TUFLOW Message 2230
ERROR 2230 - Every vertice around merge region has been assigned a null (-99999.) elevation point.
A merge polygon (does not have Shape_Option of "NO MERGE") has null -99999 elevation assigned at every vertice around the polygon. The null (-99999) elevation point snapped to the polygon (region) tells TUFLOW not to merge into the surrounding zpts at that location. If all points are set to -99999, TUFLOW can't merge region.
Set the Shape_Option on the polygon to "NO MERGE", to prevent the polygon from merging with existing topography. If you want the polygon to merge, remove some of the null elevation points.
This can also occur if a polygon is using the "MERGE ALL" option whilst attempting to triangulate across an area where elevation data has not previously been defined. This occurs because TUFLOW's default elevation is initialized to a value of -99999. In this case, make sure that base topography data is defined in the area where the error is occurring. Note: 2d_zsh inputs are processed globally, even if outside the active code areas.