GSDA:Formatting Spatial Data with ArcView GIS (3.x) for use in WMS

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Once spatial data are obtained, they often need to be formatted further before they can be used in WMS or GIS. Listed below are common formatting tasks used with WMS. Three common formatting scenarios are listed below:

  • Using ArcView GIS to convert data into a different coordinate system
  • Using ArcView GIS to clip out a watershed from spatial data
  • Using ArcView GIS join the hydrologic soil group attribute to an EPA soil type shapefile

How to Use ArcView GIS to Convert Data into a Different Coordinate System

  1. Start ArcView GIS. Click 'Cancel' to the 'Welcome to ArcView GIS' dialog if it comes up.
  2. From the File pull down menu, choose New Project.
  3. Make sure "Views" is selected in the project dialog box and click the New button. A new view titled "View1" will appear.
  4. Enlarge the "View1" window to a larger and convenient size, but make sure not to block out the project dialog box.
  5. Click on the "Add Theme" button GSDA AddThemeIcon.png.
  6. Browse to the drive and folder where the data shapefile (e.g., soil type or land use) is found.
  7. Select it and click OK. A new theme will appear on the left side of "View1". Turn the theme "on" by clicking a check mark into the small gray box next to it so that the data appears in the window (see Figure 1). If you move the mouse pointer over the data, you will notice the (x,y) coordinates at the top right corner of the ArcView screen. The coordinates will probably be in decimal degrees for latitude and longitude.
  8. From the File pull down menu, select Extensions...
  9. Scroll down the list and put a check mark next to "Projector!". If you do not find this as one of the possible extensions then you must copy this extension file (prjctr.avx) into ArcView's extension's directory. For a typical ArcView 3.x setup you should copy the prjctr.avx file found in the C:\ESRI\AV_gis30\ArcView\samples\ext to C:\ESRI\AV_gis30\ArcView\Ext32. Of course ArcView may be installed slightly differently on your system (D: rather than C:, or in a slightly different sub directory). You may need to search for the prjctr.avx file. Once the file is in the Ext32 directory it should appear in the scroll down list of extensions.
  10. Click OK.
  11. Since the data theme should already be the active theme, click the Projector tool button GSDA Projector.png near the top.
  12. Choose the appropriate output units (e.g., meters).
  13. Change the projection category and type as appropriate. For example, you might want to change the category to UTM 1983 and then change the type to Zone 12.
  14. You may choose "Yes" to recalculate area, perimeter, and length fields if you want to.
  15. Click "Yes" when asked to add the projected shapefile as a theme to the view.
  16. Make sure you select "View1" since this is the view you are using and click OK.
  17. Give the new shapefile a filename and tell ArcView where you want it saved to. Click OK.
  18. Once back in View1, uncheck the original theme and check the new theme that you just added.
  19. Make the new theme active by clicking once on its name next to the check mark.
  20. Click the Zoom to Theme button GSDA MoveToTheme.png at the top. Your new shapefile should now appear in View1, and as the mouse pointer moves over the data the coordinates displayed in the upper-right corner of the screen should now be consistent with the new coordinate system.
  21. The new shapefile is now converted to the correct coordinate system.
  22. If you want you may save your project in ArcView by choosing Save Project from the File pulldown menu, giving the project a filename and location to be saved to, and clicking Ok.


Figure 1.

