WMS:Drainage Tools

Contour Labels

The Contour Label tool manually places numerical contour elevation labels at points clicked on with the mouse. These labels remain on the screen until the contouring options are changed, until they are deleted using the Contour Label Options dialog, or until the Graphics Window is refreshed. Contour labels can also be deleted with this tool by holding down the SHIFT key while clicking on the labels. This tool can only be used when the TIN is in plan view.

Select Drainage Unit or Basin

The Select Drainage Unit or Basin tool is used to select basins which can then be either merged together or split. In addition to selecting basins, this tool can be used to select one of the basin icons.

Move Basin Labels

Computed drainage data may be displayed for each basin. However, when there are many basins, the screen can become cluttered with data. The Move Basin Labels tool allows basin data to be placed at a position other than the centroid, which is the default location. When moving a label, click in the desired basin and while holding down the mouse button, drag the cursor to the desired position on the screen and then release the button. An arrow will be drawn from the final position to the point first clicked in the basin.

Flow Path

The Flow Path tool allows the flow paths for specified points to be drawn. When this tool is active, clicking in the graphics window at a location on a TIN, or a DEM after TOPAZ data are computed will cause a flow path to be initiated from that point and followed "downstream" until a pit or local minima is reached, or until the path leaves the TIN/DEM. This tool can be very useful in checking portions of an edited TIN before stream and basin definition is completed.

The length and slope of overland and stream flow is displayed in the help window each time a new path is drawn. This can be helpful in obtaining parameters used to compute lag times with some empirical formulas. Stream distances are shown only after a stream has been created. In other words, channel flow is not counted in the stream distance unless a "stream" has been created along the channel.

Flow paths initiated from the centroid of each triangle or DEM cell can be displayed using the Draw Flow Patterns command in the TIN/DEM menu within the drainage module.

Other Drainage Tools

The remainder of the drainage tools are also found in the Terrain Data module tools, and the Map module tools.

Note: One difference is that the create feature point tool always creates an outlet point when used in the drainage module.