Elevation-Derived Hydrography READ Rules: Sink
A Sink/Rise is the place at which a stream disappears into an under- ground conduit or reappears at the surface from an underground conduit, or an isolated depression where the network ends.
Attribute/Attribute Value
Each feature requires domain codes to be entered into the attribute table for the feature class (Elevation-Derived Hydrography Feature type description, associated geometry, and use classification table in the Elevation-Derived Hydrography Data Acquisition Specifications 2023 revision A2). See “Field Definitions and Domain Values for Attributes” section for more information on Elevation-Derived Hydrography code definitions.
Delineation
The limit of sink is the place at which a stream disappears underground or reappears at the surface.
Representation Rules
When delineating a feature, it must be created with the appropriate geometry, either point, line, or polygon, which is determined by the size of the feature or the length along different axes of the feature (table 15).
Special conditions: none.
Table 15. Sink/Rise Representation Rules.
| Kind of feature object | Area | Shortest Axis | Longest Axis |
| 0-dimensional (point) | greater than 0 | -- | -- |
| 1-dimensional (line) | -- | -- | -- |
| 2-dimensional (polygon) | -- | -- | -- |
Data Extraction
Capture Conditions
If stream disappears,
then capture at the point of disappearance.
Attribute Information
FClass 1—Hydrography feature defined within the collection criteria of the elevation-derived hydrography specifications.
FCode 45000—Sink (the place at which a stream disappears into an under- ground conduit or reappears at the surface from an underground conduit, or an isolated depression where the network ends).
EClass 0—Not used for elevation derivative.
Source Interpretation Guidelines
A sink feature should be used at the lowest point of elevation in a playa feature.
