Batch Depression Contours (BatDep)
Type: Batch Application
Flags depression contours.
Batch Depression Contours is used to change the graphics pointer (i.e. line style) of depression contours.
Parameters for Batch Depression Contours
Workspaces to consider
Defines the workspaces to consider when running batch node.
Target Contour Layers
Defines the layers containing the contours lines to be flagged. A number line may be used to define the layers.
Depression Contour Graphics Pointer
Defines the graphics pointer to assign to depression contours. 10 is the default and produces tick marks that point downhill.
Depression Contour Maximum Area
Defines the maximum area that contours may contain in order to be considered for depression flagging. If this number is 0 then it will be ignored. This option is useful if all contours are being flagged (not just bottom contours).
A depression contour is...
Choose the definition of a depression contour that meets you needs. We have not been able to get our customer base to agree on definition of depression contour. Hence, the key processing parameter is a choice among the definitions. If you don't find a definition that meets you needs contact email@example.com to request a custom definition. Each of the definitions is described and presented with an example. The example data that will be used is shown below. In the left top is a straight forward pit and mound. In the bottom left is feature with elevation direction changes. On the right is settlement pond surrounded by a low berm. The surface inside the settlement pond alternates above and below the 100' contour.
Definition 1: A depression contour is "a closed contour that would hold water inside it"
This is the most straight forward definition, and the results are shown below. Notice:
Definition 2: A depression contour is "a closed contour inside a higher closed contour"
This definition makes any contour that is inside a higher closed contour a depression contour. Using this definition, the inside of a depression contour might not hold water. See the results below, note that
Definition 3: A depression contour is "any closed contour"
This definition is admittedly an abuse of the term 'depression contour', but it was requested. When used with graphic pointer (line style) 10 it marks closed contours with ticks that point downhill. See the example below, Note:
Definition 4: A depression contour is "the lowest closed contour that would hold water"
Using this definition contours on the way down are not marked; only the bottom contour is marked. See the example below. Note:
Definition 4: A depression contour is "the lowest contour(s) in a depression"
This is an alternative way to view contours at the bottom of a basin. All of the lowest contours are marked as depression contours. See example below. Note:
Definition 5: A depression contour is "the lowest empty closed contour that would hold water"
Using this definition a contour must not only hold water it must also be the lowest contour in a basin and contain no other contours (higher, lower, or equal elevation). See example below. Note: