Downloading Data From the NHD Viewer

Download a Prestaged Subregion

 

Introduction

 

The NHD Viewer can be used to locate and download prestaged Subregion data. Prestaged Subregions are prepackaged and have been extracted from the NHD database. Since the Subregions are prestaged all processing has already been done and there is no wait time to download the data. In this tutorial you will learn how to use the NHD Viewer to locate and download a prestaged Subregion.

 

This Tutorial is also available as a movie demo!  

   Download a Prestaged Subregion

 

           Already know which Subregion you need?

 

Step 1 Open the NHD Viewer

 

          Go to the NHD Homepage.

           

The navigation panel on the left hand side has a tab called  "Get NHD Data".  Hover your mouse over the tab and then select the option, "Go to the NHD Viewer".

          

The NHD Viewer will open in a new window.

 

             What is the NHD Viewer?

 

Step 2  Zoom to Subregion 1401

 

Zoom to Region 14 (displayed as HUC2-1401 in the viewer) by holding the shift key and drawing a box around HUC2-1401. Note: As you zoom in, more features will become visible. After zooming to the region, Subregion boundaries become visible.

 

         Subregion 1401 is now visible (displayed as HUC4-1401 in the viewer). Zoom in     

         further to Subregion 1401.

 

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Step 3 Set the Reference Area in the Download Data Tool

 

           Start by clicking on the Download Data button located at the top right of the

           viewer.

 

This will enable the "Download Data" tool and a "Download options" panel.

            

You can choose a reference area to download, such as "Index 24K", "Counties", "NHD Subregions", or you can click the link to download by current map extent. If you are zoomed out too far, a warning will instruct you to zoom in further. You may click the warning to automatically zoom to the correct scale.

 

Select the reference area called NHD Subregions. Notice that Subregion boundaries are now                            highlighted.

Step 4 Select Subregion 1401

 

Select Subregion 1401 by clicking on it on the map. The Subregion will be highlighted in green after it is selected. Information about the selection will come up under the selection tab in the pane on the left side of the viewer.

The window provides options to "Download Prestaged Personal Geodatabase" or "Download Prestaged File Geodatabase".

          

Step 5 Download Subregion 1401

Select the option to "Download Prestaged File Geodatabase". File geodatabases are preferred for NHD downloads because they typically have smaller file sizes than personal geodatabases. Some Subregions are too large to fit into a personal geodatabase and are only available as a file geodatabase.

 

           Not sure what the difference is?

          You will be prompted to open or save a zip file. Save the file to your local drive and extract the zip file.

           You are now ready to use the NHD Subregion in ArcMap!