This the second Water Geomorph that I'm working on for the +GeomorphMapContest. The original pencil sketch can be found here.
For this one I actually drew the bridge on a separate sheet, scanned it, and placed it on the main outline. Next I'll print the combined drawing 6up on a sheet and sketch details multiple times. Then I'll scan the best versions of the new elements, clean them up, and drop them in one-by-one.