Obtaining Hydrologic Data through the Internet


Digital Elevation Models (DEMs)

Three Arc Second DEMs of the United States

What are 3" Digital Elevation Models?

Quick Connect to 3" DEM Web Site

Fifteen Arc Second DEMs of the United States

What are 15" Digital Elevation Models?

Quick Connect to 15" DEM Web Site

Thirty Arc Second DEM of the World (GTOPO30)

What are 30" Digital Elevation Models?

How to download a 30" DEM

Quick Connect to 30" DEM Web Site


Digital Line Graphs (DLGs)

1:2,000,000 DLGs

What are 1:2,000,000 Digital Line Graphs?

Quick Connect to DLG Web Site

1:100,000 DLGs

What are 1:100,000 Digital Line Graphs?

Quick Connect to DLG Web Site


Hydrologic Unit Codes (HUCs)

What are Hydrologic Unit Codes?

Quick Connect to HUCs Web Site


Land Use/Land Cover Files (LULC)

What are Land Use/Land Cover Files?

Quick Connect to EPA LULC Web Site

A process for obtaining the LULC files from the EPA

Quick Connect to USGS LULC Web Site


River Reach Files (RF1)

What are River Reach Files?

Quick Connect to RF1 Web Site



Other Useful Internet Sites for Water Resources and GIS
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