Downloading. The NRCS. GIS data. Get Data button. the data for projection!

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1 Downloading GIS Data from the NRCS Geospatial Data Gateway and Bringing Thesee Layers into ArcMap The NRCS Geospatial Data Gateway provides access to spatial data for all of the U.S. While local governments typically have the best data available, this is a good place to initiate a data search! This document provides you with the steps necessary to find, acquire, and download GIS data. In addition, we ll show you how to get these data into ArcMap! 1. Access the Geodata Gateway here: and Click on the Get Data button 2. There are 5 steps that you will need to work through when downloading data from the Geodata Gateway. These steps include: a. Step 1 Where: What geographic location do you need? A single county, a selection of counties within a single state, or data for an entire state? Or a user definedd area (mult state ) Keep in mind that all of the data for your selected areas will be provided to you in the same projection! b. Step 2 What: What type of data do you need? Soils, jurisdictional boundaries, aerial photography, etc? c. Step 3 How: Why type of data format do you need? What iss your desiredd projection? How do you want thesee data provide to you (FTP, DVD, etc.) Using the NRCS Geospatial Data Gateway Page 1

2 d. Step 4 Who: Your contact information. Note that you need to provide a valid address! You will receive an notification that contains an ftp link e. Step 5 Review: Review your order, and you are done! You may receive an from the NRCS that contains an ftp link in a few minutes, hours, or days. The time period is contingentt on the size of your orderr and the number of orderr cued up in front of you! There s also a bonus step (Step 6)! We ll show you how to get your downloaded data into ArcMap! Step 1 Where Example: I am looking for some GIS data for Accomack County, Virginia. Obviously, if I was really serious about my data search, I d contact the local planner orr GIS coordinator first since the localities typically have the best data ( )! But, since I am in a hurry, I decided to jump right in and see what data the NRCS has archived andd made available to me (note that the NRCS does have other data assets that are not available to the public) First, I will establish my geographic area of interest (Accomack County, VA) Now, I am going to select the county that I am seeking data for. Remember, you can select more than 1 county at a time (but this is not always advisable ). Highlight the county names on this side, and send them to the other side! Using the NRCS Geospatial Data Gateway Page 2

3 Step 2 What Now select the GIS layers that you would like to download! Check out all of the aerial photography options! Your students can download a variety of aerial photography dates and examine changes in their communities over time (but also take note of how largee these data sets are ). What do you think accounts for the discrepancies in the sizes of the aerial photography options? (hint: you can find out additional informationn about each option, by clicking on the information icon. You can also access the metadata for each layer by expanding each layer (clicking the plus button, and then clicking on the m icon (see the 2005 National Ag. Imagery Program Mosaic option below). Some of the options will also let you preview the layer (the eye icon). When you have completed your selection, click <Continue>. Step 3 How Now you will need to specify your desired data format, projection option, and delivery method. Note that imagery (aerial photos, etc.) can only be provided in a native data format (usually MrSid, jpeg2000, etc.) and native projection (usually UTM). It just takes too much processing power (and space!) to convert these large datasets to different projections and formats! But don t worry, ArcGIS can read the provided formats and projections easily! Using the NRCS Geospatial Data Gateway Page 3

4 I do not see any reason (unless you are working on a really slow internet connection) to choose a delivery option other than FTP Download (besides, it is the only free option!). Step 4 Who You will need to complete this form. Be sure that your address is correct, otherwise, you will not receive the FTP link that is required to downloadd the data! Step 5 Review your order: You will be provided with a summary of information associated with your data! Make sure that everything is correct, and then DON T FORGET TO PRESS THEE PLACE ORDER BUTTON! You have now successfully identified and ordered some GIS data from the Geospatial Data Gateway! Now follow these steps to get your data into ArcGIS! Using the NRCS Geospatial Data Gateway Page 4

5 Step 6 (the bonus step ) Getting the data into ArcGIS It just takes a couple of steps to download the data and import it into ArcGIS! You will need to: a. Download the data b. Uncompress (extract) the data c. Add the layers into ArcMap! a. Download the data A few minutes after submitting my data order to the Geospatial Data Gateway, I received an with downloadd instructions. When you receive this , please be aware that if you have ordered several data layers, that there may be several FTP links that you will need to access. My Accomack data request, for example, has 2 ftp links. Here is a section from the Go ahead and download the data, and store these zip files locally. And be patient! Even with a highh speed Internet connection, the larger aerial photography filess can take minutes to download! Using the NRCS Geospatial Data Gateway Page 5

6 b. Uncompress (extract) the data The files that you have downloadedd have been compressed ( note the.zip extension). You will need to uncompress these files before ArcGIS will bee able to read them! To uncompress these files, simply highlight and right click on the file, and select the Extract All option. You will then be prompted to provide a location where the unzipped files will be stored. Click <OK> and voila! Your files have unzipped. Using the NRCS Geospatial Data Gateway Page 6

7 c. Add the layers into ArcMap! You can now open ArcMap and use the <Add Data> button! ArcMap! You are ready to startt working in Using the NRCS Geospatial Data Gateway Page 7