What 3d software for underwater maps

[globalmark]

Hi

I want to draw some 3d underwater maps - covering Basic Topography , but also sometimes wrecks, sand and rock formations, if i can add fish would be great - I need a simple Program that I can draw (model, whatever it's called)
So need to show Surface bottom - underwater formations/reefs, wrecks, marine life , coral patches etc.

I want to print out and use where I work in diving.

Any advise or what program should I use would be great cheaper the better also. As I have only ever used 2d drawing maps before but want to try 3d.

thanks Mark

 

[mongrol]

Google Sketchup