Water Resource Engineering Glossary

ArcView

Loading Extensions
All extensions (*.avx files) must be saved to the \AV_GIS30\ARCVIEW\EXT32 folder.

Import 71
IMPORT is a stand-alone program that converts an ARC/INFO interchange file (.e00) created on any other operating system into a data file. If you receive ARC/INFO data in interchange format you can use IMPORT 71 to convert it to a data source in a format that can be added to a project or view in ArcView.

Projector!
Projector is one of the free extensions which ships with ArcView. There are many such extensions which are not set up by default. These extensions are found in the samples/ext directory under Arcview. For one of these extensions to be available within the program, the files must be copied to the ext (UNIX) or ext32 (PC) directory under Arcview. For the Projector! extension to function correctly all files beginning with "prjctr" must be copied. The purpose of Projector is to convert a theme from one projection to another. The steps to do so and an example are presented below.

Steps to complete a change in projection:

Specify current system of units under view-properties-map units
Start Projector (new green buttom at top right of pull down menu; shows up after adding the extension)
Select the input projection parameters
Select output units
Select the output projection parameters
Select whether to recalculate area, perimeter and length fields using the new units
Determine whether to add the projected shapefiles to the current view
Select which view to add it to
Give the new theme a name

Map to World File Creator
This extenison will help the user create a world file for an image by picking control points between the image and a projected feature theme. This extension takes advantage of ArcView being able to do a first order affine fit of the image when a world file is available for the image. The first order fit can shift the image up or down and stretch the image in the vertical and/or horizontal direction. Now keep this in mind because it will not "warp" or "rubber sheet" the image. So if you have photos that were created with nadir and the principle point coninciding or very close to it then you should be able to get a reasonable fit. By that I mean the photos cannot be oblique which is caused by pitch and roll of the platform carring the image.

To use this extension place it in your ext32 directory and from the file->extensions menu check the Image to Map World File Creator.

You should see a Blue Diamond on the Project Button Bar.

Press this button to begin and you will be asked for the name of the image you want to create a World File for and the name of the Feature Theme you want to register it to.

On the left side of your tool bar you will see a new tool that looks like a flag. Choose this tool and with it pick Ground Control Points (GCP's) that have the same spatial location for both the image and the feature theme.

i.e. Pick a point on the image. . . Pick a point on the feature theme that is the same location.

This constitutes 1 GCP pair.

now continue

Pick a point on the image. . . Pick a point on the feature theme that is the same location.

..

..

..

Continue doing this until you have at least 6 GCP pairs.

For a first order fit you need minimum of 3 pairs but it is recommended by all that you have twice the minimum so I set it up in the code so that you had to pick 6 pairs.

Once your GCP's are chosen minimize the two view and open the table called Ground Control Point Table.

This table has 6 fields

field -> Use Pnts You will notice every record has this field ON

field-> Input x For the image x coordinate

field-> Input y For the image y coordinate

field-> Output x For the output x coordinate

field-> Output y Fort he output y cordinate

field-> rmsWill display the Root Mean Square for the image/feature for each record

You will notice a new button on the Table Button Bar. It is a capitol C. This button will calculate the fit and rms values for your control points. Press it and then look at the rms values in the RMS field.

Any one record that gives you a high rms value can be turned off by typing OFF in the Use Pnts field.

When the Use Pnts field is ON the coordinate will be use for calculating the coefficients for the fit and thus in the world file. When it is off that record will not be used.

Keep calculating the rms and turning records off until you are satisfied with the total rms. Just keep in mind that you have to have 6 GCP pairs ON for it to work.

Once you are done you should see a new button on the Button Bar that looks like a pencil and paper. This button will write the world file. Press it and you will be ask where to save the file. You should save it in the same directory as the image itself.

When done the project will close and then you can open up a new project and insert the image and feature them into a new view. Both of which should register.

GeoProcessing Wizard Extension

• Clip -- The clip option can be used to cut out a piece of one theme using the boundaries of another theme. For example, suppose you have two themes: one showing all of the roads in a state, and another of a county in that state. The clip option allows you to use the county theme, clip off the roads outside the county, and create a new view showing the county boundaries and the roads within the boundary.
  
• Dissolve -- Dissolving can be used to delete lines between adjacent polygons into a more simplified attribute. For example, consider a view showing areas in a county where different foods such as corn, wheat, barley, and milo are grown. The lines between these areas can be deleted or dissolved creating a new region renamed as "agricultural".
  
