Warren,
Thanks so much for the kind feedback. Helpful and much appreciated.
I was checking out DesignShare's 2007 new school design awards and found this school using curved green roofs which supports your comment about topography and viewing...and in this case, use.
In my blissful naivete I'm not so concerned about the drainage as the structural viability of the roof concept. I've played around some with analog models of triangulated irregular networks (TINs) and believe that a very light roof may be possible using a TIN framework overlaid/integrated with a layer of reinforced plastic foam. I have a project on the Open Architecture Network site that presents this concept in more detail. I think if the roof structural concept proved viable the drainage issues could be managed.
Following is an image of the layers I think would be necessary in a roof of this type. From the top down (vegetation, soil, rubber membrane, reinforced foam, interior membrane).
[image: House%202.0%20-%20Draft%205.jpg]
Thanks again,
Fred