Embankment arc represent overland flow hydraulic structures. As they are usually smaller than the grid cells in width they are represented as a wall/weir combo along the grid cell edge. To create an embankment arc, trace out the feature arcs in WMS along the centerline of the actual embankment and then set the arc type to Embankment Arc. Embankment arcs often represent roads so a vertical curve calculator is available in the Embankment Arc Editor dialog where the elevation profile of the embankment can be adjusted. Finally, the lowest elevation points of the embankment arcs must be identified and the nearest vertex turned into a node with the low point feature turned on and the low point elevation set.