• Merge -- Merging allows the user to combine features in a theme. For example, if you have a theme containing soil property polygons, you can merge the polygons that have the same land use attribute.
  
• Intersect -- The intersect command allows you to integrate two spatial data sets. Only the features that lie within each of the theme boundaries are preserved.  For example, suppose you have two themes. One theme shows a map of the western states, and a second theme shows the Rocky Mountains. If these themes were intersected, a theme would be created showing a view of the areas where the Rocky Mountains intersect the western states.
  
• Union -- The union option can be used to create a new theme containing the features and attributes of two polygon themes. For example, suppose you have two themes; one theme shows where the soil liquefaction potential is high, and the other showing the areas with potentially large earthquakes. These views can be merged to determine hazard areas.
  
• Spatial Join -- The spatial join option takes two theme tables and joins them according to a specified field or a spatial attribute found in each theme. For example, if you have one theme that contains cities and their names, and another which contains the counties where the cities are located, a spatial join enables you to acquire the name of the county where the cities are located.

Spatial Analyst

ArcView Spatial Analyst introduces a broad range of powerful new spatial modeling and analysis features previously not available to desktop users. This new extension allows you to create, query, map, and analyze cell-based raster data and to perform integrated vector-raster analysis.

With Spatial Analyst you can:

• Convert feature themes (point, line, or polygon) to grid themes.
• Create raster buffers based on distance or proximity from feature or grid themes.
• Create density maps from themes containing point features.
• Create continuous surfaces from scattered point features.
• Create contour, slope, and aspect maps and hillshades of these surfaces.
• Do cell-based map analysis.
• Perform Boolean queries and algebraic calculations on multiple grid themes simultaneously.
• Perform neighborhood and zone analysis.
• Do grid classification and display, and more.

Unique to ArcView Spatial Analyst is the ability not only to work with raster-based data (including the ability to overlay, query, and display multiple raster themes) but also to do integrated raster-vector theme analysis such as aggregating properties of a raster theme based on an overlaid vector theme. For example, direct mail campaigns can be focused on customers within complex polygon areas that are determined by spatial analysis of drive time and proximity to service centers.

ArcView Spatial Analyst is particularly well suited for providing solutions to problems that require distance or other continuous surface modeling information to be considered as part of the analysis.  For example, site suitability analysis often requires combining information about slope (information best represented as raster data), as well as the location of roads and property boundaries (information best represented as vector data) to arrive at the best location for a new facility. Spatial Analyst can not only generate the appropriate surface representation of information from a variety of existing data sources, but it can also derive new information from the overlay of multiple theme types. The results are then used to suggest possible solutions to the original problem. http://www.esri.com/software/arcview/extensions/spatext.html

ARC/INFO

SHAPEARC
Writes shapefile spatial and attribute information to a ARC/INFO coverage.   Shapefiles store only one of the following feature types: line, point, multipoint or polygon.  Polygon geatures may overlap and are converted to regions.  Lines can optionally be converted as routes and sections.  Shape polygons are converted into regions because there is no way to insure that polygon shape features do not overlap.   If polygon topology is required the REGIONPOLY command can be used.

REGIONPOLY
Converts a regions subclass into a polygon coverages and creates an INFO table containing overlapping region information.

ARCSHAPE
Writes feature attributes or info records to a new shape data file.  The concept of shapefiles was adopted in ArcView version 2 to allow limited editing of theme information.  ARCSHAPE creates three files to store the geometry and DBASE attributes (.shp, .shx, .dbf).

GRID TO ASCII


ASCII TO GRID


GENERATE
Adds features to a coverage.  Coordinates for each feature may be entered from the terminal or from a file. Coordiantes read from an input file can be in x,y,z format, GENERATE ignores the z values if they exist.
GENERATE <cover>
If the coverage does not already exist GENERATE will create the coverage.  Note: GENERATE creates new coordinate features, it does not create topology or attributes for these features (use BUILD or CLEAN for this). 

PROJECTDEFINE
Interactive dialogue for entering the projection information for a data set.
Below are a couple of screen captures from the Arc/Info Help File.
   

