3D Hydrography Program 3DHP_all: DrainageArea

Drainagearea is a polygon spatial table that is an aggregation of catchments.

drainagearea (spatial table)- Drainagearea is a polygon spatial table that is an aggregation of catchments.

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. Applied to drainagearea features in this case.
featuredate	Date the feature was loaded into the 3DHP core database.	DateTime	Yes	-	-	-	-
huequivalent	Hydrologic unit code per Watershed Boundary Dataset (WBD) coding system.	Text	Yes	200	-	-	This is a <geoconnex.us>*. This attribute will not be populated initially.
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.

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

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