FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION

TITLE: NATIONAL HYDROGRAPHY DATASET - HYDROGRAPHIC WATERBODY FEATURES 1:100K

Geodataset Name:       NHD100WATERBODY_MAY06
Geodataset Type:       SHAPEFILE
Geodataset Feature:    Polygon
Feature Count:         39935
GENERAL DESCRIPTION:
This data set contains regions representing areal NHD hydrographic waterbody features. The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. This layer is at a scale of 1:100,000 (Medium Resolution), the initial scale at which the NHD was developed. The same layer is available at a scale of 1:24,000 (High Resolution). The NHD data was originally created by the USGS and EPA along with other federal, state, and local agencies. The FDEP is the NHD data steward for Florida. This data was originally in geodatabase format. When in shapefile format the data loses the network functionality of the geodatabase. Please contact the FDEP if you need the original geodatabase. Last Updated, May, 2006
DATA SOURCE(S):                    U.S. Geological Survey in cooperation with U.S. Environmental Protection Agency, USDA Forest Service, and Florida Department of Environmental Protection.
SCALE OF ORIGINAL SOURCE MAPS:     100000
GEODATASET EXTENT:                 State of Florida
PUBLICATION DATE: 20060501 TIME PERIOD OF CONTENT: 20060501 DOWNLOAD LINK: http://www.fgdl.org/metadataexplorer/explorer.jsp

FEATURE ATTRIBUTE TABLES:

Datafile Name: NHD100WATERBODY_MAY06.DBF
ITEM NAME WIDTH TYPE
OBJECTID
4 OID
Shape
4 Geometry
ComID
4 Integer
FDate
36 Date
Resolution
4 Integer
GNIS_ID
10 String
GNIS_Name
65 String
AreaSqKm
8 Double
Elevation
8 Double
ReachCode
14 String
FType
4 Integer
FCode
4 Integer
DESC_
125 String
DESCRIPT
30 String
FGDLAQDATE
36 Date
AUTOID
4 Integer
SHAPE.AREA
0 Double
SHAPE.LEN
0 Double

FEATURE ATTRIBUTE TABLES CODES AND VALUES:

Item
Item Description
OBJECTID Internal feature number.

Shape Feature geometry.

ComID Uniquely identifies the occurrence of each feature

FDate Date of last feature modification

Resolution Code for source resolution
1 = Local Resolution

2 = Hight Resolution

3 = Medium Resolution


GNIS_ID Unique identifier assigned by GNIS

GNIS_Name Proper name specific term or expression by which a particular geographic entity is known

AreaSqKm Area of areal features Albers Equal Area

Elevation Elevation of water surfaces where water pools is encoded for a few features

ReachCode Unique identifier composed of two parts. The first eight digits is the subbasin code as defined by FIPS The next six digits are randomly assigned squential numbers that are unique within a Catalog Unit

FType Three digit integer value unique identifier of a feature type

FCode Five-digit integer value comprised of the feature type and combinations of characteristics and values

DESC_ Description field, which holds a character string that contains all characteristics and values associated with a feature code.

DESCRIPT GeoPlan added field based on Feature Type.

FGDLAQDATE Date GeoPlan acquired data from source.

AUTOID Unique ID added by GeoPlan

SHAPE.AREA Area in meters

SHAPE.LEN Perimeter in meters

The National Hydrography Dataset is a comprehensive set of digital spatial data 
that encodes information about naturally occurring and constructed bodies of 
water, paths through which water flows, and related entities.  The information 
encoded about features includes a feature date, classification by type, other 
characteristics, a unique common identifier, the feature length or area, and (rarely) 
elevation of the surface of water pools and a description of the stage of the 
elevation.  For reaches, encoded information includes a reach code.  Names and 
their identifiers in the Geographic Names Information System, are assigned to most
feature types.  The direction of flow is encoded for networked features.  The data 
also contains relations that encode metadata, and information that supports the 
exchange of future updates and improvements to the data.  The names and  
definitions of all feature types, characteristics, and values are in the Standards for 
National Hydrography Dataset:  Reston, Virginia, U.S. Geological Survey, 1999.  
The document is available online through http://mapping.usgs.gov/standards/.
USER NOTES:
Points, nodes, lines, and areas conform to topological rules.  Lines intersect only at
nodes, and all nodes anchor the ends of lines.  Lines do not overshoot or 
undershoot other lines where they are supposed to meet.  There are no duplicate 
lines.  Lines bound areas and lines identify the areas to the left and right of the 
lines.  Gaps and overlaps among areas do not exist.  All areas close.
The completeness of the data reflects the content of the sources, which most 
often are the published USGS topographic quadrangle and/or the USDA Forest 
Service Primary Base Series (PBS) map. The USGS topographic quadrangle is 
usually supplemented by Digital Orthophoto Quadrangles (DOQs). Features found 
on the ground may have been eliminated or generalized on the source map 
because of scale and legibility constraints. In general, streams longer than one 
mile (approximately 1.6 kilometers) were collected. Most streams that flow from a 
lake were collected regardless of their length. Only definite channels were 
collected so not all swamp/marsh features have stream/rivers delineated through 
them. Lake/ponds having an area greater than 6 acres were collected. Note, 
however, that these general rules were applied unevenly among maps during 
compilation. Reaches codes are defined on all features of type stream/river, 
canal/ditch, artificial path, coastline, and connector. Waterbody reach codes are 
defined on all lake/pond and most reservoir features. Names were applied from 
the GNIS database.  Detailed capture conditions are provided for every feature 
type in the Standards for National Hydrography Dataset available online through 
http://mapping.usgs.gov/standards/.
This statement is generally true for the most common sources of NHD data. Other 
sources and methods may have been used to create or update NHD data. In 
some cases, additional information may be found in the NHDMetadata table.
GeoPlan relied on the integrity of the attribute information within
the original data.