WMS

Using Precipitation Data in a HEC-1 model
Using Precipitation Data in a WMS HEC-1 model In WMS, once the watershed delineated and the subasins are defined, a HEC-1 model can be developed. In WMS select the basin tool .  Double click on a drainage unit (also referred to as a subasin) and the Edit HEC-1 Parameters dialogue will pop. From this dialogue select the Precipitation button in the top left corner of the dialogue. The HEC-1 Precipitation dialogue will appear.

As seen above, there are four possible selections: No Precipitation, Basin Average, Gage and
Hypothetical storm. For the Basin Average method a rainfall distribution series must be defined. Such as a Type II 24 Hour. The Gage method requires at least three stations of available gage data from which a thiessen network is created. The Hyothetical storm allows the user to define the storm distribution or enter the storm frequency as a percent to be converted to an annual series rainfall.

Other
NRCS Landuse Classification Table
Classification Codes-first and second level categories

1   Urban or Built-Up Land
11 Residential
12 Commercial Services
13 Industrial
14 Transportation, Communications
15 Industrial and Commercial
16 Mixed Urban or Built-Up Land
17 Other Urban or Built-Up Land
2   Agricultural Land
21 Cropland and Pasture
22 Orchards, Groves, Vineyards, Nurseries
23 Confined Feeding Operations
24 Other Agricultural Land
3   Rangeland
31 Herbaceous Rangeland
32 Shrub and Brush Rangeland
33 Mixed Rangeland
4   Forest Land
41 Deciduous Forest Land
42 Evergreen Forest Land
43 Mixed Forest Land
5   Water
51 Streams and Canals
52 Lakes
53 Reservoirs
54 Bays and Estuaries
6   Wetland
61 Forested Wetlands
62 Nonforested Wetlands
7   Barren Land
71 Dry Salt Flats
72 Beaches
73 Sandy Areas Other than Beaches
74 Bare Exposed Rock
75 Strip Mines, Quarries, and Gravel Pits
76 Transitional Areas
77 Mixed Barren Land
8   Tundra
81 Shrub and Brush Tundra
82 Herbaceous Tundra
83 Bare Ground
84 Wet Tundra
85 Mixed Tundra
9   Perennial Snow and Ice
91 Perennial Snowfields
92 Glaciers

SDTS Conversion
Background

USGS 7.5-minute DEMs in SDTS format can be downloaded off the web from the USGS GeoData home page. These DEMs are extremely useful, but WMS cannot currently import them. Fortunately, a utility written by Solomon Katz at the BLM exists. This utility converts SDTS DEM files to Arc/Info ASCII grid format. The Arc/Info ASCII grid files can then be read into WMS. The steps for reading Arc/Info ASCII grid files into WMS are:
1.Download the sdts2arc.exe utility.
2.Uncompress your SDTS files and convert them to Arc/Info ASCII grid format
3.Import the Arc/Info ASCII grid(s) into WMS

• Download the sdts2arc.exe utility
  
  
• Uncompress your SDTS Files andConvert them to Arc/Info ASCIIGrid Format
  
  If you are using windows, this step is fairly easy if you have WinZip. After downloading the SDTS files to your hard drive, create a single directory on your hard drive for each of your SDTS files. HINT: Each directory you store your SDTS files in should have 8 or less characters in the SDTS file directory and all the higher level directories.  No spaces should be used for the directory names.
  
  For example, C:\My documents\SDTS\aspen\ should not be used. Instead, use: C:\data\SDTS\aspen
  
  Open each of your SDTS files in WinZip . For each of the SDTS files, change the "_tar" extension to ".tar". Then, extract the file to the correct SDTS sub-directory. Move the sdts2arc.exe DOS executable file to each of the SDTS sub-directories. Bring up a DOS prompt and go to the SDTS directory containing the SDTS files you wish to convert. Alternatively, double-click on the sdts2arc.exe executable in the directory containing the SDTS files you wish to convert. In either case, run sdts2arc.exe. When you download and extract an SDTS grid file, 18 files are extracted. One file is larger than all the rest, and has "ce" for the 5th and 6th characters. This file is the SDTS "CELL" file. When you run the sdts2arc.exe program, you will have to enter 3 items:
  
  1.The first 4 characters of your SDTS CELL file.
  2.The desired output file name. Typically, you will want to end your output file in ".grd". This file name extension is automatically added to the end of your output file name.
  3.The 7th and 8th characters of your SDTS CELL file.
  
