurus: none
Theme_Keyword: Depth to water
Theme_Keyword: Water level
Place:
Place_Keyword_Thesaurus: none
Place_Keyword: North Carolina
Place_Keyword: Blue Ridge province
Place_Keyword: Piedmont province
Place_Keyword: Coastal Plain province

Access_Constraints:
none

Use_Constraints:
These data are not to be used for site-specific analysis

Point_of_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Silvia Terziotti
Contact_Organization: U.S. Geological Survey
Contact_Position: Computer Specialist
Contact_Address:
Address_Type: mailing address
Address: 3916 Sunset Ridge Road
City: Raleigh
State_or_Province: NC
Postal_Code: 27607
Country: USA
Contact_Voice_Telephone: (919) 571-4000
Contact_Facsimile_Telephone: (919) 571-4041
Contact_Electronic_Mail_Address: (seterzio@usgs.gov)

Data_Set_Credit:
The authors are grateful to colleagues in the Public Water Supply Section of the Division of Environmental Health, North Carolina Department of Environment and Natural Resources (DENR) for their assistance in this collaborative project. The authors thank Robert Midgette, Protection and Enforcement Branch Head; Elizabeth Morey, Hydrogeologist; Gale Johnson, Hydrogeologist; and Rajpreet Butalia, Geographic Information Systems Specialist.

The authors also thank the USGS report review team for their review of the metadata products: Stephen J. Char, Jason M. Fine, Michael L. Strobel, Douglas A. Harned and Rebecca J. Deckard.

Native_Data_Set_Environment:
Windows_NT, 5.0, Intel
ARC/INFO version 8.0.2

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Watershed Characteristics Rating for North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-490
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01490/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Unsaturated Zone Characteristics Rating for North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-489
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01489/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Land-Use Classes to Characterize Watersheds and the Unsaturated Zone in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-493
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01493/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Land-Cover Classes to Characterize the Unsaturated Zone in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-491
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01491/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Percent-Slope Classes to Characterize the Unsaturated Zone in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-495
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01495/index.html

Cross_Reference:
Citation_Information:
Originator: Jo Leslie Eimers, Silvia Terziotti and Gloria Ferrell
Publication_Date: 2001
Title: Vertical Series Hydraulic Conductance Classes to Characterize the Unsaturated Zone in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-486
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01486/index.html

Cross_Reference:
Citation_Information:
Originator: Jo Leslie Eimers, Silvia Terziotti and Mary Giorgino
Publication_Date: 2001
Title: Estimated Depth to Water, North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-487
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01487/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Land-Cover Classes to Characterize Watersheds in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-492
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01492/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Average Annual Precipitation Classes to Characterize Watersheds in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-494
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01494/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Percent-Slope Classes to Characterize Watersheds in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-496
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01496/index.html

Cross_Reference:
Citation_Information:
Originator: Silvia Terziotti and Jo Leslie Eimers
Publication_Date: 2001
Title: Ground-Water Contribution Classes to Characterize Watersheds in North Carolina
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: USGS Open-File Report
Issue_Identification: USGS OFR 01-488
Publication_Information:
Publication_Place: Raleigh, NC
Publisher: USGS
Online_Linkage: http://nc.water.usgs.gov/reports/ofr01488/index.html


Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The depth to water values were checked against the source water level data. Ranges of depths match values published in related literature on depth to water.

Logical_Consistency_Report:
Not applicable for raster data.

Completeness_Report:
Blue Ridge Province values reflect median depth-to-water values by topographic setting.

Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Visual checks of interpolated values against original source data.

Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: USGS
Publication_Date: 2001
Title: Ground Water Site Inventory Database
Type_of_Source_Media: online
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2001
Source_Currentness_Reference: data ranges from 1950 to present
Source_Citation_Abbreviation: none
Source_Contribution: fields for water level, well depth, topograhic setting, location

