OK, so this article is a bit late.  I was reading the january edition of Professional Surveyor Magazine and came across an article about “Mapping Windmill Farms.”  The purpose of the article was to articulate the process to determine proposed locations of future windmills based on GIS data (municipalities, watersheds, soils, road acess, and proximity to residential areas).  As I read the article, I was amazed at what they were doing, but stymied why they weren’t using the software I’m pretty sure they already had.  What software is that you ask?

Anyone who has purchased Land Desktop or Civil 3D, you also own Map 3D.  OK, what is that?  That is Autodesk’s GIS application for creatng, editing and analyzing GIS data.  Let’s list a few things that can be done with Map 3D that would benefit the everyday tasks of land development:

  1. Reading Shapefiles (SHP), Digitial Orthophoto Quads (DOQ) and Digital Elevation Models (DEM).  These are the typical file format of many GIS data layers as noted in the article.  Map 3D can read these file types natively using FDO connections. (One thing about the GIS industry is all the acronyms they have 🙂 )   You don’t have to convert anything to DXF or strip away all the inherent data to get the linework. 

    01-fdo.png

  2. All these various pieces of data are in different coordinate systems, UTM NAD 83, State Plane NAD 27, etc and there is no way in AutoCAD to “georeference” all of this data.  Once you establish the coordinate system for the current drawing, all data referenced through the FDO connection, will trasform automatically. 
    02-coord-1.png03-coord-2.png
  3. DEM needs to be exported to DXF in order to create surface.  In fact, both Map 3D and Civil 3D can create surfaces out of DEM data.
    04-dem.png05-c3d-dem.png
  4. GIS data is flawed with bad data.  For the most part, you have to know what you’re playing with.  During the data creation stage of many of these data sources, they are digitized at a scale of 1:24000 or greater.  I don’t know about you, but my digitizing stunk and I was the best of the group.  Now magnify that inherent digitizing error over 1″=2000′.  Now you know why data when plotted at 100 scale is not accurate at all.  The way to know what kind of data accuracy you’re using is contained in something called metadata, or data about the data.  In this, you find who created the data, why they created it, what was their source, how was it created, how to contact them, etc.  So, is GIS data flawed?  No more so than using a Landscape Architects sketch as the final design.   Unless, of course, they did it in Impression.  🙂
    06-metadata.png

If nothing else, realize that that annoying task pane that most people close down in Land Desktop is actually the doorway into the Map GIS world.  If you’d like to know more, please contact me at my day job and I’d be glad to help you myself or point to someone in your area that can also help.

Hope this helps!