  Here is what a successful run of the sdts2arc.exe program looks like:
  
  T:\geoscms\sdtsdems\taberne>sdts2arc
  
  Spatial Data Transfer Standard (SDTS)
  SDTS to ARCINFO ASCII GRID Utility
  SDTS2ARC BETA ver .004
  Use only SDTS Raster/DEM Files
  Another gis translation tool from
  Sol Katz(skatz@blm.gov), May 1998.
  
  Usage: sdts2arc (base_input_name)
  (base_output_file) (cell id)
  input file: 4 characters in position 1-4 of the base file name
  output file: output file without extension
  layer id: 2 characters in position 7 and 8 of base file name
  
  Enter 1st 4 characters of base SDTS file name
  (1234xxxx.DDF):
  1189
  
  Enter output file name (.GRD will be appended): taberne
  
  Enter the 2 characters in position 7 and 8 of the CELL file name, (xxxxCE78): l0
  
  Title: TABER NE, ID - 24000
  Data ID: LAT:: 43.375 LONG:: -112.5 SCALE:: 24000
  Map Date: 1994
  Data set creation date: 19980128
  
  cell width: 30.000000
  cell height: 30.000000
  rsnm: UTM
  zone: 12
  rows = 469, columns = 346
  Range: max= 5517, min= 4730, void= -32767,
  fill= -32766
  LAT/LONG of the 7.5 USGS Quad
  SW 368352.468750 4803526.000000
  NW 368623.281250 4817408.500000
  NE 378729.312500 4817218.500000
  SE 378479.343750 4803336.500000
  processing cells
  
  End of Program
  
  
• Import the Arc/Info ASCII Grid(s)into WMS
  
  Start WMS.
  Select the Import command from the File menu.
  Select the Arc/Info grid->DEM option and select OK. The Import Arc/Info grid dialog will appear.
  Select the Add button in this dialog, select one of the Arc/Info ASCII grid files written from the sdts2arc.exe program, and open it.  You can add several Arc/Info ASCII grid files in this manner. Select OK on the Import Arc/Info grid dialog after you are done adding all the files you wish. The Arc/Info ASCII grid files will be read into WMS.
  
  Final note--Some SDTS grids are in feet, some are in meters. You will need to figure out which grids are in feet and which are in meters. After you do this, you will need to read the grids with the same units into WMS, convert them to the units you are working in, export the DEM from WMS in Arc/Info ASCII grid format, and read all the files back into WMS in the same units.

Using EPA DEM data (using the spatial analyst extension in ArcView)

1. Go to http://www.epa.gov/OST/BASINS/gisdata.html and select the state and watershed of interest.
2. Download the DEM data and unzip it (it will look something like this: 16020203_dem.exe and extract to 16020203.shp)
3. Bring the shapefile into ArcView (at this point you could clip, with the use of the GeoProcessing extension, the specific area in the watershed in which your are interested).
4. Use the Projector! extension to project the data from geographic coordiantes (decimal degrees) to your coordinate system of choice.
5. After loading the Spatial Analyst extension in ArcView, go to the Theme drop-down menu and select "Convert to Grid."   ArcView will prompt you for a name and location of the file to be converted.   A conversion extent dialogue will pop up; select the name.shp (the name of the shapefile you are converting) for the Output Grid Extent combo box.  The default values for the other three lines are acceptable but can be edited.
6. In the conversion field dialogue choose the field you want for the cell values (i.e., do you want your data in meters or feet?)  Accept the prompt Join Feature Attributes to Grid and then you'll be given the option to add the theme to your current view.
7. Go to the File drop-down menu and select Export Data Source...(this also requires the Spatial Analyst extension).   Select the ASCII-Raster option and save the file (it will export as a *.asc file).
8. Open WMS and from the File drop down menu select the Import command -- Import it as an Arc/Info grid->DEM.

STATSGO data using Arc/Info

STATe Soil GeOgraphic (STATSGO) data are soil maps that the NRCS developed by generalizing the detailed soil survey data. The base mapping scale is the USGS 1:250,000 topological quadrangle. Each map unit in a STATSGO map is linked to the Soil Interpretations Record (SIR) data base. The SIR includes physical and chemical soil properties and interpretations for engineering uses. STATSGO data are available in continuous statewide coverages. The data can be obtained in Arc/Info 7.0 coverage, GRASS 4.13 vector, and USGS DLG-3 formats. Because of the large mapping scale and generalizations in the creation of STATSGO, it is not very useful for small urban watersheds.