The NHD is a national framework for assigning reach addresses to water-related 
entities, such as industrial discharges, drinking water supplies, fish habitat areas, 
wild and scenic rivers. Reach addresses establish the locations of these entities 
relative to one another within the NHD surface water drainage network, much like 
addresses on streets. Once linked to the NHD by their reach addresses, the 
upstream/downstream relationships of these water-related entities--and any 
associated information about them--can be analyzed using software tools ranging 
from spreadsheets to geographic information systems (GIS). GIS can also be used 
to combine NHD-based network analysis with other data layers, such as soils, 
landuse and population, to help understand and display their respective effects 
upon one another. Furthermore, because the NHD provides a nationally 
consistent framework for addressing and analysis, water-related information linked 
to reach addresses by one organization (national, state, local) can be shared with 
other organizations and easily integrated into many different types of applications 
to the benefit of all.

NHD data was originally developed at 1:100,000-scale and exists at that 
scale for the whole country. This high-resolution NHD, generally developed 
at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. 
(Data for Alaska, Puerto Rico and the Virgin Islands was developed at high
resolution, not 1:100,000 scale.) Local resolution NHD is being developed 
where partners and data exist. The NHD contains reach codes for networked 
features, flow direction, names, and centerline representations for areal water 
bodies. Reaches are also defined on water bodies and the approximate shorelines 
of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The 
NHD also incorporates the National Spatial Data Infrastructure framework criteria 
established by the Federal Geographic Data Committee.

Statements of horizontal positional accuracy are based on accuracy statements 
made for U.S. Geological Survey topographic quadrangle maps.  These maps 
were compiled to meet National Map Accuracy Standards.  For horizontal 
accuracy, this standard is met if at least 90 percent of points tested are within 0.02
inch (at map scale) of the true position.  Additional offsets to positions may have 
been introduced where feature density is high to improve the legibility of map 
symbols.  In addition, the digitizing of maps is estimated to contain a horizontal 
positional error of less than or equal to 0.003 inch standard error (at map scale) in 
the two component directions relative to the source maps.  Visual comparison 
between the map graphic (including digital scans of the graphic) and plots or 
digital displays of points, lines, and areas, is used as control to assess the 
positional accuracy of digital data.  Digital map elements along the adjoining edges
of data sets are aligned if they are within a 0.02 inch tolerance (at map scale).  
Features with like dimensionality (for example, features that all are delineated with 
lines), with or without like characteristics, that are within the tolerance are aligned 
by moving the features equally to a common point. Features outside the tolerance 
are not moved; instead, a feature of type connector is added to join the features.

This statement is generally true for the most common sources of NHD data.  Other 
sources and methods may have been used to create or update NHD data.  In 
some cases, additional information may be found in the NHDMetadata table.

Statements of vertical positional accuracy for elevation of water surfaces are 
based on accuracy statements made for U.S. Geological Survey topographic 
quadrangle maps.  These maps were compiled to meet National Map Accuracy 
Standards.  For vertical accuracy, this standard is met if at least 90 percent of 
well-defined points tested are within one-half contour interval of the correct value.
Elevations of water surface printed on the published map meet this standard; the 
contour intervals of the maps vary.  These elevations were transcribed into the 
digital data; the accuracy of this transcription was checked by visual comparison 
between the data and the map.
This statement is generally true for the most common sources of NHD data. Other 
sources and methods may have been used to create or update NHD data.  In 
some cases, additional information may be found in the NHDMetadata table.

NONE

The Florida Geographic Data Library is a collection of Geospatial Data
compiled by the University of Florida GeoPlan Center with support from
the Florida Department of Transportation. GIS data available in FGDL is
collected from various state, federal, and other agencies (data sources)
who are data stewards, producers, or publishers. The data available in
FGDL may not be the most current version of the data offered by the
data source. University of Florida GeoPlan Center makes no guarantees
about the currentness of the data and suggests that data users check
with the data source to see if more recent versions of the data exist.