Source_Information:
Source_Citation:
Citation_Information:
Originator: Eimers, Jo Leslie
Originator: Giorgino, M. J.
Originator: Terziotti, Silvia
Title: Estimated Depth to Ground Water in North Carolina
Publication_Date: 2001
Series_Information:
Series_Name: Geological Society of America, Abstracts with Programs
Issue_Identification: 50th Annual Meeting, Southeastern Section, April 5-6, 2001, Raleigh, North Carolina, v. 33, no. 2, p. A-62.
Online_Linkage: not currently online
Geospatial_Data_Presentation_Form: none
Type_of_Source_Media: paper
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2001
Source_Currentness_Reference: data ranges from 1960's to present
Source_Citation_Abbreviation: Eimers and others (2001)
Source_Contribution: explanation of depth-to-water estimation

Source_Information:
Source_Citation:
Citation_Information:
Originator: Eimers, Jo Leslie
Originator: Weaver, J. C.
Originator: Terziotti, Silvia
Originator: Midgette, R. W.
Title: Methods of rating unsaturated zone and watershed characteristics of public water supplies in North Carolina
Publication_Date: 2000
Series_Information:
Series_Name: U. S. Geological Survey Water-Resources Investigations
Issue_Identification: WRIR 99-4283
Type_of_Source_Media: paper
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 2000
Source_Currentness_Reference: publication date
Source_Citation_Abbreviation: Eimers and others (2000)
Source_Contribution: methods for applying ratings

Process_Step:
Process_Description:
Data was downloaded from the USGS Ground water site inventory database to reflect water levels within the surficial aquifer of North Carolina
Process_Date: 2000

Process_Step:
Process_Description:
Data was collected from DENR regional offices for Piedmont and Blue Ridge Provinces to supplement water-level data collected by USGS
Process_Date: 2000

Process_Step:
Process_Description:
Well data were digitized, to get accurate locations.
Process_Date: 2000

Process_Step:
Process_Description:
Overlay analysis in GRID was used to assign values to each well for soil thickness, soil permeability, elevation, percent slope, geology, distance to nearest stream and average annual precipitation.
Process_Date: 2000

Process_Step:
Process_Description:
Linear regression was performed on the data, by physiographic province, to identify explanatory variables and derive an equation for estimating depth to water.
Process_Date: 2000

Process_Step:
Process_Description:
The equation derived for the Coastal Plain and Piedmont was applied to the data:
dtw_ft = -5.3870 + (.0622 * h:\ned2\elev_30m) + (.2959 * h:\ned2\slope_30m) + (1.7001 * z:\soils\thk_ftx100 / 100)
Process_Date: 2001

Process_Step:
Process_Description:
Water bodies were assigned a depth-to-water value of 0.
Process_Date: 2001

Process_Step:
Process_Description:
Topographic settings were defined for Blue Ridge province
(note that comments are not permitted in con statements in GRID, they are inserted here to explain the condition definitions):
 
topo_5cat = con ( ~
/***** ridges
ridge_grd ne 0 && h:\ned2\slope_30m gt 10, 2, ~ /* hilltop
ridge_grd ne 0 && h:\ned2\slope_30m le 10, 1, ~ /* flat
/***** flowacc = 0, but not real ridge
blue_toposet == 1 && ridge_grd == 0 && h:\ned2\slope_30m gt 10, 3, ~ /* upslope
blue_toposet == 1 && ridge_grd == 0 && h:\ned2\slope_30m le 10, 4, ~ /* valley
/***** flowacc > 0 < 25 - upland slopes
blue_toposet == 2 && h:\ned2\slope_30m le 10, 4, ~ /* valley
blue_toposet == 2 && h:\ned2\slope_30m gt 10, 3, ~ /* upslope
/***** flowacc > 25 < 200 - lower slopes
blue_toposet == 3 && h:\ned2\slope_30m le 10 , 4, ~ /* valley
blue_toposet == 3 && h:\ned2\slope_30m gt 10 , 5, ~ /* downslope
/***** flowacc > 200
blue_toposet == 4, 4) /* valley
/* move the flats to valleys...
BLUE_TOPO = con (topo_5cat == 1, 4, topo_5cat)
Process_Date: 2001

Process_Step:
Process_Description:
Create the median depth-to-water grid times 100; 0.005 added to ensure proper rounding:
Additem to blue_topo, and calculate item equal to mean depth to water, by topographic setting.
Create a new grid that has the depth to water values in it, calculate values times 100 to create an integer grid.
Merge the lakes to create depths of zero at lakes.
DTW_BLUE = blue_topo.dtw
DTWBLUEFTX100 = int(merge (h:\depth_to_water\cp_pied\lake_grd, (dtw_blue + .005) * 100 )))
Process_Date: 2001