The STATSGO database includes the HYDGRP field which contains the SCS hydrologic soil type. This field is useful for automated calculation of composite curve numbers in WMS. You must also have a land use coverage and a land use table to do this.

There are seven basic steps to get an Arc/Info STATSGO coverage into a usable format for WMS.

1. Obtaining the data.
2. Projecting the coverage into your watershed's coordinate system.
3. Preparing a coverage to clip out the region of your watershed.
4. Clipping the STATSGO coverage.
5. Joining your attribute table with the database containing the HYDGRP field.
6. Converting your coverage into an Arcview shapefile so it can be imported into WMS.
7. Importing your shapefile into WMS.

Following is a step by step proceedure for obtaining a STATSGO Arc/Info coverage and preparing it for use in WMS. For those who aren't familiar with Arc/Info, do all Arc/Info commands in the spatial workspace. (use &workspace /dirname/dirname/.../spatial).

1.Download the coverage for the state that your watershed is located in.

• Go to the STATSGO Data Access page.
• Select the Form-based Download (it is the easiest). You will then have to provide information to register with the NRCS.
• After you submit your information it will give you a link back to the previous page. This page also contains the information you will need to uncompress the data that you will be downloading.
• Scroll down and select either DOS/WINDOWS or UNIX, whichever operating system you are running on.
• This will take you to the ftp directory. Select the arc directory and then the data directory. Then select the state that your watershed is located in. For example, if my watershed was located in Utah I would select "ut.zip" or "ut.tar.Z" depending on my operating system.
• Follow the instructions on the Form-based download page to uncompress the data. The Arc/Info coverage will be located in Spatial directory and named after the state abbreviation. Both of the directories in the Spatial directory contain the files that make up the Arc/Info coverage (for those who are not familiar with the directory structure of Arc/Info coverages).

2.Project the coverage from Albers Conical Equal Area to the planimetric coordinate system that your other watershed data are in. Most of the time it will be either UTM coordinates or State Plane coordinates. But whatever coordinate system you are using, be consistant. You can find the projection arguments for the coordinate system you are using in the Arc/Info help (enter help at the Arc: prompt).

• Use the PROJECT command in ARC to project your coverage. Following is an example of projecting the Utah coverage into UTM coordinates (your state will likely have a different zone):

        Arc: project
        Usage: PROJECT <COVER | GRID | FILE> <input><output>
        Arc: project COVER ut ut1
        Project: OUTPUT
        Project: PROJECTION UTM
        Project: DATUM NAD27
        Project: UNITS METERS
        Project: ZONE 12
        Project: PARAMETERS
        Project: END
        Arc:

• Use the CLEAN command to build polygon topology for your projected coverage.

        Arc: clean
        Usage: CLEAN <in_cover> {out_cover}
        Arc: clean ut1

3. Preparing a coverage to clip out the region of the watershed.

• In the WMS map module, create a new coverage by selecting Coverages... from the Feature Objects menu and then selecting the New button in the Coverages dialog box.
• Change the Attribute Set of your new coverage to General and select OK.
• Use the create feature arc tool to create a polygon that completely encloses your watershed boundary. Select this arc and select Build Polygon from the Feature Objects menu.
• Select Export... from the File menu and then select the Feature object polygons -> Shapefile option.
• Name and save your shapefile (*.shp, *.shx, and *.dbf) in the Spatial directory.
• In Arc/Info, use the SHAPEARC command to convert this shapefile into an Arc/Info coverage. Then use the CLEAN command to build polygon topology. Following is an example of these commands.
  
  Arc: shapearc
  Usage: SHAPEARC <in_shape_file> <out_cover> {out_subclass}
  Arc: shapearc clipcov.shp clipcov
  Arc: clean clipcov

4.Clipping the STATSGO coverage.

• Use the CLIP command to clip your STATSGO coverage with the clip coverage that you created. Following is an example of clipping the Utah STATSGO coverage.
  
  Arc: clip
  Usage: CLIP <in_cover> <clip_cover> <out_cover>{POLY | LINE | POINT | NET | LINK | RAW}
  Arc: clip ut1 clipcov soilcov POLY

5. Now you need to join your clipped soils coverage attribute table with the database file that contains the HYDGRP field. This database file is named "comp".