How to Use ArcView GIS to Clip Out a Watershed from Spatial Data

  1. If you have correctly delineated a watershed in WMS, you should convert the watershed boundaries to a polygon.
  2. Export this polygon by choosing the Export command the the File pull down menu.
  3. Choose the Feature object polygons -> Shapefile option.
  4. Give your exported shapefile a name and choose where it will be saved to. Click OK.
  5. Start ArcView GIS. Click 'Cancel' to the 'Welcome to ArcView GIS' dialog if it comes up.
  6. From the File pull down menu, choose New Project.
  7. With Views selected in the project dialog box, choose the New button.
  8. A new view named "View1" should open up. Enlarge the "View1" window to a larger and convenient size, but make sure not to block out the project dialog box.
  9. Click the Add Theme button GSDA AddThemeIcon.png.
  10. Browse, locate, and select the watershed shapefile you exported from WMS and click OK.
  11. Make the theme visible by putting a check mark next to the theme name in View1. The watershed boundaries should appear (see Figure 1).
  12. Repeat the previous three steps again and load the data shapefile you are trying to clip (e.g., soil type or land use).
  13. Make the newly added theme visible as well by putting a check mark next to its name in View1 (see Figure 2).
  14. From the File pull down menu, choose the Extensions.. option.
  15. Scroll down through the list and put a check mark next to Geoprocessing and click OK.
  16. From the View pull down menu, choose GeoProcessing Wizard.
  17. Choose the Clip one theme based on another option and click Next.
  18. The input theme should be the data source shapefile (e.g., soil type or land use).
  19. The polygon overlay theme should be the watershed boundary shapefile you exported from WMS.
  20. Specify a filename and location for the output file to be saved.
  21. Click the Finish button.
  22. The new clipped theme will now be added to View1.
  23. Make the two original themes invisible by removing the check mark next to their theme names in View1.
  24. Make the new theme visible by checking the box next to its name.
  25. Make this theme is the active theme by clicking once on its name next to the check mark.
  26. Click the Zoom to Theme button GSDA MoveToTheme.png. Your watershed boundaries with the data's polygons that cross it should now be combined into one theme on the screen (see Figure 3).
  27. If you want, save your project in ArcView by choosing Save Project from the File pulldown menu, giving the project a filename and location to be saved to, and clicking Ok.

How to use ArcView GIS (3.x) to join the hydrologic soil group attribute to an EPA soil type shapefile

Since the EPA soil type shapefile 'statsgo.shp' does not contain the attribute for hydrologic soil group, it must be joined from the ArcView table file 'statsgoc.dbf'. This is necessary before WMS can compute a composite curve number (CCN) for a watershed.

  1. Start ArcView GIS. Click 'Cancel' to the 'Welcome to ArcView GIS' dialog if it comes up.
  2. From the File pull down menu, choose New Project.
  3. Make sure "Views" is selected in the project dialog box and click the New button. A new view titled "View1" will appear.
  4. Enlarge the "View1" window to a larger and convenient size, but make sure not to block out the project dialog box.
  5. Click on the "Add Theme" button GSDA AddThemeIcon.png.
  6. Browse to the drive and folder where the soil type shapefile is found. Select it and click OK.
  7. A new theme will appear on the left side of "View1". Turn the theme "on" by clicking a check mark into the small gray box next to it so that the soil type data appears in the window (see Figure 1).
  8. Click the Open Theme Table button GSDA OpenThemeTable.png at the top. The theme table for 'statsgo.shp' will appear.
  9. In the project dialog box, select Tables from the list.
  10. Click the Add button.
  11. Browse to the drive and folder where the table 'statsgoc.dbf' is found. Select it and click OK.
  12. With the 'statsgoc.dbf' table window active, click once on the field "Muid" found at the top so that it is highlighted.
  13. Click on the top bar of the "Attributes of Statsgo.shp" window to make it active. Also click once on the field "Muid" found at the top so it is highlighted.
  14. From the Table pull down menu, choose Join (see Figure 2). The window for 'statsgoc.dbf' will disappear.
  15. You've now successfully joined the hydrologic soil group attribute to your soil type shapefile.
  16. Make the "View1" window active by clicking somewhere on the top bar.
  17. With your projected and joined soil type theme still active, choose the Convert to Shapefile... command from the Theme pulldown menu. Give this new shapefile a name and save it to your disk.
  18. If you want, save your project in ArcView by choosing Save Project from the File pulldown menu. Give the project a filename and location to be saved to, and clicking Ok.