StreamStats in Georgia: Streamflow Statistics for Any Point on a Stream

The statewide Georgia StreamStats interface. USGS.

What it is

The USGS provides streamflow information to help people understand the nation's water. Water managers, engineers and scientists use streamflow statistics to protect people and property in floods and droughts and to manage water resources.

StreamStats is a web GIS application, built by the USGS with the Environmental Systems Research Institute (Esri), that gives streamflow statistics, basin characteristics and descriptive information for USGS streamgages and for any point a user picks on a stream, gaged or not. It is rolled out state by state so data can be tailored to each state. The USGS built Georgia's version with the Georgia Environmental Protection Division and the Georgia Department of Transportation; it's reached through the national portal at streamstats.usgs.gov.

What it can do (2014)

• Navigate base maps — roads, streams, political boundaries, USGS topographic maps — and zoom by drawn box, coordinates, place name, stream reach code or scale.
• Look up published peak-flow frequencies and other statistics for USGS streamgages, with links to historical and real-time data in the National Water Information System.
• Delineate (and edit) the drainage basin above any point on a stream.
• Compute basin characteristics — drainage area, stream slope, mean annual rainfall, land cover from the 2006 National Land Cover Dataset — for that point.
• Estimate rural and urban peak flows, with indicators of their accuracy.
• Download shapefiles of the outlet point, basin, longest flow path and slope points.
• Trace the connected stream network upstream or downstream, and the path water takes from any point on land to and down the stream.
• Plot elevation profiles and save the coordinates to Excel.
• Print maps and reports.

Several functions are also available as web services for other websites and desktop GIS.

A drainage basin delineated in Georgia StreamStats. USGS.

The numbers

• Published statistics are available for over 700 USGS streamgages in Georgia, with notes on any regulation of flow and the gage type (continuous or partial record).
• 18 basin characteristics are computed for any chosen point.
• Statistics at ungaged points come from published USGS regional regression equations — users should understand their limits and accuracy.

A basin characteristics report for a point on a stream. USGS.

Why it matters

Basin delineation, basin characteristics and flow statistics were once time-consuming and often not reproducible. StreamStats makes them fast and consistent, combining the state's local data with national datasets in a framework that can be updated — useful for bridge and road design, water quality and quantity management, basin studies, and the effects of urbanization on streamflow.

Sources

Based on Anthony J. Gotvald and Jonathan W. Musser, "StreamStats in Georgia: A Water-Resources Web Application," U.S. Geological Survey fact sheet, prepared with the Georgia Environmental Protection Division and the Georgia Department of Transportation; a work of the United States government in the public domain. The screen captures are taken from the fact sheet's PDF.