Process_Step:
Process_Description:
Merge the Coastal Plain/Piedmont depth to water map with the Blue Ridge
DTW_STATE = merge( ..\cp_pied\dtw3_ftx100, h:\blue_Ridge_toposet\dtwblueftx100)
Process_Date: 2001

Process_Step:
Process_Description:
First draft of metadata created by seterzio using FGDCMETA.AML ver. 1.33 07/15/99 on ARC/INFO data set
h:\depth_to_water\state\dtw_state
Process_Date: 20010306


Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 10576
Column_Count: 27060


Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Grid_Coordinate_System:
Grid_Coordinate_System_Name: State Plane Coordinate System 1983
State_Plane_Coordinate_System:
SPCS_Zone_Identifier: 4901
Lambert_Conformal_Conic:
Standard_Parallel: 34.333
Standard_Parallel: 36.167
Longitude_of_Central_Meridian: 79.000
Latitude_of_Projection_Origin: 33.750
False_Easting: 2000000
False_Northing: 0.000
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 30.0
Ordinate_Resolution: 30.0
Planar_Distance_Units: Meters
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: GRS1980
Semi-major_Axis: 6378206.4
Denominator_of_Flattening_Ratio: 294.98


Entity_and_Attribute_Information:
Overview_Description:
Entity_and_Attribute_Overview:

Value Attribute Table, DTW_STATE.VAT:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
    1  VALUE                  4    10     B      -
    5  COUNT                  4    10     B      -

VALUE is the rating: valid values are integers -99 to 13562, inclusive Other than -99 (which reflects waterbodies), the values should be divided by 100 to arrive at actual depth to water values. (Range is 0 to 135.62 feet). COUNT is the number of 30-meter by 30-meter cells in the entire data set that have the particular value

Summary Statistics Table, DTW_STATE.STA:

COLUMN   ITEM NAME        WIDTH OUTPUT  TYPE N.DEC  ALTERNATE NAME
    1  MIN                    8    15     F      3
    9  MAX                    8    15     F      3
   17  MEAN                   8    15     F      3
   25  STDV                   8    15     F      3

Min is the minimum value (-99)
Max is the maximum value (13562)
Mean is the average value
STDV is the standard deviation

    MIN             MAX            MEAN            STDV
-99.000       13562.000        1361.931        1056.346
Entity_and_Attribute_Detail_Citation: none


Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Position: Water Webserver Team
Contact_Address:
Address_Type: mailing and physical address
Address: 12201 Sunrise Valley Drive, MS 440
City: Reston
State_or_Province: VA
Postal_Code: 20192
Country: USA
Contact_Voice_Telephone: (800) 426-9000
Contact_Instructions: Contact via email
Contact_Electronic_Mail_Address: h2oteam@usgs.gov

Distribution_Liability:

Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data.

The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of this data, software, or related materials.


Metadata_Reference_Information:
Metadata_Date: 20010209
Metadata_Review_Date: 2001
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: North Carolina District Chief
Contact_Position: District Chief
Contact_Address:
Address_Type: mailing and physical address
Address: 3916 Sunset Ridge Road
City: Raleigh
State_or_Province: NC
Postal_Code: 27607
Country: USA
Contact_Voice_Telephone: (919) 571-4000
Contact_Facsimile_Telephone: (919) 571-4041
Contact_Electronic_Mail_Address: dc_nc@usgs.gov
Metadata_Standard_Name:
FGDC Content Standards for Digital Geospatial Metadata
("CSDGM version 2")
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Access_Constraints: none
Metadata_Use_Constraints: none

Generated by mp version 2.4.33 on Tue Jan 22 10:16:03 2002
USGS GIS Data for Water Resources || North Carolina District
Last update: Wednesday, December 19 2012, 02:07:38 PM
URL: http://nc.water.usgs.gov/reports/ofr01487/index.html
Privacy Statement || Disclaimer || Accessibility
Maintainer: North Carolina Web Development Team