Problem

What do the user notifications "Conduit has adverse slope" or "Link slope is zero" mean?

Solution

The user notification "Conduit has adverse slope" means that the Invert (Start Node) is lower than the Invert (Stop Node) for the pipe. This may be as designed, and the storm and sewer products are able to compute systems where there are adverse slopes.

However, if this is not expected, you will want to review the conduits listed in the user notification dialog. Sometimes this is caused by drawing the pipe in the upstream direction, so the "start" node (the first one drawn) is actually at a lower elevation than the "stop" node (the second one drawn). Other times, it is caused by entering elevations incorrectly for the Inverts of the conduit or the structures at the endpoints. You can fix this by going to each affected conduit and examining it to see whether it has been drawn backwards or whether the node elevations are incorrect. If the elevations are correct, then the problem is just that the pipe is reversed. You can correct it by right-clicking the pipe and picking Reverse from the context menu, or from inside the Properties grid of the pipe by clicking the Node Reversal field (near the top of the grid) and then clicking the ellipsis button.

If the invert elevations for the start and stop nodes are identical, this will generate a user notification indicating that the slope is zero. If this not expected, you will need to look at the invert elevations for the pipe or for the end nodes to make sure the data is accurate. 

See Also

Is there a way to infer and assign invert elevations to nodes in my network?

How do I run the Element Property Inferencing tool with a negative or adverse slope?