Thanks pat,
I also have a lot of grid tools in python (btw very similar to yours, going to/from postgis databases, shape, gmesh, fvcom formats etc) but was hoping that dwater spatial plots had already been coded, given that dwater seems to be readily used from telemac.
The lack of response suggests that this extension isnt used as often as I thought.
Further investigation suggests the easiest way is to fill a telemac grid result file using the dwater dido aggregation file that provides the mapping from the telemac grid to dwater grid. This is relatively easy.
The 3d or 2d plotting can then be readily done using matplotlib. Or once a serafin file has been created use paraview (with the new serafin reader plugin I recently posted).
Cheers