An easy solution to set-up, but not very precise, would be to use a Clipping area
in combination with a Surface
, but this way the vertical part needs to be treated separately and it doesn't connect well. Attaching a modified scene showing this approach.
Another possible way would be to use the work-flow described in this thread
, but it requires to map UV coordinates carefully. Attaching a sample scene with a quick UV layout, which should be tweaked to equalize deformations better. Hope that helps a bit.