NHDLine

NHDLines represent linear NHD hydrographic landmark features used for cartographic representation.

 

See a complete list of Fcodes for hydrography features.

 

The attributes associated with NHDLine features are as follows:

Field Name

Definition

Comments

Permanent Identifier

Global ID and GUID data types store registry style strings consisting of 36 characters enclosed in curly brackets. These strings uniquely identify a feature or table row within a geodatabase and across geodatabases. This is how features are tracked in one-way and two-way geodatabase replication.

 

FDate

Date of last feature modification.

 

Resolution

Source resolution.  Currently NHD is available as separate resolutions.  Plans are to develop a single-resolution database holding the highest resolution data with tools to allow for generalization

Domain of values:

Local >1:12,000

High 1:24,000/12,000

Medium 1:100,000

GNIS_ID

Unique identifier assigned by GNIS, length 10.

GNIS_ID = “null” if no name associated with the feature

GNIS_Name

Proper name, specific term, or expression by which a particular geographic entity is known, length 65.

GNIS_Name = “null” if no name associated with the feature

LengthKM

Length of linear feature based on Albers Equal Area, length 8.

Computed

FType

Three-digit integer value; unique identifier of a feature type.

 

FCode

Five-digit integer value; composed of the feature type and combinations of characteristics and values.

 

Shape_Lenth

 Length in meters

All features should have a +integer value

Enabled

Created when Geometric Network is built

All features should be set to True (From the database).

New or modified features will have a Null value until network is rebuilt.