Combining overlapping meshes

hello everyone,
I have this topography composed of 9 meshes that i would like to clean up in order to have only one mesh or surface
Seems simple when you say it but i can’t find a way to do it on rhino
if anyone has a solution thank you in advance

Hello - here’s where I’d start - DupBorder and SplitMeshWithCurve with the results should get you the pieces you need - you can throw some away and Join others - ExtractPt on what you have left and MeshPatch the points.

-Pascal