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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
PolyGeo
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Antarr Byrd
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  • 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 01 '14 at 01:04
  • @PolyGeo I've updated the question. Hope its what you were looking for. – Antarr Byrd May 01 '14 at 01:12
  • @PolyGeo When i click Zoom to layer in the TOC the data is visible but the rest of my map disappears. – Antarr Byrd May 01 '14 at 01:18
  • 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. – Michael Stimson May 01 '14 at 01:19
  • Did you contact the author (at the end of the linked page you supplied) and ask? It gives his email and phone number... – RyanKDalton May 01 '14 at 01:32
  • @MichaelMiles-Stimson The same problem persist without changing the coordinate system. When I zoom out I can see houston at a horrible scale on the bottom of my screen with the routes at the top of my screen on the same scale. – Antarr Byrd May 01 '14 at 01:35

1 Answers1

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

PROJCS["NAD_1983_StatePlane_Texas_South_Central_FIPS_4204_Feet",GEOGCS["GCS_North_American_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Lambert_Conformal_Conic"],PARAMETER["False_Easting",1968500.0],PARAMETER["False_Northing",13123333.33333333],PARAMETER["Central_Meridian",-99.0],PARAMETER["Standard_Parallel_1",28.38333333333333],PARAMETER["Standard_Parallel_2",30.28333333333334],PARAMETER["Latitude_Of_Origin",27.83333333333333],UNIT["Foot_US",0.3048006096012192]]

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.

PolyGeo
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  • Are you referring to the command line tool? – Antarr Byrd May 01 '14 at 01:40
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    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 http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Project/00170000007m000000/ – Michael Stimson May 01 '14 at 01:45
  • Its asking for a Geographic Transformation. Any idea which one I need? – Antarr Byrd May 01 '14 at 01:55
  • 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. – Michael Stimson May 01 '14 at 02:01
  • here is a post that might help or just confuse the issue http://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. – Michael Stimson May 01 '14 at 02:11
  • The houston data seems to be missing spatial data. When I add it to a new file it says missing spatial data so it can't project ;( – Antarr Byrd May 01 '14 at 02:12
  • @AntarrByrd I think you should ask a new Question for your last comment. I just downloaded the same data you did and it added to a Blank Map fine and, being the first layer in the Layers data frame, its Coordinate System was applied to that data frame as expected. At the moment your Question is confusing different things that make up an overall workflow. I recommend that you Accept the Answer on this one, which I can then tidy up to retrofit the Question to the Answer as an example of how to keep Questions here focussed on one issue at a time. – PolyGeo May 01 '14 at 02:44
  • @PolyGeo would it be helpful if i shared my project with you so you could see what I'm talking about? – Antarr Byrd May 01 '14 at 02:51
  • @AntarrByrd No, I think it is a common issue that you are encountering, and just needs to be worked through systematically to explain why you are not seeing what you expect. The Q&A format we use here is perfect for doing that, and learning from, as long as only one question is the focus of each Question. At the moment I am not seeing anything to suggest that the software is not working as it should. – PolyGeo May 01 '14 at 02:54
  • @PolyGeo I belive the problem may be with my other files which are a few years old – Antarr Byrd May 01 '14 at 02:57
  • @AntarrByrd That is always possible but not a conclusion that I would jump to when it is so easy to test by researching/asking it separate from this Question. – PolyGeo May 01 '14 at 02:59
  • @I'm not sure what question I would be asking that hasn't been asked here – Antarr Byrd May 01 '14 at 03:00
  • "How to check whether suspect shapefile is geolocated where it should be?" – PolyGeo May 01 '14 at 03:05
  • @PolyGeo Thanks for your time. http://gis.stackexchange.com/questions/94680/how-to-check-whether-suspect-shapefile-is-geolocated-where-it-should-be – Antarr Byrd May 01 '14 at 03:16