How can I achieve this please?

 From:  Sutts (SUTTS99)
9967.1 
Hi,

I have a model of a road system (flat) in MOI that I'd like to convert into a 3D model by projecting it onto a rolling landscape surface. i.e. the roads gain the missing element of height.

I have all the height data for my landscape, sampled in a 1m grid. Wondering how I can load this landscape height data into MOI please?
Is there a script I can use to construct a mesh based on coordinates and height data?

Thanks!