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3D Hydrography Program 3DHP_all: Catchment

By NGP Standards and Specifications

Catchment is a polygon spatial table that represents the drainage divide.

catchment (spatial table)- Catchment is a polygon spatial table that represents the drainage divide bounded by inlet and outlet hydrolocations and surrounding a catchment area where water flows to a single flowpath and ultimately a common outlet. 

Name (Alias) Definition Type Allow Nulls Length Domain Default Values Comments
id3dhp Unique identifier for 3DHP features.  Text Yes 7 - -

This is a base-36 7-digit alphanumeric unique identifier that is not persistent.

This identifier links to the catchmentid3dhp and flowpathid3dhp attributes in

the derivatives table. Applied to catchment features in this case.
featuredate Date the feature was loaded into the 3DHP core database. Date Yes - - - -
mainstemid

A cross-dataset identifier for all flowlines that represent the

headwater to outlet path of a river.

 Text Yes 200 - -

A mainstem is equivalent to a feature with the same levelpathid in NHDPlus HR.

The text field will be a <geoconnex.us>*.
areasqkm

Area of feature in square kilometers based on regional spatial

reference systems.

 Double Yes - - -

Computed in projections based on specific locations, please see the Spatial Reference

System Section of this specification for more information
totestdrainareasqkm

Total estimated drainage area of all upstream catchments measured

in square kilometers based on regional spatial reference systems.

 Double Yes - - -

Computed in projections based on specific locations, please see the Spatial Reference

System Section of this specification for more information.

*More information about geoconnex can be found here: https://waterdata.usgs.gov/blog/nldi-geoconnex/.

Please note, the catchment spatial table in the 3DHP_all data service has not been populated in the 3DHP_all 2023.

Back to the 3D Hydrography Program 3DHP_all Specification