The South Carolina Department of Natural Resources (SCDNR) began developing a statewide geographic information system (GIS) natural resources database in 1989. Originally, this database was to serve a specific project, the Edisto River Basin Project, but has grown to encompass most of the state. The 7.5 minute, 1:24,000 U.S. Geological Survey (USGS) topographic maps were used as the base, providing a standard scale from which to map the state's natural resources. This scale permits large-scale analyses to be performed that previously had been impossible. This data is being made available free of charge to the public in an effort to facilitate natural resource decision making, analyses, and education in South Carolina.
The data layers being developed as part of this effort are: soils, wetlands/landuse, digital line graphs, digital elevation models, digital raster graphics (scanned topographic quadrangle maps), and color infrared digital orthophoto quadrangles (DOQs). The digital raster graphics files for South Carolina are provided by the South Carolina Department of Commerce.
The SCDNR On-Line Data Clearinghouse is located at http://www.dnr.state.sc.us/etc/data.html.
Click SCDNR GIS Data Clearinghouse.
The GIS Data Info page provides background information about the various data layers.
The Data Status Maps show the completion of the various data layers, by 7.5 degree quad. It is a good idea to use this section before attempting to download the data.
The Download Data page is where the actual GIS layers are located. The first time you access the database you will be asked to register. After registering, you will receive a reference identification number, which combined with your first name, will be used as your password to access the system in the future.
Once you have logged onto the system, you will see the SCDNR clearinghouse main menu.
There are three ways to get to the data layers from this menu. The first, County Map Query is a graphical means for selecting the county and the 7.5 degree quad you are interested in. The second, County Text Query provides a list of all the counties in South Carolina. After you select the county of interest, you are provided with another list to select the quad you are interested in. Finally, if you already know the name of the quad, you can click on the Quadrangle Text Query to select the quad from a list.
After selecting the 7.5 degree quad you are interested in, a Data Availability Page will appear.
If a layer is complete, the name of the file will appear in blue in the data file name column.
Note: There are a few .grd (GRID) files that can be downloaded from the SCDNR web page. These files as USGS Digital Evlevation Models (DEM). To view these data in ArcView®, you need the add-on Spatial Analyst® extension. To view the data, click File, Import Data Source, select USGS DEM from the pull down menu, click OK, and provide a file name for the new file.
To download the data, click on the file name. After a few seconds (depending on the speed of your modem) the page will load on to the screen. It might appear as symbols. Don't panic, that is the way that it is supposed to look. See the example below.
If you are using Netscape® as your browser, wait until the page has finished loading and click File then Save As. Select the directory/folder that you want the data saved in and click Save.
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The procedure is slightly different if Internet Explorer® is your browser. After the page has finished loading, click File then Save As. In the Save as type box select Text File (*.txt). Select the directory/folder that you want the data saved in and click Save. After you have saved the file, go to Windows Explorer or your File Manager and check to see if the file has a .txt extension. If you see the .txt extension, right mouse click on the file, select rename, and remove the .txt extension from the file. |
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Depending on the size of the data set and the speed of your modem, the download will take anywhere from a few minutes to an hour. Be sure to check the size of the file (beside the file name) before you download.
The majority of the files are in an ARC/INFO® Export format with the .e00 extension. Before you can view the data in ArcView, you must first use the import71 tool in ArcView.
Coverages are often transported as export (.e00) files. These .e00 files (created in ARC/INFO) contain all of the necessary geospatial information and they are a safe way to transfer data. Once created, the .e00 file can be transferred to another location where it can be imported into ArcView using the following steps.
If you have ArcView loaded on your computer, navigate to the following directory on your computer.
In Bin32, there should be a file called import71.exe. Double click on that. If you are going to be doing a lot of importing, it would be wise to drag the import71 shortcut on to the desktop environment.
A box called Import71 Utility will pop up. Use the browse option to select the file you want to import. In the Output Data Source, type only the name you want the imported file called. Do not include the name of the drive or an extension. The program will place the newly imported file in the same directory as the original file.
If you get an error message saying that your file cannot be accessed, check to make sure that you did not download data onto a network drive. Before you import, you will have to copy the file to your local hard drive.
After the import is complete you may view the data layers in ArcView. If you are in need of further instruction, look at the IMPORT help page in ArcView.