I have downloaded this zipped shapefile of bus routes from the City of Houston data portal.

I then performed these steps in ArcGIS Desktop 9.3.1:

  1. Extracted the shapefile from the *.zip
  2. Added this shapefile as a layer to a data frame which has data in a coordinate system of NAD_1983_UTM_Zone_15N and noticed that it did not draw where I expected it to
  3. Used ArcToolbox>Data Management Tools>Projections and Transformations>Define Project to change its coordinate system to NAD_1983_UTM_Zone_15N and observed that it still did not draw where I expected it to

Can you explain why this shapefile may not be drawing in the expected location?

As background the properties of a shapefile that is drawing in the expected location is:

Data Type:  Shapefile Feature Class 
Shapefile:  D:\Cloud Apps\Google Drive\...\tgr48201trt00.shp
Geometry Type:  Polygon

Projected Coordinate System:    NAD_1983_UTM_Zone_15N
Projection: Transverse_Mercator
False_Easting:  500000.00000000
False_Northing: 0.00000000
Central_Meridian:   -93.00000000
Scale_Factor:   0.99960000
Latitude_Of_Origin: 0.00000000
Linear Unit:    Meter

Geographic Coordinate System:   GCS_North_American_1983
Datum:  D_North_American_1983
Prime Meridian:     Greenwich
Angular Unit:   Degree
  • Would you be able to edit your Question to detail the precise steps you take from downloading the date, to where you expect to see the layer created from that data displayed on your map (but do not), please?
    – PolyGeo
    May 1, 2014 at 1:04
  • @PolyGeo I've updated the question. Hope its what you were looking for. May 1, 2014 at 1:12
  • @PolyGeo When i click Zoom to layer in the TOC the data is visible but the rest of my map disappears. May 1, 2014 at 1:18
  • Have a look at the extent and see if it's sensible, it's possible that it's in the wrong zone or geographical coordinates. It's possible that you've set it to the wrong coordinate system using define projection. May 1, 2014 at 1:19
  • Did you contact the author (at the end of the linked page you supplied) and ask? It gives his email and phone number... May 1, 2014 at 1:32

1 Answer 1


Your downloaded shapefile already had a coordinate system defined in its *.prj file:


You appear to have used Define Projection to change how the coordinate values (which are in feet) get interpreted (as meters). This does NOT project the coordinates.

I recommend that you try the Project tool instead.

  • Are you referring to the command line tool? May 1, 2014 at 1:40
  • 1
    It's in the toolbox, seeing as you are using 9.3 go to the index (i think it's that) and type in 'Project' to locate the tool. It will know (hopefully) the input coordinates then fill in the output coordinates and it will create an output with the geometries in the new coordinate system. Hint: try make it the same as the map. Here's a link to the tool in v10 but it should be very similar help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Project/… May 1, 2014 at 1:45
  • Its asking for a Geographic Transformation. Any idea which one I need? May 1, 2014 at 1:55
  • There should be a drop down list. I'm not familiar with U.S. datums and transformations to recommend one over the other. There should be an option like GRS_80_to_NAD83. The difference between methods might be trivial, perhaps someone in the U.S. could help here. Otherwise pick the first one, see how it lines up and then try the next one until you get the best result. May 1, 2014 at 2:01
  • here is a post that might help or just confuse the issue forums.arcgis.com/threads/97152-NAD83-to-GRS80 as I see it it's already in NAD83/lambert/feet but you just want to project feet to metres. Perhaps create your own ESRI projection based on NAD83/Lambert/US foot and define it as that using define projection. It is possible that the textural information isn't being interpreted properly. I have come across this situation before in data from MapInfo and that was how I resolved it. May 1, 2014 at 2:11

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