I work on a MODFLOW Model using GMS to simulate subsurface water exchanges between a small straightened stream and its heavily modified alluvial plain.

I’m looking for efficient methods to modify my 3D Grid to simulate active restoration measures, such as backfill removal and remeandering of a straightened channel (which imply to carve my 3dGrid). Those simulations involved to null certain cells (threw IBOUND parameter) but also I would like to modify the surface morphology of my grid (to simulate a new meandering channel for example).

To do so, from what I understand, I would need to export my 3D grid to a solid, modify that solid surficial morphology (with a new TIN maybe) and then recreate a 3Dgrid. Is that even possible?

Thank you in advance for your advice.

I wish a beautiful day!