The Errors layer is used to visualize suspected problems with the RAS Geometry. The Errors list is updated each time that a new feature is added to a layer. RAS Mapper will evaluate the feature for missing data or bad intersections with other layers and create a feature and description of the message in the attribute table. The user can force an analysis of possible errors by right-click on the Geometry and choosing the Validate Geometry menu item.
The error messages can be categorized as critical, warnings, and notes. Critical errors are problems that are significantly wrong, such as a cross section not having a River Name, Reach Name, or River Station, which could result from the cross section intersecting the river more than once or more than one river line. The result is a geometry that will not run in HEC-RAS. A warning informs the user something most likely is wrong (high confidence) with the model geometry, such as a bank line that crosses the river centerline, which may lead to model errors (the interpolation surface will not be correct, which affects mapping, but the model will run and most likely give good results). A note indicates there may be something wrong (low confidence) with the data, such as a cross section that doesn’t intersect with bank lines (RAS Mapper will automatically assign bank stations to the end points).
A geospatial feature (typically polyline) will be created for suspected problems and added to the Error layer. When the feature is added, information for the problem Layer that the feature originated from. The feature's name, and a description of the problem will be added to the attribute table. These features can be selected in the same manner as other features. The layer symbology can be changed and the features can be labeled. To get an idea of possible errors in the Geometry, turn on the Errors layer and hover the mouse over the error feature. A tool tip will display a stacked list of error messages based on the description in the attribute file (as shown below).