Furthermore, the GIS data available in the FGDL are provided 'as is'.
The University of Florida GeoPlan Center makes no warranties, guaranties
or representations as to the truth, accuracy or completeness of the data
provided by the data sources. The University of Florida GeoPlan Center
makes no representations or warranties about the quality or suitability
of the materials, either expressly or implied, including but not limited
to any implied warranties of merchantability, fitness for a particular
purpose, or non-infringement. The University of Florida GeoPlan Center
shall not be liable for any damages suffered as a result of using,
modifying, contributing or distributing the materials.

A note about data scale: 

Scale is an important factor in data usage.  Certain scale datasets
are not suitable for some project, analysis, or modeling purposes.
Please be sure you are using the best available data. 

1:24000 scale datasets are recommended for projects that are at the
county level.
1:24000 data should NOT be used for high accuracy base mapping such
as property parcel boundaries.
1:100000 scale datasets are recommended for projects that are at the
multi-county or regional level.
1:125000 scale datasets are recommended for projects that are at the
regional or state level or larger.

Vector datasets with no defined scale or accuracy should be
considered suspect. Make sure you are familiar with your data
before using it for projects or analysis. Every effort has been
made to supply the user with data documentation. For additional
information, see the References section and the Data Source Contact
section of this documentation. For more information regarding
scale and accuracy, see our webpage at:
http://geoplan.ufl.edu/education.html

REFERENCES:
National Hydrography Dataset:
http://nhd.usgs.gov/

The names and definitions of all feature types, characteristics, and values:
http://mapping.usgs.gov/standards/

Fact Sheet is also available at: 
http://erg.usgs.gov/isb/pubs/factsheets/fs06002.html

DATA LINEAGE SUMMARY:
The processes used to create and maintain high-resolution NHD data can be 
found in the table called "NHDMetadata".  Because NHD data can be 
downloaded using several user-defined areas, the process descriptions can vary 
for each download.  The NHDMetadata table contains a list of all the process 
descriptions that apply to a particular download.   These process descriptions are 
linked using the DuuID to the NHDFeatureToMetadata table which contains the 
com_ids of all the features within the download. In addition, another table, the 
NHDSourceCitation, can also be linked through the DuuID to determine the 
sources used to create or update NHD data.
Process Date: Unknown

Converted NHD data to geodatabase format. Conversion included assignment of FCodes, FDate, and Resolution attribute values; assignment of reach codes to associated features; replacement of branched reaches with linear reaches; merge of area features with identical classification that adjoin or overlap; split of large area features that exceed 100/25 sq. km. (depending on feature type) at subbasin boundaries; reduction of feature classes, feature types, and attribution to simplify data; merge of network flow features at vertical relationship locations; conversion of artificial paths along coastline to coastline feature type; addition of M coordinates and values to network flow features; addition of Z coordinates, but not values, to all feature geometry; addition of value added attributes; switch to primary flow navigation by network features (NHDFlowline, route.drain) in place of reach features; and elimination of metadata boundaries. Process Date: 2004
See dataset specific metadata. Process Date:
GeoPlan downloaded this dataset from the Florida Department of Environmental Protection. The data was downloaded as a personal geodatabase and was in the following projection: Albers HPGN, Units: meters. The feature class NHDWATERBODY was converted to shapefile via ArcCatalog 9.2. Feature Type and Descriptions were joined to the shapefile based on the field FCODE. The join table was based of information gathered at: http://nhd.usgs.gov/NHDinGEO_FCodes_by_layer.pdf Additional details to be used in metadata were gathered from the following link: http://nhd.usgs.gov/NHD.pdf - All records were upcased. - Changed projection file to FGDL Albers - DESC_ field was added and calculated based on FCODE Descriptions - A DESCRIPT field was added based on Feature Type - A FGDLAQDATE field was added based on date GeoPlan downloaded the data Process Date: 20070815
Data imported to ArcSDE and exported as a shapefile. Process Date: 20090619
MAP PROJECTION PARAMETERS:

Projection                          ALBERS
Datum                               HPGN
Units                               METERS
Spheroid                            GRS1980
1st Standard Parallel               24  0  0.000
2nd Standard Parallel               31 30  0.000
Central Meridian                   -84 00  0.000
Latitude of Projection's Origin     24  0  0.000
False Easting (meters)              400000.00000
False Northing (meters)             0.00000

DATA SOURCE CONTACT (S):

Name:
Abbr. Name:
Address:


Phone:

Web site:
E-mail:
Contact Person:
         Phone:
        E-mail:
Florida Department of Environmental Protection
FDEP
3900 Commonwealth Boulevard M.S. 49
Tallahassee, FL
32399
(850) 245-8550

http://www.dep.state.fl.us/ GIS.Librarian@dep.state.fl.us

FGDL CONTACT:
Name:                   FLORIDA GEOGRAPHIC DATA LIBRARY
Abbr. Name:             FGDL
Address:                Florida Geographic Data Library
                        431 Architecture Building
                        PO Box 115706
                        Gainesville, FL  32611-5706
Web site:               http://www.fgdl.org

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