GIS for Water Resources
 

Flow Statistics

StreamStats Map
USGS: SteamStats Map
StreamStats is a Web-based tool that allows you to obtain streamflow statistics, drainage-basin characteristics, and other information for selected sites on streams. You can choose the site from an interactive map and obtain related information.

For example, if you select the location of a U.S. Geological Survey (USGS) data-collection station, you will get previously published information for that station from a database. If you select a location where no data is available (an ungaged site), GIS can estimate information for the site.

The GIS determines the boundary of the drainage basin above the site, measures the physical characteristics of the drainage basin, and solves the appropriate regression equations to estimate streamflow statistics for the site. The results are presented in a table and a map showing the basin outline.

Watershed Delineation

The suite of tools in Arc Hydro facilitates the delination of watersheds by using Digital Elevation Models (DEMs). DEMs consist of a sampled array of elevations for ground positions at regularly spaced intervals. GIS uses these DEMs to define the direction of the flow according to the topography and the drainage areas.

The DEMs may not always yield a good representation of the real world, and additional tools may be used to edit the DEM to improve the resulting delineations. With the tools in Arc Hydro, you can burn in streams or building walls at that effect. Another application developed for HEC aims at editing the DEM (HEC–GeoDozer).

Contact Us | Privacy | Legal | Site Map