Streamstats

StreamStats uses digital map data and a Geographic Information System (GIS) models (e.g.ArcHydro) in the background to automatically determine the basin characteristics for ungaged sites that are used in the regression equations to estimate the flood discharges. The user needs to select the watershed outlet point on the defined stream.
The basin characteristics report generated provides the information on the following parameters:

• Drainage area; square miles
• Percent of area covered by water and wetland
• Mean population density, people per square mile
• Slope along the flow path between points 10% and 85% of thelength along the longest flow path determined in GIS; ft/mile
• Total stream length; miles
• % Area covered by forest
• % Area covered by urban land use
• % Area covered by wetlands
• Average basin elevation; ft

These parameters are used in the regression equation to estimate the flows for varying frequency storm events. The flood discharge is provided for the 2,5,10, 25,50,100, and 500 year storm events.