• Use the JOINITEM command to join your coverage's polygon attribute table (*.pat) with the "comp" database file. Use the MUID field as the relate item and the start item. Following is an example of this command.
  
  Arc: joinitem
  Usage: JOINITEM <in_info_file> <join_info_file><out_info_file> <relate_item> <start_item>
  Arc: joinitem soilcov.pat comp soilcov.pat MUID MUID

6. Converting your coverage into an Arcview shapefile so that it can be imported into WMS.

• Use the ARCSHAPE command to convert your soils coverage into an Arcview shapefile. Following is an example of this command.

       Arc: arcshape
       Usage: ARCSHAPE <in_cover> <in_feature_class><out_shape_file>
       Arc: arcshape soilcov POLYS soilcov.shp

• You are now ready to import your soil coverage into WMS.
  

7. Importing the shapefile into WMS.

• Create a new coverage in the map module by selecting Coverages... from the Feature Objects menu and then selecting the New button in the Coverages dialog box.
• Change the Attribute set to Soil Type.
• Change the name of the coverage to indicate that it is a soil type coverage and select OK.
• Select Import... from the File menu.
• Select the Shape file -> Feature objects option and select OK.
• Under Polygons select the button.
• Find and open the soils shapefile that you created.
• You will notice in the window to the right of Polygons that some text appears. This window shows which fields in your shapefile are mapped to WMS fields. Since the shapefile contained the field HYDGRP, WMS automatically mapped it to the SCS soil type. If your hydrologic soil type field was named something else you could manually map it to the SCS soil type by selecting the Attribute mapping button.
• Select OK to finish importing your shapefile.

You now have a soils coverage that you can use to calculate composite curve numbers. Of course, you must also have a land use coverage and a land use table to do this.

Soils
Using EPA data (without the spatial analyst ArcView extension)

1. Go to http://edcwww.cr.usgs.gov/doc/edchome/ndcdb/ndcdb.html and obtain either a 7.5 or 1:250,000 DEM quad.  Note: The resolution for a 7.5 min quad is much better than the 1:250,000, i.e., a 7.5 min DEM has data every 30 meters while a 1:250,000 has data every 90 meters.
2. For the 7.5 min quads follow the intructions on the tools/utilities page to convert this data into grid (thus readable for WMS) format.
3. Import the DEM into WMS.
4. Using the Create Feature Arc tool in the WMS Map module to create a polygon that completely encloses your watershed boundary. Select this arc and select Build Polygon from the Feature
   Objects menu. Select Export... from the File menu and then select the Feature object polygons -> Shapefile option.
5. Add this shapefile into a view in ArcView.
6. Go to http://www.epa.gov/OST/BASINS/gisdata.html to obtain soil type and landuse data for the general region where the DEM data is located.
7. Add these shapefiles to the current view and, using the GeoProcessing Wizard, clip out the soil type and landuse data corresponding to the DEM data.  See "Clip" instructions here.
8. Join corresponding MUID fields in ArcView.
   • Add the Statsgo.shp file in a View window.
   • Go to the project dialogue and single click the Tables icon then click on Add in the top right of that same dialogue.
   • Select the Statsgoc.dbf file.
   • Select the MUID field in both the Statsgo.dbf and Statsgoc.dbf files.  Make sure the Statsgo.dbf file is the active table.
   • In the Table drop-down menu select Join (all of the fields will be visually added to the Statsgo.dbf file).
   • Creat a new "dummy" field.
     • From the Table drop-down menu select Start Editing.
     • From the Edit drop-down menu select Add Field... give it a name and select Type String.
   • Select the "dummy" field and then select the Calculate icon (note: this macro will not be activated unless you are still in Edit mode).
   • Double-click the Hygrp field (i.e., the default will say dummy = )
   • In the Table drop-down menu select Remove All Joins
   • Create a new field called Hydgrp and copy the contents of "dummy" into Hydgrp using the calculator macro (see above).  Note:  If you don't add another field and copy the information in as described above (i.e., you make an alias to the "dummy" field) the dummy field will have to be mapped manually in WMS to the SCS soil type.

Soils
The EPA Basins soils data is also in shapefile format.  This works very well in WMS since the soil data must be in shapefile format to bring in as a soil coverage.